[Validation of the questionnaire for adolescents concerning ailments of lumbosacral region. Part I: reliability of questions about presence and character of pain].

The first part of the series of articles is dedicated to the process and the results of reliability testing of the questionnaire designed for pupils aged 13-18, the tested questions concerning ailments of the lumbosacral region (LBP) and their characteristics. 124 persons aged 13-17 took part in the research. The "test-retest" method was used, the questionannaires being filled in twice by every pupil in no more than 7-day period. Questions were asked about LBP, the accompanying ailments, the intensity of pain, the length of the episode, the cause of the beginning, the constant pain, the activities that worsen or reduce symptoms, the necessity of therapy, the presence of functional disorders connected with LBP, height, weight and basic ,,red flags" which could indicate pain of specific origin. Results that were obtained in the process of testing indicated that reasoning was invalid when based on questions about the length of episode (60% repeatable, rank correlation 0.3) and on questions about activities that worsen or reduce pain (respectively 34 i 35% repeatable answers). The rest of questions were found acceptably reliable.