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[Compliance and attrition in the longitudinal surveys in Africa]
1chippaux@ird.sn
Bulletin De La Societe De Pathologie Exotique (1990)
|February 20, 2007
Abstract:
Strength reduction can compromise the validity of prospective studies. Attrition of cohorts observed in Sub-Saharan Africa was measured from the data of the literature. Cohorts retained for this study were selected on operational criteria and favoured trials standardized according to CONSORT criteria's. Based on 28 surveys lasting from 1 month to 8 years, attrition follows a logarithmic reduction related to the duration. It seems especially influenced by the quality of the study organization and the rigorousness of the procedures.
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