title: Development and evaluation of the Motivation to Limit Screen-time Questionnaire (MLSQ) for adolescents.
abstract: OBJECTIVE
  The aim of this study was to design and evaluate a brief scale to assess adolescents' motivation to limit their screen-time using a self-determination theory (SDT) framework.
  
  
  METHODS
  The development and evaluation of the Motivation to Limit Screen-time Questionnaire (MLSQ) involved three phases. In Phase 1, experts in SDT were asked to review the content validity of the MLSQ items. In Phase 2, adolescent boys (N=342, mean age=12.7 ±.5 years) completed the MLSQ and the factorial validity of the model was explored. In Phase 3, adolescent boys (N=48, mean age=14.3 ± 1.3 years) completed the MLSQ on two occasions separated by 1-week. Phases 2 and 3 were conducted in New South Wales, Australia in 2012.
  
  
  RESULTS
  Twenty four SDT experts reviewed the original scale items. Validity coefficients associated with six of the original eight items exceeded the threshold value (V>.68, p<.01). In Phase 2, the revised three-factor (9-items) model provided a good fit to the data (SRMR=.07, CFI=.96). The intraclass correlation (ICC) values were .67 for amotivation and .70 and .82 for controlled and autonomous motivation, respectively.
  
  
  CONCLUSIONS
  This study has provided preliminary evidence for the validity and reliability of the MLSQ in adolescent boys.
authors: Priority Research Centre in Physical Activity and Nutrition, School of Education, University of Newcastle, Newcastle, Australia. Electronic address: David.Lubans@newcastle.edu.au.
authors: D R
authors: DR
authors: Lubans
authors: C
authors: C
authors: Lonsdale
authors: R C
authors: RC
authors: Plotnikoff
authors: J
authors: J
authors: Smith
authors: K
authors: K
authors: Dally
authors: P J
authors: PJ
authors: Morgan
mesh_terms: D000293:Adolescent; D002648:Child; D005260:Female; D006801:Humans; D007389:Internal-External Control; D008297:Male; D008838:Microcomputers; D009042:Motivation; D009517:New South Wales; D000297:Psychology, Adolescent; D011594:Psychometrics / Q000706:statistics & numerical data; D011998:Recreation; D015203:Reproducibility of Results; D057185:Sedentary Behavior; D012737:Sex Factors; D012927:Social Control, Informal; D011795:Surveys and Questionnaires; D013690:Television
keywords: Adolescents; CFA; CFI; Confirmatory factor analysis; ICC; Intraclass correlation coefficient; MLSQ; Motivation; Motivation to Limit Screen-time Questionnaire; NSW; New South Wales; Questionnaire; RAI; Reliability; SDT; SRMR; Screen-time; Self-determination theory; TSRQ; Treatment Self-Regulation Questionnaire; V; Validity; comparative fit index; content validity coefficient; relative autonomy index; self-determination theory; standardized root mean square residual