Efficacy, Benefits, and Harms of a Self-management App in a Swedish Trauma-Exposed Community Sample (PTSD Coach): Randomized Controlled Trial

Background Self-guided interventions may complement and overcome obstacles to in-person treatment options. The efficacy of app interventions targeting posttraumatic stress disorder (PTSD) is unclear, and results from previous studies on PTSD Coach—an app for managing trauma-related distress—are inconsistent. Objective This study investigates whether access to the Swedish version of the PTSD Coach affects posttraumatic stress, depressive, and somatic symptoms. In addition, we aim to assess the perceived helpfulness, satisfaction, negative effects, response, and remission related to PTSD Coach. Methods Adults who had experienced potentially traumatic events in the past 2 years were randomized (1:1) to have access to PTSD Coach (n=89) or be on the waitlist (n=90). We assessed clinical characteristics at baseline (semistructured interviews and self-rating scales) and after 3 months (self-rating scales). We analyzed the data in R software using linear mixed effects models, chi-square tests, and Fisher exact test. Results Intention-to-treat analyses indicated that access to PTSD Coach decreased posttraumatic stress and depressive symptoms but not somatic symptoms. More participants who had access to PTSD Coach responded with clinically significant improvement and fewer instances of probable PTSD after 3 months compared with waitlist controls. Overall, participants found that PTSD Coach was slightly to moderately helpful and moderately satisfactory. Half of the intervention group (36/71, 51%) reported at least one negative reaction related to using PTSD Coach (eg, disappointment with the app or its results, arousal of stress, or distressing memories). Conclusions Using PTSD Coach may trigger symptoms among a few users; however, most of them perceived PTSD Coach as helpful and satisfactory. This study showed that having access to PTSD Coach helped improve psychological trauma-related symptoms. In addition, we have discussed implications for future research and clinical practice. Trial Registration ClinicalTrials.gov NCT04094922; https://clinicaltrials.gov/ct2/show/NCT04094922

yes: all primary outcomes were significantly better in intervention group vs control partly: SOME primary outcomes were significantly better in intervention group vs control no statistically significant difference between control and intervention potentially harmful: control was significantly better than intervention in one or more outcomes inconclusive: more research is needed Övrigt: Approx. Percentage of Users (starters) still using the app as recommended after 3 months * Overall, was the app/intervention effective? * Identify the mode of delivery. Preferably use "web-based" and/or "mobile" and/or "electronic game" in the title. Avoid ambiguous terms like "online", "virtual", "interactive". Use "Internet-based" only if Intervention includes non-web-based Internet components (e.g. email), use "computer-based" or "electronic" only if offline products are used. Use "virtual" only in the context of "virtual reality" (3-D worlds). Use "online" only in the context of "online support groups". Complement or substitute product names with broader terms for the class of products (such as "mobile" or "smart phone" instead of "iphone"), especially if the application runs on different platforms.

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Does your paper address subitem 1a-i? * Copy and paste relevant sections from manuscript title (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "...a Self-Management App (PTSD Coach)...". The app refers to a mobile app or smartphone app.

1a-ii) Non-web-based components or important co-interventions in title
Mention non-web-based components or important co-interventions in title, if any (e.g., "with telephone support"). Does your paper address subitem 1a-ii?
Copy and paste relevant sections from manuscript title (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study No additional clinical support was administered. "Seven days after randomization, we called all participants and offered the opportunity to ask questions regarding the study or technical support" (from the main manuscript).

1a-iii) Primary condition or target group in the title
Mention primary condition or target group in the title, if any (e.g., "for children with Type I Diabetes") Example: A Web-based and Mobile Intervention with Telephone Support for Children with Type I Diabetes: Randomized Controlled Trial

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Does your paper address subitem 1a-iii? * Copy and paste relevant sections from manuscript title (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "... in a Swedish, Trauma-Exposed Community Sample" Mention key features/functionalities/components of the intervention and comparator in the abstract. If possible, also mention theories and principles used for designing the site. Keep in mind the needs of systematic reviewers and indexers by including important synonyms. (Note: Only report in the abstract what the main paper is reporting. If this information is missing from the main body of text, consider adding it)

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Does your paper address subitem 1b-i? * Copy and paste relevant sections from the manuscript abstract (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study Background: PTSD Coach is "[s]elf-guided", "an app for managing trauma-related distress". Methods: We compare "access to PTSD Coach" to "waitlist". Specific app components (psychoeducation, symptom self-assessment, distress management exercises and contact info to professional and crisis resources) are not described in the abstract but elaborated in the main body of text.

