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Computer-assisted treatment may reduce therapist contact and costs and promote client participation. This meta-analysis examined the efficacy and acceptability of an unguided computer-assisted therapy in patients with obsessive-compulsive disorder (OCD) compared with a waiting list or attention placebo.
This study aimed to evaluate the effectiveness and adherence of computer-assisted self-help treatment without human contact in patients with OCD using a systematic review and meta-analysis approach.
Randomized controlled trials with participants primarily diagnosed with OCD by health professionals with clinically significant OCD symptoms as measured with validated scales were included. The interventions included self-help treatment through the internet, computers, and smartphones. We excluded interventions that used human contact. We conducted a search on PubMed, Cochrane Central Register of Controlled Trials, EMBASE, World Health Organization International Clinical Trials Registry Platform, and ClinicalTrials.gov, as well as the reference lists of the included studies. The risk of bias was evaluated using version 2 of the Cochrane risk-of-bias tool for randomized trials. We calculated the standardized mean differences for continuous outcomes and risk ratios for dichotomous outcomes. The primary outcomes were short-term improvement of OCD symptoms measured by validated scales and dropout for any reason.
We included 11 randomized controlled trials with a total of 983 participants. The results indicated that unguided computer-assisted self-help therapy was significantly more effective than a waiting list or psychological placebo (standard mean difference −0.47, 95% CI −0.73 to −0.22). Unguided computer-assisted self-help therapy had more dropouts for any reason than waiting list or psychological placebo (risk ratio 1.98, 95% CI 1.21 to 3.23). However, the quality of evidence was very low because of the risk of bias and inconsistent results among the included studies. The subgroup analysis showed that exposure response and prevention and an intervention duration of more than 4 weeks strengthen the efficacy without worsening acceptability. Only a few studies have examined the interaction between participants and systems, and no study has used gamification. Most researchers only used text-based interventions, and no study has used a mobile device. The overall risk of bias of the included studies was high and the heterogeneity of results was moderate to considerable.
Unguided computer-assisted self-help therapy for OCD is effective compared with waiting lists or psychological placebo. An exposure response and prevention component and intervention duration of more than 4 weeks may strengthen the efficacy without worsening the acceptability of the therapy.
PROSPERO (International Prospective Register of Systematic Reviews) CRD42021264644; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=264644
Obsessive-compulsive disorder (OCD) is characterized by intrusive and unwanted thoughts, urges, or images and repetitive behavior or mental acts [
The treatment of OCD involves psychotherapy and pharmacotherapy; however, psychotherapy may be a better treatment for OCD than pharmacotherapy [
Despite the presence of guidelines for the treatment of OCD, there are hindrances to therapy such as poor help-seeking behavior and inaccessible treatment. A study showed that more than half of patients with OCD have not received treatment [
Computer and internet-based treatment is a promising way to overcome these barriers. It can reduce therapist contact and costs and promote client participation in therapies conducted in a nonclinical setting [
Systematic reviews were conducted on studies including computer-assisted treatment for OCD, but there were limitations; Pearcy et al [
Excluding therapist contact and therapy using information technology will improve access to treatment. However, the effectiveness and adherence of computer-assisted interventions without human contact has not been examined through systematic review and meta-analysis. Additionally, the influence of several variables should be examined. For example, ERP is an effective and widely used component for OCD treatment, but therapist assistance is suggested to increase its effectiveness [
Therefore, this study aimed to evaluate the effectiveness and adherence of computer-assisted self-help treatment without human contact in patients with OCD using a systematic review and meta-analysis approach.
RCTs with participants primarily diagnosed with OCD according to the
We followed the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines [
The primary outcomes were short-term subjective improvement of OCD symptoms as measured by validated scales such as the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) and the Obsessive-Compulsive Inventory–Revised (OCI-R) and dropout for any reason at posttreatment. We defined short term as a period of 6 months.
Secondary outcomes were short-term response rate defined by validated scales and anxiety, depression, and QOL measured by validated scales. These outcomes measured at long term were also included in the secondary outcomes. We defined long term as a period greater than 6 months and gave priority to the longest end point.
