title: Daily morbidity records: recall and reliability.
abstract: Methodological issues concerning the collection and analysis of daily morbidity data in community studies in developing countries are discussed. The effects of recall period and inter-observer variation on symptom prevalence are considered in the context of a longitudinal study in The Gambia, in which prevalence fell by about half over 1-week's recall. In the same study, many infant-days were recorded separately on two occasions, allowing an assessment of reliability in this type of morbidity diary data. The implications of these findings both in terms of data quality and cost-effectiveness are discussed, with the conclusion that weekly interviews examining the previous week's morbidity on a day-by-day basis are operationally optimal.
authors.affiliation: Medical Research Council Laboratories, Banjul, Gambia.
authors.forename: P
authors.initials: P
authors.lastname: Byass
authors.forename: P W
authors.initials: PW
authors.lastname: Hanlon
mesh_terms: D016907:Adverse Drug Reaction Reporting Systems / Q000191:economics / Q000592:standards*; D003362:Cost-Benefit Analysis; D003625:Data Collection / Q000191:economics / Q000379:methods*; D003906:Developing Countries; D005714:Gambia / Q000453:epidemiology; D006801:Humans; D007223:Infant; D007407:Interviews as Topic / Q000379:methods*; D008137:Longitudinal Studies; D009017:Morbidity; D015588:Observer Variation; D011159:Population Surveillance / Q000379:methods*; D015995:Prevalence; D015203:Reproducibility of Results