title: Do physical activity and dietary smartphone applications incorporate evidence-based behaviour change techniques?
abstract: BACKGROUND
  There has been a recent proliferation in the development of smartphone applications (apps) aimed at modifying various health behaviours. While interventions that incorporate behaviour change techniques (BCTs) have been associated with greater effectiveness, it is not clear to what extent smartphone apps incorporate such techniques. The purpose of this study was to investigate the presence of BCTs in physical activity and dietary apps and determine how reliably the taxonomy checklist can be used to identify BCTs in smartphone apps.
  
  
  METHODS
  The top-20 paid and top-20 free physical activity and/or dietary behaviour apps from the New Zealand Apple App Store Health & Fitness category were downloaded to an iPhone. Four independent raters user-tested and coded each app for the presence/absence of BCTs using the taxonomy of behaviour change techniques (26 BCTs in total). The number of BCTs included in the 40 apps was calculated. Krippendorff's alpha was used to evaluate interrater reliability for each of the 26 BCTs.
  
  
  RESULTS
  Apps included an average of 8.1 (range 2-18) techniques, the number being slightly higher for paid (M = 9.7, range 2-18) than free apps (M = 6.6, range 3-14). The most frequently included BCTs were "provide instruction" (83% of the apps), "set graded tasks" (70%), and "prompt self-monitoring" (60%). Techniques such as "teach to use prompts/cues", "agree on behavioural contract", "relapse prevention" and "time management" were not present in the apps reviewed. Interrater reliability coefficients ranged from 0.1 to 0.9 (Mean 0.6, SD = 0.2).
  
  
  CONCLUSIONS
  Presence of BCTs varied by app type and price; however, BCTs associated with increased intervention effectiveness were in general more common in paid apps. The taxonomy checklist can be used by independent raters to reliably identify BCTs in physical activity and dietary behaviour smartphone apps.
authors: National Institute for Health Innovation, University of Auckland, 261 Morrin Rd, Auckland 1072, New Zealand. a.direito@nihi.auckland.ac.nz.
authors: Artur
authors: A
authors: Direito
authors: Leila Pfaeffli
authors: LP
authors: Dale
authors: Emma
authors: E
authors: Shields
authors: Rosie
authors: R
authors: Dobson
authors: Robyn
authors: R
authors: Whittaker
authors: Ralph
authors: R
authors: Maddison
mesh_terms: D001521:Behavior Therapy / Q000379:methods*; D040421:Cell Phone; D004032:Diet; D055317:Evidence-Based Practice; D015444:Exercise; D006801:Humans; D063731:Mobile Applications / Q000592:standards*; D009520:New Zealand; D015203:Reproducibility of Results; D012985:Software Design