We conducted a search on July 28, 2021, in PubMed, Cochrane Central Register of Controlled Trials, EMBASE, World Health Organization International Clinical Trials Registry Platform, and ClinicalTrials.gov, as well as the reference lists of the included studies (
Two authors independently examined the titles and abstracts of the references identified in the search and included them in the second screening if at least 1 author judged them to be included. We then obtained and examined the full text of the included studies using the first screening process. Finally, we included the studies that both reviewers felt should be included. If the 2 authors disagreed after a discussion, a third author was consulted to make a decision. We conducted data extraction in the same way as in the second screening process. We contacted the authors of the studies to obtain additional data or further clarification if needed.
We calculated the standardized mean differences (SMDs) and their 95% confidence intervals for continuous outcomes and risk ratios and their 95% confidence intervals for dichotomous outcomes. We used a random effects model.
The risk of bias was evaluated using version 2 of the Cochrane risk-of-bias tool for randomized trials (
Risk of bias in included studies.
We assessed heterogeneity using the
We performed the following subgroup analyses:
By type of psychotherapy included in the intervention (with or without ERP), as a systematic review showed the efficacy of ERP against OCD [
By intervention devices, as we hypothesized that device characteristics would influence the results. We planned to include portability with mobile phone, interaction with computer, and gamification. Portability may make it easy for participants to conduct ERP. Interaction and gamification may motivate participants to continue the intervention. However, no study included in this review used a mobile phone or gamification. As a result, we conducted a subgroup analysis with and without interaction with the system and intervention using a treatment manual via email or computer display. Interaction with the system means that participants can automatically get responses from a computer system without human contact
By study duration or number of sessions to examine the influence of duration. We conducted an analysis on studies with a duration equal to or less than 4 weeks and studies over 4 weeks, as the median and mode of the included study duration was 4 weeks. We could not conduct subgroup analysis by session because no studies reported the number of sessions conducted
By type of control arm, conducted as post hoc analysis, as a recent study showed that effect size may differ according to the control condition [
The quality of evidence for primary outcomes was evaluated according to the GRADE (Grading of Recommendations, Assessment, Development, and Evaluations) rating [
We identified 3130 references and excluded 2574 studies after assessing the title and abstracts. We retrieved 128 full-text papers, excluded 117 studies, and included 11 studies. We inspected the citations of the 11 studies and found 1 study to include. Finally, a total of 12 studies were included in the review, but we could not obtain additional data from the author of 1 study [
Preferred Reporting Items for Systematic Reviews and Meta-Analyses flow chart. CENTRAL: Cochrane Central Register of Controlled Trials; ICTRP: International Clinical Trials Registry Platform.
As seen in
Participants were recruited in European countries in 3 studies [
Interventions included computer-assisted cognitive training [
Characteristics of included studies.
