Within published reports, the prevalence of reported hearing difficulties is quite variable. In the present study, we have considered factors that could influence the apparent prevalence of hearing difficulties in the Welsh population, surveyed in a number of different studies. The first important factor to emerge was whether the questions were asked in the context of a general health approach (together with questions about other aspects of health), in which case the prevalence was usually less than 15%. When the same questions were posed in conjunction with a number of other questions on auditory function the prevalence was 20% or greater. Secondly, when a household survey approach is used, with one person being asked to respond on behalf of all members of the household, the prevalence among those reporting is markedly higher than among the other members of the household whose problems they are reporting.