Answering MCQs: a study of confidence amongst medical students

Medical students at the beginning of their obstetrics and gynaecology module were asked to complete a multiple choice question paper from an earlier module. Half the students were asked to answer only those questions where they were certain of the answers. The other half were asked to answer all questions. The mean mark in the second group was 86% higher than that in the first group. A computer programme was written where multiple choice questions were asked in a standard true/false format but instead of a don't know alternative the students were asked to rate their degree of certainty in having answered correctly on a scale of 0 to 100. Five students completed a total of 45 multiple choice question papers (each with 20, 5-part questions) both before and towards the end of their obstetrics and gynaecology module. The mean mark increased by 68.5% over the course of the module reflecting the students' increased knowledge. Their mean certainty level only increased by 50%, suggesting that the students underestimated their newly acquired knowledge.