1b-ii) Level of human involvement in the METHODS section of the ABSTRACT
Clarify the level of human involvement in the abstract, e.g., use phrases like "fully automated" vs. "therapist/nurse/care provider/physician-assisted" (mention number and expertise of providers involved, if any). (Note: Only report in the abstract what the main paper is reporting. If this information is missing from the main body of text, consider adding it) Rensa markering subitem not at all important 1 2 3 4 5 essential Does your paper address subitem 1b-ii?
Copy and paste relevant sections from the manuscript abstract (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study Access to PTSD Coach was provided without clinical assistance or human involvement. After a week "we called all participants and offered the opportunity to ask questions regarding the study or technical support" (from the main body of text).
1b-iii) Open vs. closed, web-based (self-assessment) vs. face-to-face assessments in the METHODS section of the ABSTRACT Mention how participants were recruited (online vs. offline), e.g., from an open access website or from a clinic or a closed online user group (closed usergroup trial), and clarify if this was a purely web-based trial, or there were face-to-face components (as part of the intervention or for assessment). Clearly say if outcomes were self-assessed through questionnaires (as common in web-based trials
Copy and paste relevant sections from the manuscript abstract (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study Participants were recruited online via social media for the unblinded, web-based trial. Participants who enrolled were assessed for inclusion and exclusion criteria. "We assessed clinical characteristics at baseline (semi-structured interview and self-rating scales) and 3 months later (self-rating scales)." Interviews were conducted remotely over the phone.
Copy and paste relevant sections from the manuscript abstract (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study Number of participants in each group is reported under the methods section of the abstract, "...randomized (1:1) to access to PTSD Coach (n=89) or waitlist (n=90)." We did not register objective attrition or adherence metrics nor user data for the trial version of the app due to privacy concerns. "Intention-to-treat analyses..." of 179 participants "...indicate that access to PTSD Coach decreased posttraumatic stress and depressive symptoms, but not somatic symptoms." In the main body of text, we clarify that "[a]t follow-up, 17 App access participants stated that they had not used PTSD Coach" and "four waitlist participants reported having used PTSD Coach (presumably the English-language version of the app)."

1b-v) CONCLUSIONS/DISCUSSION in abstract for negative trials
Conclusions/Discussions in abstract for negative trials: Discuss the primary outcome -if the trial is negative (primary outcome not changed), and the intervention was not used, discuss whether negative results are attributable to lack of uptake and discuss reasons. Does your paper address subitem 1b-v?
Copy and paste relevant sections from the manuscript abstract (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study The primary outcome was significant, "Access to PTSD Coach supports improvement of psychological trauma-related symptoms."

2a-i) Problem and the type of system/solution
Describe the problem and the type of system/solution that is object of the study: intended as stand-alone intervention vs. incorporated in broader health care program? Intended for a particular patient population? Goals of the intervention, e.g., being more cost-effective to other interventions, replace or complement other solutions? (Note: Details about the intervention are provided in "Methods" under 5)

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Does your paper address subitem 2a-i? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "Self-guided interventions like PTSD Coach could not replace, but may complement, inperson treatment options as stand-alone interventions or additions to psychological or medical treatment." "To conclude, the efficacy, benefits and risks of self-management interventions for posttraumatic stress should be evaluated, especially if they are intended to be distributed without clinical support." Does your paper address subitem 2a-ii? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "However, the results from uncontrolled studies regarding PTSD Coach and decreased posttraumatic stress or depressive symptoms are inconsistent. The results from prior randomized controlled trial (RCT) studies of PTSD Coach differ too, perhaps due to differences in operationalization of outcomes and sample sizes." "To the best of our knowledge, no investigations of PTSD Coach report the presence or absence of deteriorated symptoms" and "Most researchers do not report the presence or absence of negative reactions to PTSD Coach". "The Swedish version of PTSD Coach is yet unexplored in a RCT." "We opted for an inactive waitlist to imitate the impact of access to PTSD Coach compared to situations when professional care may be temporarily unavailable, for example, during waitlist for psychological treatment or in the aftermath of mass disaster situations, to increase ecological validity." METHODS 3a) Description of trial design (such as parallel, factorial) including allocation ratio 3b) Important changes to methods after trial commencement (such as eligibility criteria), with reasons Does your paper address CONSORT subitem 2b? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "Therefore, we investigated whether access to PTSD Coach affected symptoms of posttraumatic stress (primary outcome), depression and somatic illness (secondary outcomes) in a randomized controlled trial. We also explored post-hoc response rates, clinically significant change, in posttraumatic stress, deterioration and remission rates of probable PTSD. We also investigated perceived helpfulness, satisfaction and negative reactions related to PTSD Coach." Does your paper address CONSORT subitem 3a? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "We conducted a RCT with a parallel group, mixed model design comparing the superiority of a self-management intervention to waitlist." We describe the"...equal allocation to access to PTSD Coach or waitlist (1:1)" in the randomization section of the methods.

4a) Eligibility criteria for participants
Does your paper address CONSORT subitem 3b? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "We made minor adjustments after the trial commenced. Participants who screened positive for alcohol or substance abuse in early remission (<12 months) with current treatment were accepted in the study" (from the participants section).

