Abstract
Low back pain is increasing considerably among adolescents, reaching proportions similar to the adult population. Flexibility (Flex) and muscle strength/resistance, components of Health-Related Physical Fitness (HRPF), seem to be associated with presence of low back pain. The aim of this study was to assess the ability of Flex and muscle strength/resistance in the screening of adolescents with low back pain and to propose cutoff points for these HRPF components. The study was conducted with 1.455 students aged 10-17 years randomly selected. Low back pain was estimated using a questionnaire. Flex was measured by the sit and reach test and muscle strength/resistance by the one minute sit up test. The analysis of the receiver operating characteristic (ROC) curve was used to identify the capacity of Flex and muscle strength/resistance for screening low back pain. To propose cutoffs points, the best balance between sensitivity and specificity was analyzed. The frequency of low back pain was 16.1 %, higher (p<0.05) among females (21.6%) than in males (10.5%). The ROC curve analysis indicated that Flex is able to identify girls more likely of having low back pain (p<0.05). Sit and reach test and the proposed cutoff points can be used as screening tool of female adolescents more likely of having low back pain.
Key words
Adolescents; Health; Low back pain; Roc curve