title: Measurement and invariance characteristics of psychosocial correlates of youth physical activity.
abstract: OBJECTIVE
  Physical inactivity needs to be strategically addressed from and throughout childhood and adolescence. The youth physical activity promotion model provides a comprehensive framework for understanding and promoting physical activity in youth. This study examined psychometric characteristics of the children's attraction to physical activity scale and the perceived physical competence scale, two frequently utilized instruments to measure the underlying predisposing factors emphasized in the youth physical activity promotion model.
  
  
  METHODS
  A cross-sectional correlational research design was utilized to address the research purposes.
  
  
  METHODS
  Participants (N=1563) were involved with a large school-based initiative involving 19 schools in two U.S. states. The children's attraction to physical activity and perceived physical competence scales were administered in the schools by the physical education teachers using a customized online platform. Confirmatory factory analysis and invariance model testing (i.e., configural, metric, and scalar invariances) were conducted with the Linear Structural Relations 8.8 software.
  
  
  RESULTS
  The results supported the multidimensionality of the children's attraction to physical activity scale and demonstrated that the 6-factor measurement model was invariant by gender and mostly invariant by school level (elementary, middle, high). The scalar non-invariance across school levels was attributed to weak psychometric properties in two of the children's attraction to physical activity subscales (i.e., peer acceptance and fun of physical exertion).
  
  
  CONCLUSIONS
  The findings support the utility of the children's attraction to physical activity and perceived physical competence for capturing predisposing factors within the youth physical activity promotion model but document the need for refinements in several key subscales.
authors.affiliation: Department of Kinesiology, Iowa State University, United States. Electronic address: slchen11@iastate.edu.
authors.forename: Senlin
authors.initials: S
authors.lastname: Chen
authors.affiliation: Department of Kinesiology, Iowa State University, United States.
authors.forename: Yang
authors.initials: Y
authors.lastname: Bai
authors.affiliation: Department of Kinesiology, Iowa State University, United States.
authors.forename: Gregory
authors.initials: G
authors.lastname: Welk
authors.affiliation: Department of Kinesiology, Iowa State University, United States.
authors.forename: Spyridoula
authors.initials: S
authors.lastname: Vazou
authors.affiliation: The Department of Health and Human Performance, University of Wisconsin at River Falls, United States.
authors.forename: Jodee
authors.initials: J
authors.lastname: Schaben
mesh_terms: D000293:Adolescent; D000367:Age Factors; D002648:Child; D003430:Cross-Sectional Studies; D015444:Exercise / Q000523:psychology*; D005260:Female; D006293:Health Promotion; D006801:Humans; D008297:Male; D008962:Models, Theoretical; D011594:Psychometrics; D012737:Sex Factors
keywords: Invariance testing; Physical activity promotion; Structural equation modeling