title: Self-reported activity and accelerometry in 2 behavior-maintenance trials.
abstract: OBJECTIVE
  To compare between accelerometry (MVPA-A) and self-reported activity (MVPA-SR) in activity-maintenance (Keep Active Minnesota; KAM) and weight loss-maintenance (Keep It Off; KIO) trials.
  
  
  METHODS
  Linear regression estimated moderation of study, treatment, or time on MVPA-A and MVPA-SR associations.
  
  
  RESULTS
  MVPA-A was similar between studies (KAM 119 minutes, KIO 112 minutes, p = .555), whereas MVPA-SR differed significantly (KAM 350 minutes, KIO 87 minutes, p < .0001). Only study moderated correlation between MVPA-A and MVPA-SR. MVPA-SR better predicted MVPA-A in KIO relative to KAM (p = .023).
  
  
  CONCLUSIONS
  Results suggest that self-presentation bias may influence validity of self-report in intervention studies with activity as a primary outcome. Researchers should select self-report to assess activity dimensions that objective measures capture poorly.
authors.affiliation: HealthPartners Institute for Education and Research, Minneapolis, MN, USA meghan.m.senso@healthpartners.com.
authors.forename: Meghan M
authors.initials: MM
authors.lastname: Senso
authors.affiliation: HealthPartners Institute for Education and Research, Minneapolis, MN, USA.
authors.forename: Christopher P
authors.initials: CP
authors.lastname: Anderson
authors.affiliation: HealthPartners Institute for Education and Research, Minneapolis, MN, USA.
authors.forename: A Lauren
authors.initials: AL
authors.lastname: Crain
authors.affiliation: HealthPartners Institute for Education and Research, Minneapolis, MN, USA.
authors.forename: Nancy E
authors.initials: NE
authors.lastname: Sherwood
authors.affiliation: HealthPartners Institute for Education and Research, Minneapolis, MN, USA.
authors.forename: Brian C
authors.initials: BC
authors.lastname: Martinson
mesh_terms: D061725:Accelerometry; D000368:Aged; D015992:Body Mass Index; D005260:Female; D015438:Health Behavior; D006801:Humans; D016014:Linear Models; D008297:Male; D055686:Metabolic Equivalent; D008875:Middle Aged; D008910:Minnesota; D009043:Motor Activity; D057566:Self Report; D011795:Surveys and Questionnaires; D016896:Treatment Outcome; D015431:Weight Loss