CONTEXT Understanding Self-Regulated Learning (SRL) is complicated because of the different measures used to identify the key SRL processes. There is a growing trend in applying event measures of SRL (microanalysis and trace) but aptitude measures (questionnaires) continue to be widely used in medical education. A major concern is whether aptitude measures are a valid approach to capture the dimensions of SRL processes. This study examined correlations between SRL microanalysis, SRL trace and Motivated Strategies for Learning Questionnaire (MSLQ) and how these measures were associated with biomedical science performance. METHODS A SRL microanalysis assessment interview was administered to 76 first year medical students individually whilst performing a biomedical science learning task. All written down materials by students were collected for further trace analysis. Students completed an MSLQ two weeks before completing their biomedical science course. Correlation analyses were used to determine the correlations between the three SRL assessment measures. Bivariate and multiple analyses were conducted to compare participants on different course or task performance using the three SRL assessment measures. RESULTS We identified that microanalytic metacognitive monitoring (k = 0.30, p < 0.001) and causal attributions (k = 0.17, p = 0.009) had statistically significant correlations with SRL trace strategy use. MSLQ self-efficacy was correlated with microanalytic self-efficacy (r = 0.39, P = 0.001). Bivariate tests showed that microanalytic metacognitive monitoring, causal attributions and adaptive inferences, and SRL trace strategy use had significant associations with task performance (p < 0.05). Microanalytic self-efficacy, metacognitive monitoring and causal attributions and SRL trace strategy use and MSLQ self-efficacy had significant associations with course performance (ps < 0.05). SRL trace strategy use measure and MSLQ subscales did not show significant associations with task and course outcomes in multiple analyses (p > 0.05). CONCLUSIONS Event measures, specifically SRL microanalysis had greater associations with both task and course outcomes compared with the MSLQ measure. We strongly recommend SRL microanalysis for the assessment of SRL in biomedical science learning. However, to fully understand medical students’ SRL we suggest that a multidimensional assessment approach that combines event and aptitude measures should be used.