title: Clearing asymptomatic parasitaemia increases the specificity of the definition of mild febrile malaria.
abstract: In clinical trials, the specificity of the disease endpoint is critical to an accurate estimate of vaccine efficacy. We used a logistic regression model to analyse parasite densities among children before and after treatment with antimalarials, in order to estimate the impact that clearing asymptomatic parasitaemia had on the specificity of the endpoint of febrile malaria. The malaria attributable fever fraction was higher after antimalarial treatment (i.e. fever and parasitaemia were more likely to be causally related), implying that drug treatment prior to monitoring decreased the misclassification of febrile malaria. In intervention studies with febrile malaria as an endpoint, clearing asymptomatic parasitaemia increases the study's power more effectively than raising the threshold parasitaemia.
authors.affiliation: Kenya Medical Research Institute, Centre for Geographical Medicine Research (Coast), Kenya. pbejon@kilifi.kemri-wellcome.org
authors.forename: Philip
authors.initials: P
authors.lastname: Bejon
authors.forename: Tabitha
authors.initials: T
authors.lastname: Mwangi
authors.forename: Brett
authors.initials: B
authors.lastname: Lowe
authors.forename: Norbert
authors.initials: N
authors.lastname: Peshu
authors.forename: Adrian V S
authors.initials: AV
authors.lastname: Hill
authors.forename: Kevin
authors.initials: K
authors.lastname: Marsh
mesh_terms: D000962:Antimalarials / Q000627:therapeutic use*; D001831:Body Temperature; D002648:Child; D002986:Clinical Trials as Topic; D005334:Fever / Q000453:epidemiology / Q000209:etiology* / Q000469:parasitology; D006801:Humans; D016015:Logistic Models; D008288:Malaria / Q000150:complications* / Q000453:epidemiology / Q000469:parasitology; D016778:Malaria, Falciparum / Q000453:epidemiology / Q000469:parasitology*; D018512:Parasitemia / Q000209:etiology* / Q000473:pathology; D012044:Regression Analysis
chemical_list: D000962:Antimalarials