3b-i) Bug fixes, Downtimes, Content Changes
Bug fixes, Downtimes, Content Changes: ehealth systems are often dynamic systems. A description of changes to methods therefore also includes important changes made on the intervention or comparator during the trial (e.g., major bug fixes or changes in the functionality or content) (5-iii) and other "unexpected events" that may have influenced study design such as staff changes, system failures/downtimes, etc. [2].
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study No important changes, which could have influenced the study design, were made to the intervention or comparator after trial commencement. Does your paper address CONSORT subitem 4a? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "Adults (≥18 years) who resided in Sweden with Swedish verbal and written comprehension and ownership of a smartphone. Additional inclusion criteria were exposure to a potentially traumatic event in the past two years, according to DSM-5 criteria, and mild to severe posttraumatic stress symptoms (PTSD Checklist for DSM-5 total score ≥10). Exclusion criteria included potentially life-threatening or harmful living conditions/symptoms (recurring or ongoing traumatic event exposure, severe suicidal plans or ideation, current alcohol or drug abuse, lifetime manic/hypomanic episode and/or psychotic episode).
Additional exclusion criteria were current or pending psychotherapy, medical treatment changes and counter-indicative medication (such as benzodiazepines)."

4a-i) Computer / Internet literacy
Computer / Internet literacy is often an implicit "de facto" eligibility criterion -this should be explicitly clarified.
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study 4a-ii) Open vs. closed, web-based vs. face-to-face assessments: Open vs. closed, web-based vs. face-to-face assessments: Mention how participants were recruited (online vs. offline), e.g., from an open access website or from a clinic, and clarify if this was a purely webbased trial, or there were face-to-face components (as part of the intervention or for assessment), i.e., to what degree got the study team to know the participant. In online-only trials, clarify if participants were quasi-anonymous and whether having multiple identities was possible or whether technical or logistical measures (e.g., cookies, email confirmation, phone calls) were used to detect/prevent these.

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Does your paper address subitem 4a-ii? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "We recruited potential participants through social media advertisement" (from procedure section). Participants completed questionnaires online and partook in "a phone interview with a member of the research team", thus the study was not purely web-based but entirely remote. At one occasion per person, "we called all participants and offered the opportunity to ask questions regarding the study or technical support." We prevented the use of multiple identities by contacting all participants in the trial over the phone and email.

4a-iii) Information giving during recruitment
Information given during recruitment. Specify how participants were briefed for recruitment and in the informed consent procedures (e.g., publish the informed consent documentation as appendix, see also item X26), as this information may have an effect on user self-selection, user expectation and may also bias results.

4b) Settings and locations where the data were collected
subitem not at all important 1 2 3 4 5 essential Does your paper address subitem 4a-iii?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "We informed participants that participation was voluntary, confidential and how their data was managed" in writing, and participants were offerred to ask the research team questions over the phone or email before consenting, during the interview and phone call after randomization.
Participants were informed of the study on our website prior to entering the screening questionnaire. The full participant information was publicly available on the study website.

Does your paper address CONSORT subitem 4b? *
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "We collected data nationwide in Sweden" from our university, and participation was remote with online questionnaires and a phone interview.

4b-i) Report if outcomes were (self-)assessed through online questionnaires
Clearly report if outcomes were (self-)assessed through online questionnaires (as common in web-based trials) or otherwise. 5) The interventions for each group with sufficient details to allow replication, including how and when they were actually administered Does your paper address subitem 4b-i? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study

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We collected outcome data with online self-rating questionnaires. "Three months later participants received the follow-up questionnaire with the primary and secondary outcomes."

4b-ii) Report how institutional affiliations are displayed
Report how institutional affiliations are displayed to potential participants [on ehealth media], as affiliations with prestigious hospitals or universities may affect volunteer rates, use, and reactions with regards to an intervention.(Not a required item -describe only if this may bias results)
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study Social media advertisement linked to the university's study website. The university logo was displayed in the top corner of online questionnaires.
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "The mobile app PTSD Coach was developed by the Veterans' Affairs National Center for PTSD and Department of Defense's DHA Connected Health"

5-ii) Describe the history/development process
Describe the history/development process of the application and previous formative evaluations (e.g., focus groups, usability testing), as these will have an impact on adoption/use rates and help with interpreting results.
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "The Swedish version was adapted to a Swedish, civilian context from the American original." We refer to the prior development, pilot and feasibility studies in the introduction for further information about the development of the app.

5-iii) Revisions and updating
Revisions and updating. Clearly mention the date and/or version number of the application/intervention (and comparator, if applicable) evaluated, or describe whether the intervention underwent major changes during the evaluation process, or whether the development and/or content was "frozen" during the trial.
Describe dynamic components such as news feeds or changing content which may have an impact on the replicability of the intervention (for unexpected events see item 3b).
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study The app did not undergo development or major changes during the trial.

