Vanneman, Matthew Studies on the effectiveness of flipped classrooms: are we comparing apples to apples? [electronic resource] - Medical education 12 2017 - 1293-1294 p. digital Publication Type: Letter; Comment ISSN: 1365-2923 Standard No.: 10.1111/medu.13381 doi Subjects--Topical Terms: Education, MedicalHumansProblem-Based Learning