Presentation of pain drawings in questionnaire surveys: influence on prevalence of neck and upper limb pain in the community.

Pain drawings can be presented as either a blank or a pre-shaded manikin. This study sought to determine the effect of these two presentations on prevalence estimates of neck and upper limb pain (NULP), and their relationship to patterns of pain report. A postal questionnaire was sent to a stratified random sample of 10000 adults. It contained a blank body manikin and a pre-shaded neck and upper limb manikin screening question. Respondents answering positively to the pre-shaded manikin were asked about pain intensity, affect, disability and duration. Other measures included general health status (SF-12v2) and demographic questions. Adjusted response rate was 53.5%. Age-standardized 1-month period prevalence was 44.0% (crude prevalence 50.5%) for the screening question and 37.3% (crude prevalence 42.1%) for the blank manikin. There was 88% agreement between the pre-shaded manikin and the shading of corresponding areas on the blank manikin (kappa=0.76, 95% CI=0.74, 0.78). Of the 603 disagreements, 509 comprised no shading on the blank manikin but positive response to the pre-shaded manikin; they reported lower pain intensity, fewer days with pain, shorter time since initial onset and less disability than the 2030 reporting NULP on both manikins (P<0.001 in each case). The form of manikin presentation in a postal questionnaire can shift the reported prevalence of pain; a difference of 6.7% in our study. Furthermore, respondents only answering positively to a pre-shaded manikin form a group experiencing less severe NULP and less associated disability.