title: [Reproducibility and sensitivity of a questionnaire on physical activity in a Mexican population].
abstract: OBJECTIVE
  To assess the reproducibility and sensitivity of a physical activity questionnaire (PAQ) developed at Laval University, to detect differences in lean and obese individuals.
  
  
  METHODS
  A cross-sectional study was conducted at Mexico's National Institute of Medical Sciences and Nutrition, between January and May 1999. The PAQ was translated into Spanish and adjusted to the Mexican setting. The test-retest method was used to measure reliability, allowing a four-week interval between tests (n = 30 overweight subjects). To assess the questionnaire's sensitivity a group of young cadets (n = 18) was compared to a group of young civilians (n = 32). Concordance was measured through the intraclass correlation coefficient; test-retest was analyzed using the paired or unpaired Student's t test, as necessary.
  
  
  RESULTS
  The intraclass correlation coefficient was 0.86. The PAQ was able to show differences of more than 400 kcal/day (1674 kJ/day) and more than 4 kcal/kg/day (17 kJ/kg/day), among young people with high physical activity (t-test).
  
  
  CONCLUSIONS
  The PAQ is a sensitive and reliable instrument that can be used in the Mexican population. The English version of this paper is available at: http://www.insp.mx/salud/index.html
authors.affiliation: Clínica de Obesidad del Departamento de Endocrinología y Metabolismo, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Vasço de Quiroga No. 15, colonia Sección XVI, Tlalpan, 14000 México, D.F., México. jclalvar@aztlan.innsz.mx
authors.forename: J C
authors.initials: JC
authors.lastname: López-Alvarenga
authors.forename: S
authors.initials: S
authors.lastname: Reyes-Díaz
authors.forename: L
authors.initials: L
authors.lastname: Castillo-Martínez
authors.forename: A
authors.initials: A
authors.lastname: Dávalos-Ibáñez
authors.forename: J
authors.initials: J
authors.lastname: González-Barranco
mesh_terms: D000328:Adult; D015444:Exercise; D005260:Female; D006801:Humans; D008297:Male; D008800:Mexico; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D011795:Surveys and Questionnaires / Q000592:standards*