This study is the first to investigate how an online course consisting solely of multiple-choice questions and detailed formative feedback comparesto an online course format that was previously shown to be highlyeffective. Specifically, a pure question-based learning (pQBL) version ofa course was compared to a question-based learning course (QBL)which consisted of the same questions and feedback as the pQBLcourse, but also included ordinary texts about the subject. To explorehow pQBL and QBL compared in terms of learning outcomes andcompletion time, 492 employees at the Swedish Employment Agencywere randomized to either a pQBL or a QBL version of a course aboutIT security. The results indicate that the pQBL course resulted in equallygood or better learning outcomes compared to the QBL course. Thisresult was robust to changes in how course quality was defined. Inaddition, participants completed the pQBL course slightly faster.Because a pQBL course requires less resources to produce, there arebenefits to relying on the pQBL method when teachers or studentshave limited time. Further benefits that come with the flexibility of thepQBL method are discussed