The aim of this study was to compare self-administration with face-to-face interview in the investigation of low back pain in adolescents. Fifty-seven adolescents with low back pain (mean age 17.3 y; range 16-18) first completed a questionnaire and were then invited to an interview. Analysis included item completion, percentages of agreement and weighted kappa. Item completion rates were high and comparable between self-administration and interview. Information between both methods was analogous for severity and localization of problems, sleep behaviour, medical consultation and sports/leisure activities. Onset, progression, duration of low back pain and some items on the influence of movement/positions presented less comparable data. Conclusion: Even when two different methods of data acquisition are used, results suggest that the method used does not change the interpretation of results in the case of most items.