Reproducibility of a survey questionnaire for the investigation of low back problems in adolescents.

A test-retest design was used to investigate the reproducibility of the results obtained using a survey questionnaire for low back problems in adolescents. A 1-wk interval between test and retest was chosen. Participants were recruited from four schools. Selection of schools was based on geographic location, size of the school and educational level. Sixty-seven adolescents (mean age = 16.62 y; SD = 0.57; range = 16-18) suffering from low back problems agreed to participate. A questionnaire on perceived characteristics of back problems and functional limitations was designed. Item completion rate and the reproducibility of results were investigated by means of percentage agreement and (weighted) kappa. High levels of reproducibility were found for items that evaluated perceived characteristics of back problems and functional limitations (Kw = 0.70-0.93). Results suggest that the questionnaire used in the present study provided reproducible information. Detailed information on low back problems in adolescents could be obtained using this questionnaire.