Background: Medical education research should aspire to illuminate the field beyond description ("What was done?") and justification ("Did it work?") research purposes to clarification studies that address "Why or how did it work?" questions. We aim to determine the frequency of research purpose in both experimental and non-experimental studies, and ascertain the predictors of clarification purpose among medical education studies presented at the 2012 Asia Pacific Medical Education Conference (APMEC). Methods: We conducted a systematic review of all eligible original research abstracts from APMEC 2012. Abstracts were classified as descriptive, justification or clarification using the framework of Cook 2008. We collected data on research approach (Ringsted et al., 2011), Kirkpatrick's learner outcomes, statement of study aims, presentation category, study topic, professional group, and number of institutions involved. Significant variables from bivariate analysis were included in logistic regression analyses to ascertain the determinants of clarification studies. Results: Our final sample comprised 186 abstracts. Description purpose was the most common (65.6%), followed by justification (21.5%) and clarification (12.9%). Clarification studies were more common in non-experimental than experimental studies (18.3% vs 7.5%). In multivariate analyses, the presence of a clear study aim (OR: 5.33, 95% CI 1.17-24.38) and nondescriptive research approach (OR: 4.70, 95% CI 1.50-14.71) but not higher Kirkpatrick's outcome levels predicted clarification studies. Conclusion: Only one-eighth of studies have a clarification research purpose. A clear study aim and non-descriptive research approach each confers a five-fold greater likelihood of a clarification purpose, and are potentially remediable areas to advance medical education research in the Asia-Pacific.