5-iv) Quality assurance methods
Provide information on quality assurance methods to ensure accuracy and quality of information provided [1], if applicable.
Does your paper address subitem 5-iv?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study The app content was checked by a psychologist prior to the trial. -v) Ensure replicability by publishing the source code, and/or providing screenshots/screen-capture video, and/or providing flowcharts of the algorithms used Ensure replicability by publishing the source code, and/or providing screenshots/screen-capture video, and/or providing flowcharts of the algorithms used. Replicability (i.e., other researchers should in principle be able to replicate the study) is a hallmark of scientific reporting.

Does your paper address subitem 5-v?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study No source code or screen shots are provided.

5-vi) Digital preservation
Digital preservation: Provide the URL of the application, but as the intervention is likely to change or disappear over the course of the years; also make sure the intervention is archived (Internet Archive, webcitation.org, and/or publishing the source code or screenshots/videos alongside the article). As pages behind login screens cannot be archived, consider creating demo pages which are accessible without login.

Does your paper address subitem 5-vi?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study The Swedish version of PTSD Coach was not publicly available (beta-version for select testers) during the trial, and therefore we cannot provide an open-access URL to the app.

5-vii) Access
Access: Describe how participants accessed the application, in what setting/context, if they had to pay (or were paid) or not, whether they had to be a member of specific group. If known, describe how participants obtained "access to the platform and Internet" [1]. To ensure access for editors/reviewers/readers, consider to provide a "backdoor" login account or demo mode for reviewers/readers to explore the application (also important for archiving purposes, see vi).
Does your paper address subitem 5-vii? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "App access participants received written instruction for downloading the app per email and instructed to use the app as they pleased. /.../ The waitlist participants received written notice per email that they would receive the app after the first follow-up assessment." Participants had to fulfill inclusion criteria without exclusion criteria. "During the trial, access to the Swedish version of PTSD Coach was restricted to App access participants through beta-testing" and was free. "Participants were compensated with gift cards to the cinema after completing the follow-up questionnaire. Participants who left the study or were excluded prior to the follow-up assessment received one gift card." Does your paper address subitem 5-viii? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "The mobile app PTSD Coach was developed by the Veterans' Affairs National Center for PTSD and Department of Defense's DHA Connected Health" and is inspired by cognitive behavioral therapy. "The resources in PTSD Coach are divided into four sections: Learn (psychoeducation about posttraumatic stress, treatment and coping in families), Track (symptom self-evaluation with rating history and automatic feedback), Manage symptoms (exercises for distress management inspired by cognitive behavioral therapy) and Get support (contact information for crisis resources, professional assessment and treatment, as well as platforms and advice for promoting social support). The self-guided exercises are voice, video or text-prompted."

5-ix) Describe use parameters
Describe use parameters (e.g., intended "doses" and optimal timing for use). Clarify what instructions or recommendations were given to the user, e.g., regarding timing, frequency, heaviness of use, if any, or was the intervention used ad libitum.
Does your paper address subitem 5-ix?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study Users were "instructed to use the app as they pleased. Participants who requested further guidance were encouraged to explore the app to identify helpful content." The optimal timing of use and intended doses of PTSD Coach are unknown.

5-x) Clarify the level of human involvement
Clarify the level of human involvement (care providers or health professionals, also technical assistance) in the e-intervention or as co-intervention (detail number and expertise of professionals involved, if any, as well as "type of assistance offered, the timing and frequency of the support, how it is initiated, and the medium by which the assistance is delivered". It may be necessary to distinguish between the level of human involvement required for the trial, and the level of human involvement required for a routine application outside of a RCT setting (discuss under item 21 -generalizability).
Does your paper address subitem 5-x?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "Seven days after randomization, we called all participants and offered the opportunity to ask questions regarding the study or technical support." We registered Android users manually for the beta-testing. This human involvement was provided by 5 people, "members of the research team who enrolled participants (the first author, a clinical psychologist and two psychology students) or randomized participants (the first author, a PhD and a clinical psychologist).

5-xi) Report any prompts/reminders used
Report any prompts/reminders used: Clarify if there were prompts (letters, emails, phone calls, SMS) to use the application, what triggered them, frequency etc. It may be necessary to distinguish between the level of prompts/reminders required for the trial, and the level of prompts/reminders for a routine application outside of a RCT setting (discuss under item 21 -generalizability). Does your paper address subitem 5-xi? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study No prompts were provided. "All participants responded to daily assessments during 21 days for a separate investigation" which included a question regarding whether they had used a self-management app (unspecified) in the past 24 hours.

5-xii) Describe any co-interventions (incl. training/support)
Describe any co-interventions (incl. training/support): Clearly state any interventions that are provided in addition to the targeted eHealth intervention, as ehealth intervention may not be designed as stand-alone intervention. This includes training sessions and support [1]. It may be necessary to distinguish between the level of training required for the trial, and the level of training for a routine application outside of a RCT setting (discuss under item 21 -generalizability. Does your paper address subitem 5-xii? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study No training was provided. Does your paper address CONSORT subitem 6a? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "The primary outcome posttraumatic stress was assessed at screening, baseline and followup with the PTSD Checklist for DSM-5 (PCL-5)." "The secondary outcome depressive symptoms was assessed at baseline and follow-up with the Patient Health Questionnaire (PHQ-9)." "The secondary outcome somatic symptoms was assessed at baseline and follow-up with the Patient Health Questionnaire -15 (PHQ-15)." 6a-i) Online questionnaires: describe if they were validated for online use and apply CHERRIES items to describe how the questionnaires were designed/deployed If outcomes were obtained through online questionnaires, describe if they were validated for online use and apply CHERRIES items to describe how the questionnaires were designed/deployed [9].
Does your paper address subitem 6a-i?

