The Federal Aviation Administration assesses hazardous attitudes (HA) among pilots using the HA Scale, a 30-item questionnaire that quantifies HA such as macho, antiauthority, worry, resignation, and impulsivity, and has demonstrated the association of these attitudes with aviation risk. An association of HA scale and risk has been previously demonstrated in surgeons. The purpose of this study was to assess the influence of HA and other factors in treatment decision making among radiation oncologists (RO). The HA Scale was adapted for RO and the anonymous survey was sent to 809 RO in the city’s housing the top 25 cancer centers. Participants completed this scale, gave treatment recommendations in four cases designed to assess willingness to prescribe radiation (RT) courses with a higher biologically equivalent dose (BED), and were queried about their preferred option in routine practice in patients who mirror the focus of a Choosing Wisely campaign. Physician-reported demographic and treatment decision data were dichotomized in order to identify factors associated with higher BED treatment and compliance with Choosing Wisely recommendations using univariable (UVA) and multivariable (MVA) logistic regression analyses. A total of 139 responses (17.1%) were received, 103 of which were eligible for analysis. Of the respondents, 61 (60%) were male and 41 (40%) were female, and ages were evenly distributed. Eighty-five were from academic centers (83%). Median scores for macho, antiauthority, worry, resignation, and impulsivity were all below aviation thresholds for hazard (15, 9, 15, 12, & 15, respectively). On UVA, age >50 (odds ratio [OR] 3.65; 95% confidence interval [CI] 1.39-9.56], p=.008) and experience >5 years (OR 3.18, 95%; CI 1.08-9.37, p=.036) were associated with an increased likelihood of recommending higher BED RT, while HA and other demographic factors did not demonstrate an association. On MVA, responders >50 years old with >5-years’ experience were 4.45 times more likely to recommend higher BED RT (95% CI 1.32-15.0, p=.016). The macho attitude was negatively associated with compliance with Choosing Wisely recommendations (OR 0.12; CI 0.03-0.4; p=.001). Physicians who reported an experience of RT retreatment of the supraclavicular fossa without complication were more likely (OR 5.2, CI 1.55-17.61, p=.008) to recommend retreatment in medically unfit patients if they felt the complication was avoided due to careful planning rather than chance. To our knowledge this is the first study to examine and classify physician attitudes in the field of radiation oncology. RO did not display high levels of HA. However, the macho attitude was associated with nonadherence to Choosing Wisely recommendations. Other factors, such as increasing age and experience were associated with a higher propensity to recommend higher BED RT. This work lays the foundation for further efforts to identify factors associated with physician decision making in RO.