A hypothetical model was formulated to explore factors that influenced academic and clinical achievement for graduate-entry medical students completing their third year of university studies. Nine latent variables were considered including the students' background, previous successes with their undergraduate and postgraduate studies and their assessed ability to study graduate-entry medicine based on their scholastic aptitude and their interview selection scores. The academic and clinical achievement of 99 graduate-entry medical students were estimated by measuring their performance on two separate assessment procedures, a 150 item multiple choice examination and a 20 item objectively structured clinical evaluation (OSCE) test. These two assessments were taken across two years (to include two student groups) and were equated using Rasch scaling procedures. Models identifying causal pathways leading to academic and clinical achievement were tested using Partial Least Squares Path Analysis (PLSPAT). The study's results suggest that medical student achievement can be predicted by variables, which account for 6 to 22 per cent of the variance of scores that assess academic achievement and clinical performance at the third year level respectively. The most significant predictors and those which had direct influence on graduate-entry medical student achievement were: (a) student gender, undergraduate grade point average scores, type of undergraduate studies undertaken, and where those studies were carried out that were related to the OSCE scores, and (b) whether or not the graduate-entry medical students had pursued other studies prior to undertaking the medical course and age that were both negatively related to achievement on the multiple choice examination. Measures of performance at interview and student scores for GAMSAT that were used in the selection process were not related to the performance outcomes assessed. (Contains 3 figures.)