No effect of recall period length on prevalence of self-reported haematuria in Schistosoma haematobium-endemic areas.

Assessing prevalence of haematuria by interview is commonly used as a rapid method to identify communities for mass treatment of Schistosoma haematobium infection. We analysed, using 21 published studies, to what extent the prevalence estimates of haematuria were affected by the length of the recall period for which respondents were requested to report symptoms. There was a strong positive association between prevalence of haematuria and infection, but no effect of recall period length. This suggests that the choice of recall period is of minor importance in control programmes or studies based on reported haematuria.