title: Development and validation of a questionnaire for the assessment of physical activity in epidemiological studies in Sub-Saharan Africa.
abstract: OBJECTIVE
  To develop and validate a questionnaire for measuring physical activity within Sub-Saharan Africa. Methods We designed the Sub-Saharan Africa Activity Questionnaire (SSAAQ), based upon existing questionnaires and an activity survey carried out in Cameroon. The questionnaire targeted past-year occupation, walking/cycling and leisure-time activities, and was administered by trained interviewers on two occasions, 10-15 days apart to 89 urban and rural consenting Cameroonians aged 19-68 years. Reliability was assessed by inter-interview comparison and repeatability coefficients (standard deviation of the test-retest difference). Validation was performed against a 24-hour heart rate monitoring and accelerometer recording.
  
  
  RESULTS
  The questionnaire was highly reproducible (rho = 0.95; P < 0.001). The inter-interview difference did not differ significantly from 0, with a repeatability coefficient of 0.46-1.46 hours. Total energy expenditure from the questionnaire was significantly correlated to heart rate monitoring (rho = 0.41-0.63; P < 0.05) and accelerometer measures (rho = 0.60-0.74; P < 0.01). Subject's self ranking of their activity did not match the questionnaire's quartiles of activity.
  
  
  CONCLUSIONS
  The present study presents the design and confirms the reliability and validity of SSAAQ in a rural and urban population of Cameroon and shows that subject's self ranking of activity might not accurately serve epidemiological purpose.
authors.affiliation: Cameroon Essential Non-communicable Disease Health Intervention Project, Endocrine and Diabetes Unit, Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, Yaoundé, Cameroon.
authors.forename: E
authors.initials: E
authors.lastname: Sobngwi
authors.forename: J C
authors.initials: JC
authors.lastname: Mbanya
authors.forename: N C
authors.initials: NC
authors.lastname: Unwin
authors.forename: T J
authors.initials: TJ
authors.lastname: Aspray
authors.forename: K G
authors.initials: KG
authors.lastname: Alberti
mesh_terms: D000328:Adult; D017954:Africa South of the Sahara / Q000453:epidemiology; D000368:Aged; D004734:Energy Metabolism; D015444:Exercise; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D007899:Leisure Activities; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000379:methods; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires / Q000592:standards*