Efficacy and utilization of an acceptance and commitment therapy-based smartphone application for smoking cessation among Black adults: secondary analysis of the iCanQuit randomized trial
Corresponding Author
Margarita Santiago-Torres
Division of Public Health Sciences, Cancer Prevention Program, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
Correspondence
Margarita Santiago-Torres, Division of Public Health Sciences, Cancer Prevention Program, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue North, Seattle, WA 98109, USA. Email: [email protected].
Contribution: Conceptualization (lead)
Search for more papers by this authorKristin E. Mull
Division of Public Health Sciences, Cancer Prevention Program, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
Contribution: Conceptualization (equal), Formal analysis (lead), Methodology (equal)
Search for more papers by this authorBrianna M. Sullivan
Division of Public Health Sciences, Cancer Prevention Program, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
Contribution: Project administration (lead)
Search for more papers by this authorDiana Kwon
Division of Public Health Sciences, Cancer Prevention Program, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
Department of Psychology, University of Washington, Seattle, WA, USA
Search for more papers by this authorNicolle L. Nollen
Department of Preventive Medicine, University of Kansas School of Medicine, Kansas City, KS, USA
Contribution: Conceptualization (supporting)
Search for more papers by this authorMichael J. Zvolensky
Department of Psychology, University of Houston, Houston, TX, USA
HEALTH Institutive, University of Houston, Houston, TX, USA
MD Anderson Cancer Center, University of Texas, Houston, TX, USA
Contribution: Conceptualization (supporting)
Search for more papers by this authorJonathan B. Bricker
Division of Public Health Sciences, Cancer Prevention Program, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
Department of Psychology, University of Washington, Seattle, WA, USA
Contribution: Conceptualization (lead), Funding acquisition (lead), Methodology (lead), Resources (lead), Supervision (lead)
Search for more papers by this authorCorresponding Author
Margarita Santiago-Torres
Division of Public Health Sciences, Cancer Prevention Program, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
Correspondence
Margarita Santiago-Torres, Division of Public Health Sciences, Cancer Prevention Program, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue North, Seattle, WA 98109, USA. Email: [email protected].
Contribution: Conceptualization (lead)
Search for more papers by this authorKristin E. Mull
Division of Public Health Sciences, Cancer Prevention Program, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
Contribution: Conceptualization (equal), Formal analysis (lead), Methodology (equal)
Search for more papers by this authorBrianna M. Sullivan
Division of Public Health Sciences, Cancer Prevention Program, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
Contribution: Project administration (lead)
Search for more papers by this authorDiana Kwon
Division of Public Health Sciences, Cancer Prevention Program, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
Department of Psychology, University of Washington, Seattle, WA, USA
Search for more papers by this authorNicolle L. Nollen
Department of Preventive Medicine, University of Kansas School of Medicine, Kansas City, KS, USA
Contribution: Conceptualization (supporting)
Search for more papers by this authorMichael J. Zvolensky
Department of Psychology, University of Houston, Houston, TX, USA
HEALTH Institutive, University of Houston, Houston, TX, USA
MD Anderson Cancer Center, University of Texas, Houston, TX, USA
Contribution: Conceptualization (supporting)
Search for more papers by this authorJonathan B. Bricker
Division of Public Health Sciences, Cancer Prevention Program, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
Department of Psychology, University of Washington, Seattle, WA, USA
Contribution: Conceptualization (lead), Funding acquisition (lead), Methodology (lead), Resources (lead), Supervision (lead)
Search for more papers by this authorFunding information: National Cancer Institute, Grant/Award Number: R01CA192849; National Institute on Minority Health and Health Disparities to the University of Houston, Grant/Award Number: U54MD015946
Abstract
Background and aims
Black adults who smoke are less likely to seek treatment and to succeed in quitting compared with other racial groups. The lack of efficacious and engaging trials for smoking cessation further contributes to this disparity. This study explored whether an acceptance and commitment therapy (ACT)-based smartphone application (iCanQuit) was more efficacious for smoking cessation than a United States Clinical Practice Guidelines (USCPG)-based smartphone application (QuitGuide) among Black adults.
Design
Secondary analysis of a two-arm randomized trial with 12-month follow-up.
Setting
United States (US).
Participants
A total of 554 Black adults who smoke daily were recruited from 34 US states and enrolled between May 2017 and September 2018.
Interventions
Participants were randomized to receive iCanQuit (n = 274) or QuitGuide (n = 280) for 12 months.
Measurements
Smoking cessation outcomes were measured at 3, 6, and 12 months. The primary outcome was self-reported complete-case 30-day point prevalence abstinence (PPA) at 12 months. Secondary outcomes were 7-day PPA, missing-as-smoking imputation, multiple imputation, prolonged abstinence, and cessation of all tobacco products at 12 months. Study retention, treatment engagement, and change in ACT-based processes were also compared between arms.
Findings
Study retention was 89% at 12 months and did not differ by arm (P > 0.05). The complete-case 30-day PPA was 28% for iCanQuit versus 20% for QuitGuide at 12 months (odds ratio [OR] = 1.60; 95% confidence interval [CI] = 1.03, 2.46). Similar associations were observed for the missing-as-smoking imputation, although non-significant (25% iCanQuit vs 18% QuitGuide; OR = 1.50; 95% CI = 0.98, 2.30). iCanQuit vs QuitGuide participants were significantly more engaged with iCanQuit application as measured by the number of logins from baseline to 6 months (incidence rate ratio = 3.26; 95% CI = 2.58, 4.13). Increased acceptance of cues to smoke mediated the effect of treatment on cessation (indirect effect: OR = 0.20; 95% CI = 0.05, 0.29).
Conclusions
Among Black adults, an acceptance and commitment therapy-based smartphone application appeared to be more efficacious and engaging for smoking cessation than the United States Clinical Practice Guidelines-based QuitGuide application.
Supporting Information
| Filename | Description |
|---|---|
| add15721-sup-0001-Tables_S1-S2.docxWord 2007 document , 33.9 KB | Table S1 Change in ACT-based processes from baseline to 3 months as mediators of the effect of treatment on the primary cessation outcomes Table S2 Treatment engagement and satisfaction |
Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.
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