Author; year; citation; country; study design | Participants | Interventions | Outcomes | |
|
Diagnosis; sex; medications | Age (years), mean (SD); baseline severity, mean (SD) |
|
|
Calkins et al [ |
Dx: OCI-Rb>15; Sex: CCTc arm: 54.2% women; PVTd arm 62.5%; medse: unclear | Age: CCT arm 27.9 (SD 14.1); PVT arm 30 (SD 13.8); Severity: OCI-R CCT arm 28.9 (SD 11.1); PVT arm 30.8 (SD 0.9) | CCT n=24; duration 2 weeks; exposure: no; cognitive modification: no; device: computer; interaction: no; gamification: no but a kind of task; PVT n=24; duration 2 weeks | OCI-R; BDI-IIf; PANASg; PSWQh |
Greist et al [ |
Dx: DSM-IVi; Sex: 42% women; meds: yes | Age: 39 (SD 12); Severity (Y-BOCSj): BT STEPSk arm 24.6 (SD 4.3); systematic relaxation arm 25.8 (SD 5.1) | BT STEPS n=74; duration 10 weeks; exposure: yes (ERPl); cognitive modification: unclear; device: computer-driven interactive voice response system and workbook; interaction: yes; gamification: no; Systematic relaxation n=75; duration 10 weeks; Clinician-guided behavior therapy | Y-BOCS; PGI-Im; CGI scalen; WSASo; HAM-Dp; SRIq medication status; treatment expectations; treatment satisfaction |
Haushildt et al 2016 [ |
Dx: DSM-IV; Sex: myMCT arm: 67.2% women; psychoeducation arm: 67.2%; Meds: yes | Age: myMCT arm 38.41 (SD 11.61); psychoeducation arm 39.64 (SD 9.88); Severity (Y-BOCS): myMCT arm 22.56 (SD 6.58); psychoeducation arm 21.45 (SD 6.42) | myMCT n=64; duration 4 weeks; Device: pdf file through email; exposure: no; cognitive modification: yes (metacognitive training, association splitting); interaction: no; gamification: no; Psychoeducation n=64; duration 4 weeks | Y-BOCS, BDIr, OBQs |
Moritz et al 2010 [ |
Dx: OCDt diagnosis made by health care professionals; Sex: myMCT arm: 62.8% women; waiting list arm: 72.1%; Meds: yes | Age: myMCT arm 34.95 (SD 11.87); waiting list arm 34.09 (SD 9.41); Severity (Y-BOCS): myMCT arm 18.6 (SD 6.86); waiting list arm 19.98 (SD 5.9) | myMCT n=43; duration 4 weeks; device: pdf file through email; exposure: no; cognitive modification: yes (metacognitive training); Waiting list n=43; duration 4 weeks. | Y-BOCS, OCI-R, BDI-SFu |
Moritz & Jelinek 2011 [ |
Dx: OCD diagnosis made by health care professionals; Sex: ASv arm: 56.5% women; waiting list arm: 78.3%; Meds: yes | Age: AS arm 36.0 (SD 9.81); waiting list arm 36.3 (SD 9.66); Severity (Y-BOCS): AS arm 21.96 (SD 8.17); waiting list arm 22.83 (SD 6.66) | AS n=43; duration 4 weeks; exposure: no; cognitive modification: yes (association splitting); device: treatment manual through email; interaction: no; gamification: no; Waiting list n=43; duration 4 weeks | Y-BOCS, OCI-R, BDI |
Moritz et al 2015 [ |
Dx: externally verified diagnosis of OCD; Sex: IBTw arm: 64% women; waiting list arm: 60%; Meds: yes | Age: IBT arm 36.88 (SD 13.14); waiting list arm 34.32 (SD 10.79); Severity (Y-BOCS): IBT arm 22.64 (SD 7.56); waiting list arm 21.48 (SD 7.38) | IBT n=25; duration 4 weeks; exposure: no; cognitive modification: yes (association splitting); device: treatment manual through email; interaction: no; gamification: no; Waiting list n=25; duration 4 weeks | Y-BOCS, OCI-R, ICQx, WHOQOL-BREFy |
Moritz et al 2018 [ |
Dx: diagnosis by a mental health specialist; Sex: myMCT arm: 71.4% women; waiting list arm: 82.9%; Meds: yes | Age: myMCT arm 38.17 (SD 11.96); waiting list arm 39.34 (SD 14.52); Severity (Y-BOCS): myMCT arm 23.09 (SD 5.93); waiting list arm 21.74 (SD 6.23) | myMCT n=36; duration 6 weeks; exposure: yes (ERP); cognitive modification: yes; other: mindfulness; device: treatment manual through email; interaction: no; gamification: no; Waiting list n=36; duration 6 weeks | Y-BOCS, OCI-R, PHQ-9z, Maladaptive and Adaptive Coping Scale, PSQ*aa |
