JMIR J Med Internet Res Journal of Medical Internet Research 1438-8871 JMIR Publications Toronto, Canada v22i7e21027 32721924 10.2196/21027 Corrigenda and Addenda Corrigenda and Addenda Correction: Optimizing Text Messages to Promote Engagement With Internet Smoking Cessation Treatment: Results From a Factorial Screening Experiment Graham Amanda L PhD 1
Innovations Center Truth Initiative 900 G Street, NW 4th Floor Washington, DC, 20001 United States 1 12024545938 agraham@truthinitiative.org
2 https://orcid.org/0000-0003-3036-9653 Papandonatos George D PhD 3 https://orcid.org/0000-0001-6770-932X Jacobs Megan A MPH 1 https://orcid.org/0000-0001-6526-964X Amato Michael S PhD 1 2 https://orcid.org/0000-0002-9769-957X Cha Sarah MSPH 1 https://orcid.org/0000-0003-3505-3164 Cohn Amy M PhD 4 https://orcid.org/0000-0001-9034-4293 Abroms Lorien C PhD 5 https://orcid.org/0000-0001-6859-283X Whittaker Robyn PhD 6 https://orcid.org/0000-0003-0901-9149 Innovations Center Truth Initiative Washington, DC United States Mayo Clinic College of Medicine and Science Rochester, MN United States Center for Statistical Sciences Brown University Providence, RI United States Oklahoma Tobacco Research Center University of Oklahoma Health Sciences Center Oklahoma City, OK United States Department of Prevention and Community Health Milken Institute School of Public Health The George Washington University Washington, DC United States National Institute for Health Innovation University of Auckland Auckland New Zealand Corresponding Author: Amanda L Graham agraham@truthinitiative.org 7 2020 28 7 2020 22 7 e21027 3 6 2020 3 6 2020 ©Amanda L Graham, George D Papandonatos, Megan A Jacobs, Michael S Amato, Sarah Cha, Amy M Cohn, Lorien C Abroms, Robyn Whittaker. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 28.07.2020. 2020

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 https://www.jmir.org/2020/4/e17734/

The authors of “Optimizing Text Messages to Promote Engagement With Internet Smoking Cessation Treatment: Results From a Factorial Screening Experiment” (J Med Internet Res 2020;22(4):e17734) noticed several errors in their published manuscript which had been introduced after proofreading. The following corrections have been implemented:

The symbols μ and φ were presented as m and f, respectively, in the following sentence of the Methods section; additionally, in this section, the negative sign was incorrectly subscripted:

SMDs for frequency counts were calculated as (m1−m2)/[f(m1+m2)]1/2, where m1 and m2 were the sample means of each comparison group.

This has been revised to:

SMDs for frequency counts were calculated as (μ1−μ2)/[φ(μ1+μ2)]1/2, where μ1 and μ2 were the sample means of each comparison group.

In the same paragraph, the negative sign was again incorrectly subscripted in the following sentence:

SMDs for binary outcomes were calculated as (p1−p2)/[p1×q1+p2×q2]1/2, where p1=1−q1 and p2=1−q2 were the sample outcome prevalence of each comparison group.

This has been revised to:

SMDs for binary outcomes were calculated as (p1−p2)/[p1×q1+p2×q2]1/2, where p1=1−q1 and p2=1−q2 were the sample outcome prevalence of each comparison group.

Additionally, due to a technical error the following sentence was published in the Results section of the Abstract:

As no SMD >0.30 was observed for main effects on any outcome, results suggest that for some outcomes, the combined intervention was stronger than individual factors alone.

This has been revised to:

As no SMD >0.30 was observed for main effects on any outcome, results suggest that for some outcomes, the combined intervention was stronger than individual factors alone.

The correction will appear in the online version of the paper on the JMIR website on July 28, together with the publication of this correction notice. Because this was made after submission to PubMed, PubMed Central, and other full-text repositories, the corrected article has also been resubmitted to those repositories.