Predictive Validity of Diagnostic Tests on Graduate Students' Academic and Comprehensive Examination Performance

Diagnostic Test scores were assessed for predictive validity on Academic Performance (GWA) and Comprehensive Examination Performance in 291 Northeastern College graduates. The quantitative correlational research approach used secondary data and the Pearson Product-Moment Correlation Coefficient (r) to examine whether early assessments predicted academic success. Diagnostic Test scores showed a weak positive correlation with Academic Performance (r= 0.162, p = 0.006). Higher diagnostic scores slightly improve GWA outcomes, but the test has little predictive potential for program academic performance. This indicates that academic achievement is complex and shaped by contextual and motivational factors beyond cognitive capacity, necessitating integrated evaluation methods. The Diagnostic Test did not predict the high-stakes Comprehensive Examination Performance (r= 0.040, p=0.492). Academic Performance (GWA) did not connect with Comprehensive Examination Performance (r= 0.28, p = 0.633). Initial diagnostic tests and overall academic grades did not predict performance on the comprehensive exam. High-stakes tests require a cumulative application of knowledge and skills that early assessments and traditional grades cannot provide. The study recommends a more comprehensive, multifaceted assessment strategy that uses targeted preparatory programs to address skill deficiencies identified through diagnostic testing, thereby improving the prediction of graduate program success.