title: Empirical validation of an instrument to measure habitual physical activity in youth from Maputo, Mozambique.
abstract: To develop a questionnaire to assess habitual physical activity in Mozambican children and youth, a study with school youth of Maputo was done. The study included the assessment of usual activities, development of the questionnaire, and testing its validity and reliability. The questionnaire was initially based on anecdotal observations of the usual activities of this population, then a sample of 20 children was observed during 24 h and interviewed the day before with a model that asked the subjects about the time spent in each activity. Fifteen days later the same students were interviewed with the questionnaire in order to test its validity. After another 15 days, the reliability of the questionnaire was tested. To score the questionnaire, estimation of metabolic equivalents (METS) of the socioculturally specific activities was done. This was based on published tables and heart rate monitoring of the children performing the activities listed on the questionnaire. Intraclass correlations between time observed and time reported ranged form 0.06-0.80, demonstrating limited capacity of the children to report time. However, percentage of agreement between the observations and the questionnaire concerning activity levels was 83%. It was concluded that the questionnaire may be a useful instrument for assessing the patterns of physical activity of African youth and for classifying groups according to levels of activity. However, it has limited utility for estimating energy expenditure. Am. J. Hum. Biol. 12:437-446, 2000. Copyright 2000 Wiley-Liss, Inc.
authors.affiliation: Faculty of Physical Education and Sports Sciences, Universidade Pedagógica Maputo, Mozambique.
authors.forename: A.
authors.initials: A
authors.lastname: Prista
authors.forename: A.T.
authors.initials: AT
authors.lastname: Marques
authors.forename: J.A.R.
authors.initials: JA
authors.lastname: Maia