Salemink et al 2015 [ |
Dx: DSM-IV-TR bb; Sex: CBM-Icc arm: 55.6% women; psychological placebo arm: 71.4%; Meds: yes | Age: CBM-I arm 15.6 (SD 2.4); psychological placebo arm 9 (SD 15.1); Severity (Children’s Y-BOCS): CBM-I arm 23.9 (SD 7.6); psychological placebo arm, 20.4 (SD 4.3) | CBM-I n=12; duration 1.6 weeks; exposure: yes (interoceptive exposure); cognitive modification: yes (cognitive bias modification training); device: computer; interaction: yes; gamification: no; Waiting list n=9; duration 1.6 weeks | Y-BOCS, OBQ-CVdd, RCADSee, CDIff |
Schneider et al 2015 [ |
Dx: diagnosis by a health care professional; Sex: COMETgg arm: 55.9% women; waiting list arm: 61.3%; Meds: yes | Age: COMET arm 37.47 (SD 10); psychological placebo arm 37.06 (SD 10.3); Severity (Y-BOCS): COMET arm 18.5 (SD 5.95); waiting list arm 19.84 (SD 5.99) | COMET n=34; duration 4 weeks; exposure: yes (interoceptive exposure); cognitive modification: yes (competitive memory training); device: pdf manual through email; interaction: no; gamification: no; Waiting list n=34; duration 4 weeks | Y-BOCS, OCI-R, BDI-SF, RSEShh |
Schröder et al 2020 [ |
Dx: Y-BOCS >7; Sex: iCBTii arm: 75% women; CAUjj arm: 78.13%; Meds: yes | Age: iCBT arm 41.45 (SD 12.15); CAU arm 38.98 (SD 11.55); Severity (Y-BOCS): iCBT arm 20.2 (SD 6.29); CAU arm 20.17 (SD 5.73) | iCBT n=64; duration 8 weeks; exposure: yes (ERP); cognitive modification: yes (metacognitive training); other, mindfulness; device: computer (text, video, audio, photo, illustration); interaction: yes; gamification: no; CAU n=64; duration 8 weeks | Y-BOCS, OCI-R, OBQ-44kk, WHOQOL-BREF |
Wootton et al 2019 [ |
Dx: Y-BOCS ≥14; Sex: ICBTkk arm: 81.5% women; waiting list arm: 81.3%; Meds: yes | Age: ICBT arm 34.03 (SD 10.8); waiting list arm 33.39 (SD 10.25); Severity (Y-BOCS): ICBT arm 22.52 (SD 4.91); waiting list arm 22.44 (SD 5.55) | ICBT n=90; duration 8 weeks; exposure: yes (ERP); cognitive modification: no; device: text-based online slides; interaction: no; gamification: no; Waiting list n=100; duration 8 weeks | Y-BOCS, DOCSll, PHQ-9 |
aRCT: randomized controlled trial.
bOCI-R: Obsessive-Compulsive Inventory–Revised.
cCCT: computerized cognitive control.
dPVT: peripheral vision training.
emeds: adjunctive medications.
fBDI-II: Beck Depression Inventory–Second Edition.
gPANAS: Positive and Negative Affectivity Scale.
hPSWQ: Penn State Worry Questionnaire.
iDSM-IV: Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition.
jY-BOCS: Yale-Brown Obsessive-Compulsive Scale.
kBT STEPS: Behavior Therapy Self-Help System.
lERP: exposure and response prevention.
mPGI-I: Patient Global Impression of Improvement.
nCGI scale: Clinical Global Impression scale.
oWSAS: Work and Social Adjustment Scale.
pHAM-D: Hamilton Depression Rating Scale.
qSRI: serotonin reuptake inhibitor.
rBDI: Beck Depression Inventory.
sOBQ: Obsessive Belief Questionnaire.
tOCD: obsessive-compulsive disorder.
uBDI-SF: Beck Depression Inventory–Short Form.
vAS: association splitting.
wIBT: inference-based therapy.
xICQ: Inferential Confusion Questionnaire.
yWHOQOL-BREF: Brief Quality of Life Questionnaire of the World Health Organization.
zPHQ-9: Patient Health Questionnaire.
aaPSQ: Patient Satisfaction Questionnaire.