Copy and paste relevant sections from manuscript text
The questionnaires were not specifically validated for online use. Initial contact was made "through social media advertisement... /…/ Eligible participants provided an email..." The surveys were closed (apart from the screening questionnaire) and individual entries confirmed with the phone contact and individual contact information. Surveys were responded to "online" after following a personalized link. "Study data and email invitations were managed using REDCap electronic data capture tools." Surveys contained some adaptive questioning, no randomization of items. Number of items per page varied. Participants could change their answers before final submission with a back-button, or save their answers and return later. Incomplete questionnaires were analyzed (e.g. "We replaced single missing item ratings in the outcomes (n=25) with the individual's mean item rating", "Four App access participants did not complete the PTSD Coach Survey") 6b) Any changes to trial outcomes after the trial commenced, with reasons 6a-ii) Describe whether and how "use" (including intensity of use/dosage) was defined/measured/monitored Describe whether and how "use" (including intensity of use/dosage) was defined/measured/monitored (logins, logfile analysis, etc.). Use/adoption metrics are important process outcomes that should be reported in any ehealth trial.

Does your paper address subitem 6a-ii?
Copy and paste relevant sections from manuscript text Use of PTSD Coach was not defined, monitored or reported in this trial.

6a-iii) Describe whether, how, and when qualitative feedback from participants was obtained
Describe whether, how, and when qualitative feedback from participants was obtained (e.g., through emails, feedback forms, interviews, focus groups).

Does your paper address subitem 6a-iii?
Copy and paste relevant sections from manuscript text We do not present qualitative feedback in the paper.

7a) How sample size was determined
NPT: When applicable, details of whether and how the clustering by care provides or centers was addressed subitem not at all important 1 2 3 4 5 essential 7b) When applicable, explanation of any interim analyses and stopping guidelines Does your paper address CONSORT subitem 6b? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study No changes were made to trial outcomes. We "explored post-hoc response rates, clinically significant change, in posttraumatic stress, deterioration and remission rates of probable PTSD."

7a-i) Describe whether and how expected attrition was taken into account when calculating the sample size
Describe whether and how expected attrition was taken into account when calculating the sample size.

Does your paper address subitem 7a-i?
Copy and paste relevant sections from manuscript title (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "The required sample size of 160 participants was determined by an a-priori power analysis in G*Power version 3.1 based on the effect size of Cohen's d=0.5 in the pilot study and anticipated attrition up to 25%." 8a) Method used to generate the random allocation sequence NPT: When applicable, how care providers were allocated to each trial group 8b) Type of randomisation; details of any restriction (such as blocking and block size) 9) Mechanism used to implement the random allocation sequence (such as sequentially numbered containers), describing any steps taken to conceal the sequence until interventions were assigned Does your paper address CONSORT subitem 7b? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study We defined no interim analyses or stopping guidelines beforehand.
Does your paper address CONSORT subitem 8a? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "An external statistician generated the allocation sequence in R (Appendix 1)..." Does your paper address CONSORT subitem 8b? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "...a random number table with equal allocation to access to PTSD Coach or waitlist (1:1) with an un-stratified, block design fixed at 20 allocations" https://docs.google.com/forms/d/e/1FAIpQLSfZBSUp1bwOc_OimqcS64RdfIAFvmrTSkZQL2-3O8O9hrL5Sw/viewform?hl=en_US&formkey=dG… 32/52 10) Who generated the random allocation sequence, who enrolled participants, and who assigned participants to interventions 11a) If done, who was blinded after assignment to interventions (for example, participants, care providers, those assessing outcomes) and how NPT: Whether or not administering co-interventions were blinded to group assignment subitem not at all important 1 2 3 4 5 essential Does your paper address CONSORT subitem 9? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "The first author uploaded the random number table, without reviewing it, into the /.../ University REDCap randomization tool prior to data collection. /.../ Condition was revealed in the REDCap graphical user interface, non-blinded but unalterable, after randomization." Does your paper address CONSORT subitem 10? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "An external statistician generated the allocation sequence..." and five "members of the research team /.../ enrolled participants (the first author, a clinical psychologist and two psychology students) or randomized participants (the first author, a PhD and a clinical psychologist)."

11a-i) Specify who was blinded, and who wasn't
Specify who was blinded, and who wasn't. Usually, in web-based trials it is not possible to blind the participants [1, 3] (this should be clearly acknowledged), but it may be possible to blind outcome assessors, those doing data analysis or those administering co-interventions (if any).

