The numbers 1 to 25 in the upper row correspond to the 25 questions in the survey that are present in the appendix of the BMJOpen manuscript. The colon under 1A is not relevant as it concerns nonsurgeon members of the Dutch Spine Society who were excluded from analysis as they do not perform spinal fusion in practice. Further, question 4 had 5 options and for analysis was divided in 5 subquestions which could be answered with yes or no (1 or 0). This data file contains the answers of all members of the Dutch Spine Society. To get the right impression on decision making for spinal fusion in low back pain patients, we only analysed the answers from surgeons who do this kind of surgery, so answer to question 1 should be 1 (neurosurgeon) or 2 (orthopedic surgeon), other members were excluded. In addition, question 5 (how many fusions per year for low back pain?) should be answer 2,3,4 or 5. Those who answered a 1 (0 fusions for back pain per year) were excluded from analysis. Thus, excluding those who answered with a 3 to question 1 or with a 1 to question 5 were excluded, which will leave you with a database of 62 respondents which was used for analysis in our paper.