Background <p>This study aimed to determine the effectiveness of loosely regulated online quizzes in evaluating students’ knowledge outcomes compared to a traditional summative examination, using Medical Bacteriology and Mycology as a model.</p> Methods <p>A retrospective review of the student’s academic performances was conducted (<i>n = </i>320), analyzing the quiz score as well as how each student did the quizzes. Each parameter was mapped back to the students’ actual summative score to evaluate the correlation.</p> Results <p>There was a strong correlation between the online quiz and the summative scores (<i>p</i> = 0.013). An in-depth analysis also shows that students who performed well in the summative examination had the following characteristics; [1] they tried to pass the online quizzes in the early attempts (<i>p &lt; </i>0.001), [2] continued to revisit the quizzes after passing (<i>p</i> = 0.011) and [3] tried further to improve their quiz scores (<i>p</i> = 0.002).</p> Conclusion <p>Although online quizzes cannot yet replace traditional examinations, they can be an effective tool to assess student’s competence, and careful monitoring of the quiz results can help identify students who may need extra attention. The results also suggest that diligence and intelligence are both important in Medical Bacteriology and Mycology.</p>