DSM-IV-TR: Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision
ccCBM-I: Cognitive Bias Modification of Interpretation training.
ddOBQ-CV: Obsessive Belief Questionnaire–Child Version.
eeRCADS: Revised Child Anxiety and Depression Scale.
ffCDI: Children’s Depression Inventory.
ggCOMET: Competitive Memory Training.
hhRSES: Rosenberg Self-Esteem Scale.
iiiCBT: internet-based cognitive-behavioral therapy.
jjCAU: care-as-usual.
kkOBQ-44: Obsessive Belief Questionnaire–44 item.
llDOCS: Dimensional Obsessive-Compulsive Scale.
Most of the studies did not provide information on allocation sequence concealment. Of those who provided details, Schneider et al [
Six studies used waiting lists [
Most of the studies were missing more than 5% of the data, were unbalanced, and neglected to provide reasons for dropouts [
Primary efficacy outcome was measured by the self-rated Y-BOCS. It was unclear if knowledge of the intervention influenced the results.
We found the protocol for the RCT by Schröder et al [
Unguided computer-assisted self-help therapy was more effective than the waiting list and psychological placebo in terms of short-term subjective improvement of OCD symptoms (SMD −0.47, 95% CI −0.73 to −0.22; 9 studies; 659 participants). There was moderate heterogeneity (
Forest plot of short-term improvement of obsessive-compulsive disorder symptoms. ERP: exposure and response prevention.
Heterogeneity decreased to 24% after we excluded a study that reported a large number of dropouts before the intervention began [
We imputed standard deviations in 2 studies [
The subgroup analysis limited to those with ERP tended to strengthen the efficacy of unguided computer-assisted self-help therapy (SMD −0.64, 95% CI −1.02 to −0.27; 4 studies; 378 participants;
The majority of the studies only sent the treatment manual via email. The subgroup analysis limited to those studies with treatment manual showed that the intervention was more effective than the control arm (SMD −0.44, 95% CI −0.68 to −0.20; 6 studies; 442 participants;
The subgroup analysis limited to studies with some kind of interaction with systems showed no significant difference between the intervention and control groups (SMD −0.38, 95% CI –0.84 to 0.09; 3 studies; 233 participants;
In terms of duration of the intervention, studies with 4 weeks or less of intervention showed no significant difference between the intervention and control groups (SMD −0.20, 95% CI −0.45 to 0.06; 4 studies; 247 participants;
The subgroup analysis limited to studies with waiting list as control arm showed that the intervention was significantly more effective than the waiting list (SMD −0.56, 95% CI −0.91 to −0.22; 6 studies; 314 participants;
Unguided computer-assisted self-help therapy had more dropouts for any reason than waiting list or psychological placebo (risk ratio [RR] 1.98, 95% CI 1.21 to 3.23; 11 studies, 983 participants;
Heterogeneity decreased to 29% after excluding a study that had also been excluded from the sensitivity analysis of the short-term improvement of OCD symptoms [
The sensitivity analysis without studies targeted to child and adolescent [
Forest plot of dropout for any reason at posttreatment.
Funnel plot to assess for publication bias of dropout for any reason.
The subgroup analysis limited to those with ERP showed no significant difference between the intervention and control arms in dropout for any reason (RR 1.51, 95% CI 0.76 to 3.00; 4 studies; 539 participants;
The subgroup analysis limited to those using computer display showed no significant difference between the intervention and control group with respect to dropout for any reason (RR 0.85, 95% CI 0.67 to 1.08; 3 studies; 339 participants;
The subgroup analysis limited to studies with some kind of interaction with systems showed that the intervention arm had a significantly higher dropout for any reason than the control (RR 1.65, 95% CI 0.89 to 3.06; 3 studies; 233 participants;
In terms of duration of the intervention, studies with interventions of 4 weeks or less had significantly more dropouts than the control arm (RR 2.54, 95% CI 1.53 to 4.19; 7 studies; 444 participants;
The subgroup analysis by control arm showed that the intervention group had significantly more dropouts for any reason than control groups (waiting list control RR 1.79, 95% CI 1.24 to 2.58; 7 studies; 530 participants;
The unguided computer-assisted self-help therapy had a more short-term response than the waiting list/psychological placebo (RR 1.93, 95% CI 1.16 to 3.21; 2 studies; 249 participants). Heterogeneity was negligible (
One study evaluated short-term improvements in anxiety [
The improvement in depression was significantly greater in unguided computer-assisted self-help therapy than in the waiting list/psychological placebo (SMD −0.19, 95% CI −0.35 to −0.02; 7 studies; 560 participants). Heterogeneity was negligible (
There was no significant difference in short-term improvement of QOL between the unguided computer-assisted self-help therapy and waiting list/psychological placebo (MD 0.48, 95% CI −4.06 to 5.03; 2 studies; 134 participants). Heterogeneity was negligible (
No study has evaluated outcomes longer than 6 months. One study evaluated the Y-BOCS and Beck Depression Inventory–Second Edition (BDI-II) at 6 months [
We included 11 studies with a total of 983 participants. The results indicated that unguided computer-assisted self-help therapy was moderately more effective than waiting lists or a attention placebo, which was confirmed by sensitivity analyses. In addition, there were no significant differences in acceptability as measured by dropout for any reason between the 2 arms.