11b) If relevant, description of the similarity of interventions
(this item is usually not relevant for ehealth trials as it refers to similarity of a placebo or sham intervention to a active medication/intervention) Does your paper address subitem 11a-i? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "Condition was /.../ non-blinded" to members of the research team and participants. We employed no blinded assessors in the study as outcomes were self-rated.
11a-ii) Discuss e.g., whether participants knew which intervention was the "intervention of interest" and which one was the "comparator" Informed consent procedures (4a-ii) can create biases and certain expectations -discuss e.g., whether participants knew which intervention was the "intervention of interest" and which one was the "comparator".
Does your paper address subitem 11a-ii?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "The waitlist participants received written notice per email that they would receive the app after the first follow-up assessment." The participants were aware that PTSD Coach was the intervention of interest.
12a) Statistical methods used to compare groups for primary and secondary outcomes NPT: When applicable, details of whether and how the clustering by care providers or centers was addressed subitem not at all important 1 2 3 4 5 essential Does your paper address CONSORT subitem 11b? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study No, it does not as we did not employ a placebo or sham intervention.

Does your paper address CONSORT subitem 12a? *
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "We analyzed data in R version 3.5.1 and 4.0.5 with linear mixed-effects modelling..."

12a-i) Imputation techniques to deal with attrition / missing values
Imputation techniques to deal with attrition / missing values: Not all participants will use the intervention/comparator as intended and attrition is typically high in ehealth trials. Specify how participants who did not use the application or dropped out from the trial were treated in the statistical analysis (a complete case analysis is strongly discouraged, and simple imputation techniques such as LOCF may also be problematic [4]).

12b) Methods for additional analyses, such as subgroup analyses and adjusted analyses X26) REB/IRB Approval and Ethical Considerations [recommended as subheading under "Methods"] (not a CONSORT item)
subitem not at all important 1 2 3 4 5 essential Does your paper address subitem 12a-i? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "All randomized participants were included in the intention-to-treat and per-protocol analyses. We replaced single missing item ratings in the outcomes (n=25) with the individual's mean item rating. Missing data for the outcomes at follow-up was assumed to be missing at random and addressed by using multiple imputations. We included baseline posttraumatic stress as a predictor and imputed each outcome in 500 datasets (10 iterations) with predictive mean matching (mice package v3.13.0 and miceadds package v3.11-6). We report pooled parameter estimates across all imputations." Does your paper address CONSORT subitem 12b? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "We tested post-hoc whether the number of participants that reported clinically significant improvement or deterioration in posttraumatic stress (±10-point difference on PCL from baseline to follow-up) or screened positive for PTSD (≥31 points on the PCL-5) at baseline and follow-up differed between conditions with χ2-tests. In addition, we explored whether remission from probable PTSD (from ≥31 to <31 points) or development of probable PTSD (from <31 to ≥31 points) differed between conditions with χ2 and Fisher's exact test." Does your paper address subitem X26-i?

X26-i) Comment on ethics committee approval
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "The regional ethical review board in Uppsala, Sweden approved the study procedures ( Figure 1) prior to data collection (Dnr 2018/319)."

x26-ii) Outline informed consent procedures
Outline informed consent procedures e.g., if consent was obtained offline or online (how? Checkbox, etc.?), and what information was provided (see 4a-ii). See [6] for some items to be included in informed consent documents.

Does your paper address subitem X26-ii?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "Eligible participants provided an email, received the consent form and provided written informed consent" online by checking checkboxes, indicating that they consented to participating in the study, that they consented to the data management as described in the study information, as well as provided their personal contact information (such as name, email, phone number) in free-text.

X26-iii) Safety and security procedures
Safety and security procedures, incl. privacy considerations, and any steps taken to reduce the likelihood or detection of harm (e.g., education and training, availability of a hotline)

RESULTS
13a) For each group, the numbers of participants who were randomly assigned, received intended treatment, and were analysed for the primary outcome NPT: The number of care providers or centers performing the intervention in each group and the number of patients treated by each care provider in each center 13b) For each group, losses and exclusions after randomisation, together with reasons Does your paper address subitem X26-iii?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "Consenting participants booked an appointment for a phone interview with a member of the research team to confirm eligibility and assess psychiatric symptoms." We assessed exclusion criteria during this interview. "Exclusion criteria included potentially lifethreatening or harmful living conditions/symptoms (recurring or ongoing traumatic event exposure, severe suicidal plans or ideation, current alcohol or drug abuse, lifetime manic/hypomanic episode and/or psychotic episode)." User privacy was protected by not obtaining objective user data or metrics.
Does your paper address CONSORT subitem 13a? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study We present the information in the Figure 1. Does your paper address CONSORT subitem 13b? (NOTE: Preferably, this is shown in a CONSORT flow diagram) * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study We present the information in Figure 1.

