Fig. 1

Physician treatment recommendations by the highest level of supporting clinical evidence to treat by targeted therapy for each test. Physician treatment recommendations for targeted therapies were most frequent for patient tests detecting variants supported by level 1 companion diagnostic evidence for targeted therapy (26/89; 29%), followed by tests with variants supported by level 2 practice guideline evidence as the most actionable result (11/100; 11%), and tests with variants supported by level 3 clinical trial/off-label evidence as the most actionable result (15/419; 4%). Recommendations for chemotherapy and/or radiation were more common for tests with variants supported by level 3 evidence (193/419; 46%) than for patient test results with level 2 (32/100; 32%) or level 1 (23/89; 26%) evidence. Recommendations for clinical trials were infrequent for test results across all 3 evidence levels for patients with companion diagnostic level 1 (5/89; 6%), level 2 (2/100; 2%), and level 3 (28/419; 7%) evidence. Recommendations for immunotherapy were relatively frequent for tests with targeted therapy level 1 (14/89; 16%), level 2 (25/100; 25%) or level 3 (49/419; 12%) supporting evidence