Prevalence of childhood cough in epidemiological studies: does it matter which question we use?

ABSTRACT We assessed how prevalence estimates of cough in 6-17-year-olds vary depending on the question asked in the population-based Luftibus in the school (LUIS) study. 3427 parents answered three different questions on cough. The prevalence of parent-reported cough varied substantially depending on the question: 25% of parents reported cough without a cold, 11% dry night cough and 5% that their child coughs more than other children. There was only partial overlap with 3% answering yes to all questions. This suggests that the exact question used to assess cough strongly affects prevalence estimates and must be taken into account when comparing studies.