13b-i) Attrition diagram
Strongly recommended: An attrition diagram (e.g., proportion of participants still logging in or using the intervention/comparator in each group plotted over time, similar to a survival curve) or other figures or tables demonstrating usage/dose/engagement.

Does your paper address subitem 13b-i?
Copy and paste relevant sections from the manuscript or cite the figure number if applicable (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study No objective user data was recorded in this trial.
Does your paper address CONSORT subitem 14a? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "Enrollment began May 2019 and ended June 2020." The follow-up was completed November 2020. 14a-i) Indicate if critical "secular events" fell into the study period Indicate if critical "secular events" fell into the study period, e.g., significant changes in Internet resources available or "changes in computer hardware or Internet delivery resources" Does your paper address subitem 14a-i?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study We are unaware of any significant changes in Internet resources available or changes in hardware during the trial.
Does your paper address CONSORT subitem 14b? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study The trial was not ended prematurely. Does your paper address CONSORT subitem 15? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study We present information in Table 1.

15-i) Report demographics associated with digital divide issues
In ehealth trials it is particularly important to report demographics associated with digital divide issues, such as age, education, gender, social-economic status, computer/Internet/ehealth literacy of the participants, if known.

Does your paper address subitem 15-i? *
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study We present information in Table 1.

16-i) Report multiple "denominators" and provide definitions
Report multiple "denominators" and provide definitions: Report N's (and effect sizes) "across a range of study participation [and use] thresholds" [1], e.g., N exposed, N consented, N used more than x times, N used more than y weeks, N participants "used" the intervention/comparator at specific pre-defined time points of interest (in absolute and relative numbers per group). Always clearly define "use" of the intervention. subitem not at all important 1 2 3 4 5 essential 17a) For each primary and secondary outcome, results for each group, and the estimated effect size and its precision (such as 95% confidence interval) Does your paper address subitem 16-i? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "The intervention group (App access) had access to PTSD Coach, and the waitlist group (Waitlist) did not have access to PTSD Coach during 3 months." "We specified 3 separate multiple regression models a priori with the direct and interaction effect of Condition × Time on posttraumatic stress, depressive symptoms and somatic symptoms, respectively." We also present information in Table 3.

16-ii) Primary analysis should be intent-to-treat
Primary analysis should be intent-to-treat, secondary analyses could include comparing only "users", with the appropriate caveats that this is no longer a randomized sample (see 18-i).

Does your paper address subitem 16-ii?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study Intent-to-treat analyses are presented in the main body of text, subitem not at all important 1 2 3 4 5 essential 17b) For binary outcomes, presentation of both absolute and relative effect sizes is recommended Does your paper address CONSORT subitem 17a? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study The information is presented in Table 3. For posttraumatic stress, the "standardized mean difference was small, Cohen's d=-0.45, 95% CI -0.70 to -0.20." For depressive symptoms, the "standardized mean difference was small, Cohen's d=-0.35, 95% CI -0.62 to -0.07)." For somatic symptoms, the "standardized mean difference was trivial, Cohen's d=-0.13, 95% CI -0.38 to 0.12."

17a-i) Presentation of process outcomes such as metrics of use and intensity of use
In addition to primary/secondary (clinical) outcomes, the presentation of process outcomes such as metrics of use and intensity of use (dose, exposure) and their operational definitions is critical. This does not only refer to metrics of attrition (13-b) (often a binary variable), but also to more continuous exposure metrics such as "average session length". These must be accompanied by a technical description how a metric like a "session" is defined (e.g., timeout after idle time) [1] (report under item 6a).
Does your paper address subitem 17a-i?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study We did not record metrics of use or dosage in this trial.
18) Results of any other analyses performed, including subgroup analyses and adjusted analyses, distinguishing pre-specified from exploratory subitem not at all important 1 2 3 4 5 essential Does your paper address CONSORT subitem 17b? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study Effect sizes are not reported for the exploratory Chi-Square and Fisher's exact tests. We present information regarding the tests in Table 4.
Does your paper address CONSORT subitem 18? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study We present per-protocol analyses and analyses excluding contamination (such as use of other self-managments app apart from PTSD Coach) in Appendix 2. "The results from sensitivity analyses per protocol and excluding contamination (Appendix 2) rendered highly similar results."

18-i) Subgroup analysis of comparing only users
A subgroup analysis of comparing only users is not uncommon in ehealth trials, but if done, it must be stressed that this is a self-selected sample and no longer an unbiased sample from a randomized trial (see 16-iii).

Does your paper address subitem 18-i?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study We did not perform analyses of solely users.

19) All important harms or unintended effects in each group
(for specific guidance see CONSORT for harms) subitem not at all important 1 2 3 4 5 essential Does your paper address CONSORT subitem 19? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study We assessed negative effects of access to PTSD Coach among the intervention participants. "Thirty-six people reported 1 to 8 negative reactions that, on average, affected them moderately (m=2.07, sd=0.86); the average total sum was 7.44 (n=36, sd=6.91)." "...we detected no difference in deterioration between App access and Waitlist participants" regarding posttraumatic stress severity.

