title: [Reliability and validity of the PAQ-A questionnaire to assess physical activity in Spanish adolescents].
abstract: BACKGROUND
  Questionnaires are feasible instruments to assess physical activity (PA) in large samples. The aim of the current study was to evaluate the reliability and validity of the PAQ-A questionnaire in Spanish adolescents using the measurement of PA by accelerometer as criterion.
  
  
  METHODS
  In a sample of 82 adolescents, aged 12 to 17 years, 1-week PAQ-A test-retest was administered. Reliability was analyzed by the Intraclass Correlation Coefficient (ICC) and the internal consistency by the Cronbach's alpha Coefficient. Two hundred thirty-two adolescents, aged 13-17 years, completed the PAQ-A and wore the ActiGraph GT1M accelerometer during 7-days. The PAQ-A was compared against total PA and moderate to vigorous PA (MVPA) obtained by the accelerometer.
  
  
  RESULTS
  Test-retest reliability showed ICC = 0.71 for the final score of PAQ-A. Internal consistency was alpha = 0.65 in the first self-report, alpha = 0.67 in the retest in 82 adolescents sample, and alpha = 0.74 in the 232 adolescents sample. The PAQ-A was moderately correlated with total PA (rho = 0.39) and MVPA (rho= 0.34) assessed by the accelerometer. The PAQ-A obtained significantly moderate correlations in boys but not in girls against the accelerometer.
  
  
  CONCLUSIONS
  The PAQ-A questionnaire shows an adequate reliability and a reasonable validity for assessing PA in Spanish adolescents.
authors.affiliation: Departamento de Metabolismo y Nutrición. Grupo de Inmunonutrición, Instituto del Frío, Instituto de Ciencia y Tecnología de los Alimentos y Nutrición (ICTAN), Consejo Superior de Investigaciones Científicas (CSIC), Madrid, España.
authors.forename: David
authors.initials: D
authors.lastname: Martínez-Gómez
authors.forename: Vicente
authors.initials: V
authors.lastname: Martínez-de-Haro
authors.forename: Tamara
authors.initials: T
authors.lastname: Pozo
authors.forename: Gregory J
authors.initials: GJ
authors.lastname: Welk
authors.forename: Ariel
authors.initials: A
authors.lastname: Villagra
authors.forename: Marisa E
authors.initials: ME
authors.lastname: Calle
authors.forename: Ascensión
authors.initials: A
authors.lastname: Marcos
authors.forename: Oscar L
authors.initials: OL
authors.lastname: Veiga
mesh_terms: D000293:Adolescent; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D009043:Motor Activity; D015203:Reproducibility of Results; D013030:Spain; D011795:Surveys and Questionnaires