OBJECTIVES: To assess the use of prognostic patient factors and predictive tests in clinical decision making for spinal fusion in patients with chronic low back pain. DESIGN AND SETTING: Nationwide survey among spine surgeons. PARTICIPANTS: Surgeon members of the Dutch Spine Society were questioned on their treatment strategy for chronic low back pain. PRIMARY AND SECONDARY OUTCOME MEASURES: The surgeons’ opinion on the use of prognostic factors and tests for patient selection were addressed, and the degree of uniformity was assessed. In addition, the influence of surgeon specific factors, such as clinical experience and training, was determined. RESULTS: The comments from 62 surgeons (70% response rate) were analysed. Forty-four surgeons (71%) had extensive clinical experience. There was a statistically significant lack of uniformity of opinion in 7 of the 11 items on prognostic factors and 8 of the 11 items on predictive tests, respectively. Imaging was valued much higher than predictive tests, psychological screening, or patient preferences (all p<0.01). Apart from the use of discography and long multi-segment fusions, differences in training or clinical experience did not appear to be of significant influence on treatment strategy. CONCLUSIONS: The present survey showed a lack of consensus among spine surgeons on the use of predictive tests for patient selection. Prognostic patient factors were not consistently incorporated in their treatment strategy. Clinical decision making for spinal fusion to treat chronic low back pain does not have a uniform evidence base in practice. Future research should focus on identifying subgroups of patients for whom spinal fusion is an effective treatment. Only a reliable prediction of surgical outcome, combined with the implementation of individual patient factors, may enable the instalment of consensus guidelines in surgical decision making for chronic low back pain.