In March and April 2021, 7,242 respondents were contacted by Sapio Research. Results on the incidence of hay fever are taken from looking at the proportion of people that were screened out of the survey versus those who continued because they suffered with hay fever (3,541).
The full survey with sufferers was then conducted among 3202 Hay fever sufferers and 339 Parents with children who suffer from hay fever, from an initial 7,242 respondents. Interviews were conducted online by Sapio Research in April 2021 using an email invitation and an online survey. Results of any sample are subject to sampling variation. The magnitude of the variation is measurable and is affected by the number of interviews and the level of the percentages expressing the results. In this particular study, the chances are 95 in 100 that a survey result does not vary, plus or minus, by more than 1.4 percentage points from the result that would be obtained if interviews had been conducted with all persons in the universe represented by the sample.