Purpose: Formative assessments, especially if spaced, encourage effective study habits such as retesting. The individual and combined effect of weekly formative assessments and cumulative assessments on final exam performance was studied. Methods: Students were placed into 6 groups by weekly formative assessment performance and practice exam utilization/performance. Students who scored below the median on weekly assessments comprised groups 1/3/5. Groups 2/4/6 scored above the median. Groups 1/2 did not use the practice exam. Groups 3/4 scored below the median on the practice exam while Groups 5/6 scored above. Multiple comparisons were made using ANCOVA. Results: Adjusted analysis showed weekly assessment and practice exam performance had a significant relationship with final exam performance (F[7,145]=18.765, p<0.0005). Groups 2/4/6 performed better on the final exam than groups 1/3/5 respectively (1v2, 80.8% vs 88.0%, p<0.0005 || 3v4, 83.4% vs 88.6%, p<0.0005 || 5v6, 84.1% vs 90.1%, p<0.0005). Group 1 performed worse than group 3 (80.8% vs 83.4%, p=0.072) and group 5 (80.8% vs 84.1%, p=0.047). Discussion: Performance on weekly formative assessments was predictive of final exam scores. Struggling medical students will benefit from extra cumulative practice exams while students who are excelling do not need extra practice.