MEASUREMENT OF THE FREQUENCY AND SEVERITY OF CHILDHOOD ACUTE RESPIRATORY-INFECTIONS THROUGH HOUSEHOLD SURVEYS IN NORTHERN GHANA

Background. Methodological issues in the design and interpretation of cross-sectional interview surveys of the prevalence of acute respirato ry infections (ARI) were assessed among young children. Methods. A cro ss-sectional survey was conducted in approximately 20 000 children in the north of Ghana. Approximately half were administered a questionnai re in which the initial questions about recent illnesses were direct q uestions about the presence or absence of three specific ARI-related s ymptoms (cough, rapid breathing, difficulty breathing), while the othe r half were administered a questionnaire which started with an open-en ded question on whether the child was ill, designed to elicit spontane ous responses. A 2-week recall period was used in addition to point pr evalence questions for half of the children in each group, while 4 wee ks was used for the other half. The results were compared with those f rom a longitudinal morbidity surveillance system in an adjacent popula tion of children. The repeatability of the responses to each of the sy mptoms/conditions was assessed in a subsample of the children. Results and conclusions. The point and period prevalence rates of ARI symptom s or conditions based on spontaneously elicited responses were more li kely to be valid than those based on prompted responses. Furthermore, using a 2-week recall period appeared to give more valid period preval ence rates than a 4-week recall period. The repeatability of the vario us ARI questions was not high (kappas 0.14 to 0.49), irrespective of t he questionnaire design. Whether these findings will also be true in o ther populations needs to be assessed,