The aim of this study was to analyse the correspondence between answers to a questionnaire about trouble from the musculoskeletal system, answers in a personal interview and clinical findings indicating low back disorder. The questionnaire was answered by 1,773 construction workers. Out of those, 206 workers underwent interview and clinical examination. Among those who reported no lifetime LBT in the questionnaire 63% gave the same report in the personal interview and those were all assessed negative at a blind clinical examination. Of those reporting current LBT in the interview 80% (47/59) were clinically positive. The clinical criteria used in the examination seemed to indicate lumbar painful structures. Answers to a question about functional impairment were in conformity with clinical findings. As regards answers to a question about frequency of pain and a question, in the specific Nordic questionnaire for the low back, concerning inability to do normal work the correlation to clinical findings was less apparent. Reported inability to do normal work in the questionnaire corresponded only to 43% with reported sick-leave in the interview.