title: Harnessing the Question-Behavior Effect to Enhance Colorectal Cancer Screening in an mHealth Experiment.
abstract: To assess whether asking questions about a future behavior changes this behavior (i.e., the question-behavior effect) when applied to a population-level intervention to enhance colorectal cancer screening.
  
  
  
  In 2013, text-message reminders were sent to a national sample of 50 000 Israeli women and men aged 50 to 74 years following a fecal occult blood test invitation. Participants were randomized into 4 intervention groups (2 interrogative reminders, with or without reference to social context; 2 noninterrogative reminders, with or without social context) and a no-intervention control group. The outcome was fecal occult blood test uptake (n = 48 091, following attrition).
  
  
  
  Performance of fecal occult blood test was higher in the interrogative-reminder groups than in the other 3 groups (odds ratio = 1.11; 95% confidence interval = 1.05, 1.19); the effect size was small, varying in the different group comparisons from 0.03 to 0.06.
  
  
  
  The question-behavior effect appears to be modestly effective in colorectal cancer screening, but the absolute number of potential screenees may translate into a clinically significant health promotion change.
authors.affiliation: Lea Hagoel, Nili Stein, and Gad Rennert are with the Department of Community Medicine and Epidemiology, Carmel Medical Center and Faculty of Medicine, Technion, Haifa, Israel. Efrat Neter is with the Department of Behavioral Sciences, Ruppin Academic Center, Emeq Hefer, Israel.
authors.forename: Lea
authors.initials: L
authors.lastname: Hagoel
authors.affiliation: Lea Hagoel, Nili Stein, and Gad Rennert are with the Department of Community Medicine and Epidemiology, Carmel Medical Center and Faculty of Medicine, Technion, Haifa, Israel. Efrat Neter is with the Department of Behavioral Sciences, Ruppin Academic Center, Emeq Hefer, Israel.
authors.forename: Efrat
authors.initials: E
authors.lastname: Neter
authors.affiliation: Lea Hagoel, Nili Stein, and Gad Rennert are with the Department of Community Medicine and Epidemiology, Carmel Medical Center and Faculty of Medicine, Technion, Haifa, Israel. Efrat Neter is with the Department of Behavioral Sciences, Ruppin Academic Center, Emeq Hefer, Israel.
authors.forename: Nili
authors.initials: N
authors.lastname: Stein
authors.affiliation: Lea Hagoel, Nili Stein, and Gad Rennert are with the Department of Community Medicine and Epidemiology, Carmel Medical Center and Faculty of Medicine, Technion, Haifa, Israel. Efrat Neter is with the Department of Behavioral Sciences, Ruppin Academic Center, Emeq Hefer, Israel.
authors.forename: Gad
authors.initials: G
authors.lastname: Rennert
mesh_terms: D000368:Aged; D015179:Colorectal Neoplasms / Q000175:diagnosis*; D055088:Early Detection of Cancer / Q000379:methods*; D005260:Female; D006293:Health Promotion / Q000379:methods*; D006801:Humans; D007557:Israel; D008297:Male; D008875:Middle Aged; D008960:Models, Psychological; D009780:Occult Blood; D016017:Odds Ratio; D017010:Reminder Systems; D012959:Socioeconomic Factors; D017216:Telemedicine; D060145:Text Messaging