Background and purpose - There is increasing evidence that several commonly performed surgical procedures provide little advantage over nonoperative treatment, suggesting that doctors may sometimes be inappropriately optimistic about surgical benefit when suggesting treatment for individual patients. We investigated whether attitudes to risk influenced the choice of operative treatment and nonoperative treatment. Methods - 946 Swedish orthopedic surgeons were invited to participate in an online survey. A radiograph of a 4-fragment proximal humeral fracture was presented together with 5 different patient characteristics, and the surgeons could choose between 3 different operative treatments and 1 nonoperative treatment. This was followed by an economic risk-preference test, and then by an instrument designed to measure 6 attitudes to surgery that are thought to be hazardous. We then investigated if choice of non-operative treatment was associated with risk aversion, and thereafter with the other variables, by regression analysis. Results - 388 surgeons responded. Nonoperative treatment for all cases was suggested by 64 of them. There was no significant association between risk aversion and tendency to avoid surgery. However, there was a statistically significant association between suggesting to operate at least 1 of the cases and a "macho" attitude to surgery or resignation regarding the chances of influencing the outcome of surgery. Choosing nonoperative treatment for all cases was associated with long experience as a surgeon. Interpretation - The discrepancy between available evidence for surgery and clinical practice does not appear to be related to risk preference, but relates to hazardous attitudes. It appears that choosing nonoperative treatment requires experience and a feeling that one can make a difference (i.e. a low score for resignation). There is a need for better awareness of available evidence for surgical indications.