This thesis covers:
(1) the Dutch physiotherapist guideline for diagnosing and treating spinal pain.
(2) The PRINS-study; Prevalence of RIsk groups in Neck and back pain patients according to the STarT back screening tool. This is a prospective cohort study including 284 patients whose primary complaint was low back pain or neck pain that consulted the physiotherapist or general practitioner. (3) The secondary analysis of the PACE-trial data concerning 1642 patients studying the efficacy of paracetamol taken regularly or as-needed compared with placebo to improve time to recovery from acute low back pain. We analyzed and described the magnitude of patient reported non-adherence with guideline-recommended care for acute low back pain, and to explore possible factors associated with non-adherence.