Predictive power of UKCAT and other pre-admission measures for performance in a medical school in Glasgow: a cohort study

BACKGROUND The UK Clinical Aptitude Test (UKCAT) and its four subtests are currently used by 24 Medical and Dental Schools in the UK for admissions. This longitudinal study examines the predictive validity of UKCAT for final performance in the undergraduate medical degree programme at one Medical School and compares this with the predictive validity of the selection measures available pre-UKCAT. METHODS This was a retrospective observational study of one cohort of students, admitted to Glasgow Medical School in 2007. We examined the associations which UKCAT scores, school science grades and pre-admissions interview scores had with performance indicators, particularly final composite scores that determine students' postgraduate training opportunities and overall ranking (Educational Performance Measure - EPM, and Honours and Commendation - H&C). Analyses were conducted both with and without adjustment for potential socio-demographic confounders (gender, age, ethnicity and area deprivation). RESULTS Despite its predictive value declining as students progress through the course, UKCAT was associated with the final composite scores. In mutually adjusted analyses (also adjusted for socio-demographic confounders), only UKCAT total showed independent relationships with both EPM (p = 0.005) and H&C (p = 0.004), school science achievements predicted EPM (p = 0.009), and pre-admissions interview score predicted neither. UKCAT showed less socio-demographic variation than did TSS. CONCLUSION UKCAT has a modest predictive power for overall course performance at the University of Glasgow Medical School over and above that of school science achievements or pre-admission interview score and we conclude that UKCAT is the most useful predictor of final ranking.