This study investigated the assessment of acute (<12 weeks duration) nonspecific low back pain (NSLBP) by primary care clinicians. The aims were to determine the methods used, whether methods differ across professional disciplines, and the extent to which clinicians assess across domains of health. Survey data were gathered from 651 primary care clinicians from six professional disciplines (Physiotherapy, Manipulative Physiotherapy, Chiropractic, Osteopathy, General Medicine, and Musculoskeletal Medicine). Descriptive statistics (proportions and frequency of use distributions) were used to describe assessment technique use, Mann-Whitney U tests were used to determine between-discipline differences in the use of each assessment technique, and Bonferroni-adjusted inferential confidence intervals were constructed to allow visual comparison of the use of assessment techniques from five health domains. The results indicate that the methods used by different professional disciplines to assess NSLBP vary considerably, as 44 out of 48 assessment techniques showed significantly different utilisation rates across professions. Furthermore, assessment across domains of health in this condition was variable, as clinicians commonly assess physical impairments and pain and less commonly assess activity limitation and psychosocial function (100% of clinicians very frequently or often assess physical impairment, 99% [95%CI 98-100%] assess pain, 21% [95%CI 15-27%] assess activity limitation, and 7% [95%CI 3-11%] assess psychosocial function). Adoption of greater standardisation of assessment by clinicians may require demonstration of the capacity of this standardisation to improve patient outcomes.