19-i) Include privacy breaches, technical problems
Include privacy breaches, technical problems. This does not only include physical "harm" to participants, but also incidents such as perceived or real privacy breaches [1], technical problems, and other unexpected/unintended incidents. "Unintended effects" also includes unintended positive effects [2].

Does your paper address subitem 19-i?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study We are not aware of any privacy breaches. Participants reported occasional minor bugs in the app during the trial. "Also, some intervention participants stated that they never used PTSD Coach, which may reflect that they did not receive the intervention." Does your paper address subitem 19-ii?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study We do not report qualitative feedback in this paper.
22-i) Restate study questions and summarize the answers suggested by the data, starting with primary outcomes and process outcomes (use) Restate study questions and summarize the answers suggested by the data, starting with primary outcomes and process outcomes (use). Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "We conclude that access to PTSD Coach during 3 months decreases posttraumatic stress and depressive symptoms, but not somatic symptoms, as compared to a waitlist control. Users perceived PTSD Coach as little to moderately helpful and moderately satisfactory. We found no evidence of symptom deterioration among users of PTSD Coach as compared to waitlist, and the most commonly reported negative reactions related to the evaluation of the app and its design."

22-ii) Highlight unanswered new questions, suggest future research
Highlight unanswered new questions, suggest future research.

Does your paper address subitem 22-ii?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "We have limited information regarding adherence to the intervention or use of PTSD Coach during the trial, and future studies would benefit from recording objective usage data or contextual information, such as when and where utilization of a self-management app successfully mitigates short-term distress. Future research into mechanisms of change and moderating processes would greatly advance the field and future design of effective mobile self-management interventions for populations in need. We also encourage others to explore the extent and persistency of negative effects in relation to psychological or selfmanagement interventions."

20-i) Typical limitations in ehealth trials
Typical limitations in ehealth trials: Participants in ehealth trials are rarely blinded. Ehealth trials often look at a multiplicity of outcomes, increasing risk for a Type I error. Discuss biases due to non-use of the intervention/usability issues, biases through informed consent procedures, unexpected events.
Does your paper address subitem 20-i? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "Nevertheless, the study design does not permit us to distinguish whether PTSD Coach might function as a placebo. Also, some intervention participants stated that they never used PTSD Coach, which may reflect that they did not receive the intervention." "We know that negative effects occurred, but not to what extent they persisted. Considering that the people who were lost to follow-up had elevated initial symptoms of posttraumatic stress and depression, negative reactions might be underrepresented. Assessment of negative reactions in the Waitlist condition would have enabled a controlled comparison." "However, lacking specificity of the symptom measurement could have introduced bias to the promising results: self-ratings on PCL-5 may not discriminate between posttraumatic stress and depressive symptoms."

21-i) Generalizability to other populations
Generalizability to other populations: In particular, discuss generalizability to a general Internet population, outside of a RCT setting, and general patient population, including applicability of the study results for other organizations

23) Registration number and name of trial registry
Does your paper address subitem 21-i?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study "Similar interventions may need adaptations to promote symptoms reduction among other genders or societal contexts." 21-ii) Discuss if there were elements in the RCT that would be different in a routine application setting Discuss if there were elements in the RCT that would be different in a routine application setting (e.g., prompts/reminders, more human involvement, training sessions or other co-interventions) and what impact the omission of these elements could have on use, adoption, or outcomes if the intervention is applied outside of a RCT setting.
Does your paper address subitem 21-ii?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study We did not employ prompts/reminders or training sessions. "...we advise that users are informed about the possibility of negative effects in order to make an informed choice before utilizing apps for mental health. Moreover, clinicians could inform users to what extent PTSD Coach may be beneficial or helpful to adjust expectations." 24) Where the full trial protocol can be accessed, if available 25) Sources of funding and other support (such as supply of drugs), role of funders X27) Conflicts of Interest (not a CONSORT item) Does your paper address CONSORT subitem 23? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study

NCT04094922, Clinical Trials
Does your paper address CONSORT subitem 24? * Cite a Multimedia Appendix, other reference, or copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study No full trial protocol is accessible at the moment.
Does your paper address CONSORT subitem 25? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study In addition to the usual declaration of interests (financial or otherwise), also state the relation of the study team towards the system being evaluated, i.e., state if the authors/evaluators are distinct from or identical with the developers/sponsors of the intervention.
Does your paper address subitem X27-i?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study We provide the information under Conflicts of interest ("None.") We are distinct from the developers of the intervention ("Veterans' Affairs National Center for PTSD and Department of Defense's DHA Connected Health").
As a result of using this checklist, did you make changes in your manuscript? * What were the most important changes you made as a result of using this checklist?
As I was presented this checklist after we had submitted for review, I was unable to correct information in the manuscript, but would be happy to revise changes accordingly during the review process.