title: Physical activity in rural South Africa--are current surveillance instruments yielding valid results?
authors.forename: Ian
authors.initials: I
authors.lastname: Cook
mesh_terms: D000328:Adult; D015444:Exercise; D005260:Female; D015438:Health Behavior; D006801:Humans; D009043:Motor Activity; D013019:South Africa; D011795:Surveys and Questionnaires