Negative Marking and the Student Physician--A Descriptive Study of Nigerian Medical Schools

There is considerable debate about the two most commonly used scoring methods, namely, the formula scoring (popularly referred to as negative marking method in our environment) and number right scoring methods. Although the negative marking scoring system attempts to discourage students from guessing in order to increase test reliability and validity, there is the view that it is an excessive and unfair penalty that also increases anxiety. Feedback from students is part of the education process; thus, this study assessed the perception of medical students about negative marking method for multiple choice question (MCQ) examination formats and also the effect of gender and risk-taking behavior on scores obtained with this assessment method.

This was a prospective multicenter survey carried out among fifth year medical students in Enugu State University and the University of Nigeria. A structured questionnaire was administered to 175 medical students from the two schools, while a class test was administered to medical students from Enugu State University. Qualitative statistical methods including frequencies, percentages, and chi square were used to analyze categorical variables. Quantitative statistics using analysis of variance was used to analyze continuous variables.

Inquiry into assessment format revealed that most of the respondents preferred MCQs (65.9%). One hundred and thirty students (74.3%) had an unfavorable perception of negative marking. Thirty-nine students (22.3%) agreed that negative marking reduces the tendency to guess and increases the validity of MCQs examination format in testing knowledge content of a subject compared to 108 (61.3%) who disagreed with this assertion (χ² = 23.0, df = 1, P = 0.000). The median score of the students who were not graded with negative marking was significantly higher than the score of the students graded with negative marking (P = 0.001). There was no statistically significant difference in the risk-taking behavior between male and female students in their MCQ answering patterns with negative marking method (P = 0.618).

In the assessment of students, it is more desirable to adopt fair penalties for discouraging guessing rather than excessive penalties for incorrect answers, which could intimidate students in negative marking schemes. There is no consensus on the penalty for an incorrect answer. Thus, there is a need for continued research into an effective and objective assessment tool that will ensure that the students' final score in a test truly represents their level of knowledge.