Subgroup analysis limited to studies with ERP or interventions of 4 weeks or less tended to strengthen the efficacy of unguided computer-assisted self-help therapy, although the number of included studies in these analyses was small. Moreover, there was no significant difference in efficacy between the 2 groups when the analysis was limited to studies using computer display or studies with the interaction between participants and systems.
For the acceptability measured by dropout for any reason, subgroup analysis limited to studies with ERP did not change the result, but the intervention arm had more dropouts when the analysis was limited to studies using treatment manual via email. In terms of intervention duration, analysis limited to studies of 4 weeks or less showed that the intervention arm had a greater number of dropouts than the control arm.
Short-term responses for secondary outcomes supported the efficacy of unguided computer-assisted self-help therapy; however, only 2 studies were included in the analysis. The short-term improvement of depression was greater with unguided computer-assisted therapy, but 2 studies reported no significant difference in the improvement of QOL and 1 study reported no difference in level of anxiety. There are no studies with long-term outcomes.
There were 3 systematic reviews and meta-analyses related with this study. All results favored the interventions. Firth et al [
In accordance with previous reviews, our review favored unguided computer-assisted self-help therapy against control arms, and the effect size was moderate (SMD −0.47). Although Pearcy et al [
This review reveals the acceptability of self-guided computer-assisted therapy for OCD measured by dropout for any reason. Future systematic reviews on self-guided OCD therapy should include the analysis of acceptability as one of the problems of self-guided therapy [
This study reconfirmed the importance of ERP in the treatment of OCD. The results of the meta-analysis showed that interventions with ERP were significantly more effective than those without ERP. However, human contact may strengthen the effect of ERP. The past meta-analyses on intervention with ERP compared with control condition showed that the SMDs of obsessive-compulsive symptoms were 1.16 and 0.74, respectively [
Our results showed that interventions with a duration over 4 weeks were more effective and tended to have fewer dropouts than interventions of 4 weeks or less. Avoiding interventions shorter than 4 weeks is recommended, considering the negligible heterogeneity of the results. However, it is unclear how long the intervention should be.
Several studies indicated that increment of treatment effect would decrease as the number of sessions increases [
One systematic review showed that highly rated anxiety apps contain gamification (32%) and social elements including chat and communication with others (46%) [
This study has several limitations. First, this study did not include active interventions as a comparison. While this would increase the number of included studies and precision, such an analysis may lead to an underestimation of the target intervention’s efficacy. Second, the overall risk of bias of the included studies was high, which led to downgrading the quality of evidence. However, this was unavoidable since a waiting list was the comparison arm, and the primary efficacy outcome was measured using a self-administered questionnaire. Future studies should use a psychological placebo to keep participants blinded to the intervention and the objective outcomes. Third, we did not consider sponsorship bias, which may favor the results of the intervention. However, as it seems that all authors developed the intervention, the results of this review may have overestimated the effect. The test of sponsorship bias should be initiated at the study design level. Fourth, the heterogeneity of results was moderate to considerable. This suggests that various factors are related to the effect of the computer-assisted self-help interventions in patients with OCD, such as the module, duration, modality of presenting intervention, gamification, and intervention. The number of studies on the computer-assisted self-help interventions in patients with OCD is still small, as shown in this study. More studies to explore and optimize the effect of the intervention should be conducted.
