Abstract
INTRODUCTION: We aimed to assess contouring-related practices among US radiation oncologists and explore how access to and use of resources and quality improvement strategies vary based on individual- and organization-level factors. METHODS: We conducted a mixed methods study with a sequential explanatory design. Surveys were emailed to a random 10% sample of practicing US radiation oncologists. Participating physicians were invited to a semi-structured interview. Kruskal-Wallis and Wilcoxon rank-sum tests and a multivariable regression model were used to evaluate associations. Interview data were coded using thematic content analysis. RESULTS: Survey overall response rate was 24%, and subsequent completion rate was 97%. Contouring-related questions arise in ≥50% of clinical cases among 73% of respondents. Resources accessed first include published atlases (75%) followed by consulting another radiation oncologist (60%). Generalists access consensus guidelines more often than disease-site specialists (P = 0.04), while eContour.org is more often used by generalists (OR 4.3, 95% CI 1.2-14.8) and younger physicians (OR 1.33 for each 5-year increase, 95% CI 1.08-1.67). Common physician-reported barriers to optimizing contour quality are time constraints (58%) and lack of access to disease-site specialists (21%). Forty percent (40%, n = 14) of physicians without access to disease-site specialists indicated it could facilitate the adoption of new treatments. Almost all (97%) respondents have formal peer review, but only 43% have contour-specific review, which is more common in academic centres (P = 0.02). CONCLUSION: Potential opportunities to improve radiation contour quality include improved access to disease-site specialists and contour-specific peer review. Physician time must be considered when designing new strategies.