y of low-back pain. Pan II: development of guidelines for trials of treatment in primary care. Spine IPhila Pa 1976) 1983;8:145-50. [16] Stuck' C, Daltrey L, Lung MH, et al. Measurement properties of a self- administered outcome measure in lumbar spinal stenosis. Spine (Phila Pa 1976) 1996;21:796-803. (