Our study suggests that unguided computer-assisted self-help therapy for OCD is effective compared to waiting lists or psychological placebo. An ERP component and intervention duration of more than 4 weeks may strengthen the efficacy without worsening the acceptability of the therapy.
However, the included studies did not effectively use the merits of computerization. Few studies have examined the interaction between participants and systems, and none of the studies used gamification. Furthermore, most studies only used text-based interventions. No study used a mobile device. Portability seems to be useful for intervention components, such as self-monitoring and in vivo exposure; therefore, future studies should examine these factors.
PRISMA checklist.
Search strategy.
Forest plot of short-term improvement of obsessive-compulsive disorder symptoms: subgroup analysis by treatment type.
Forest plot of short-term improvement of obsessive-compulsive disorder symptoms: subgroup analysis with and without interaction.
Forest plot of short-term improvement of obsessive-compulsive disorder symptoms: subgroup analysis by treatment duration.
Forest plot of short-term improvement of obsessive-compulsive disorder symptoms: subgroup analysis by control condition.
Forest plot of dropout for any reason at posttreatment: subgroup analysis by treatment type.
Forest plot of dropout for any reason at posttreatment: subgroup analysis with or without interaction.
Forest plot of dropout for any reason at posttreatment: subgroup analysis by treatment duration.
Forest plot of dropout for any reason at posttreatment: subgroup analysis by control condition.
Beck Depression Inventory–Second Edition
Behavior Therapy Self-Help System
cognitive behavioral therapy
Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition
Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision
exposure and response prevention
Grading of Recommendations, Assessment, Development, and Evaluations
mean difference
obsessive-compulsive disorder
Obsessive-Compulsive Inventory–Revised
Preferred Reporting Items for Systematic Reviews and Meta-Analyses
International Prospective Register of Systematic Reviews
quality of life
randomized controlled trial
risk ratio
standardized mean difference
Yale-Brown Obsessive-Compulsive Scale
We would like to thank Dr Ethan Sahker and Editage for English language editing. This work was supported by grant 21K157294 from the Japan Society for the Promotion of Science Grants-in-Aid for Scientific Research to HI. The funder had no role in study design, data collection, and analysis; decision to publish; or preparation of the manuscript.
HI, AT, and TAF were involved in study design and data interpretation. HI, AT, HN, NY, KK, HN, NT, YH, and YO were involved in data selection and extraction. All authors critically revised the report, commented on drafts of the manuscript, and approved the final report.
HI received consulting fees from Mitsubishi-Tanabe Pharma and honoraria for lectures from Mochida Pharmaceutical, Otsuka Pharmaceutical, and Kyowa Pharmaceutical. AT received lecture fees from Dainippon-Sumitomo, Janssen, Meiji-seika, Mitsubishi-Tanabe, and Otsuka. NY received a book royalty from Medical Friend; honoraria for lectures from Gakken Medical Support, Eisai, Meiji Seika Pharma, Mitsubishi-Tanabe Pharma, and Mochida Pharmaceutical; and honoraria for writings from Igaku-Shoin, Nikkei Business Publications, Maruzen Publishing, and Elsevier. He is a diplomate of the Academy of Cognitive and Behavioral Therapies, Secretary Board Member of the Japanese Association for Cognitive Therapy, and a member of the Japan Clinical Guideline Development Group for Anxiety Disorders and Obsessive-Compulsive Disorder. TAF reports grants and personal fees from Mitsubishi-Tanabe, personal fees from SONY, and grants and personal fees from Shionogi outside the submitted work. In addition, TAF has a patent 2020-548587 concerning smartphone CBT apps pending and intellectual properties for Kokoro-app licensed to Mitsubishi-Tanabe. All other authors declare no conflicts of interest.