Comparison between GPT-4 and human raters in grading pharmacy students’ exam responses in Malaysia: a cross-sectional study

Purpose: Manual grading is time-consuming and prone to inconsistencies, prompting the exploration of generative artificial intelligence tools such as GPT-4 to enhance efficiency and reliability. This study investigated GPT-4’s potential in grading pharmacy students’ exam responses, focusing on the impact of optimized prompts. Specifically, it evaluated the alignment between GPT-4 and human raters, assessed GPT-4’s consistency over time, and determined its error rates in grading pharmacy students’ exam responses.Methods: We conducted a comparative study using past exam responses graded by university-trained raters and by GPT-4. Responses were randomized before evaluation by GPT-4, accessed via a Plus account between April and September 2024. Prompt optimization was performed on 16 responses, followed by evaluation of 3 prompt delivery methods. We then applied the optimized approach across 4 item types. Intraclass correlation coefficients and error analyses were used to assess consistency and agreement between GPT-4 and human ratings.Results: GPT-4’s ratings aligned reasonably well with human raters, demonstrating moderate to excellent reliability (intraclass correlation coefficient=0.617–0.933), depending on item type and the optimized prompt. When stratified by grade bands, GPT-4 was less consistent in marking high-scoring responses (Z=–5.71–4.62, P<0.001). Overall, despite achieving substantial alignment with human raters in many cases, discrepancies across item types and a tendency to commit basic errors necessitate continued educator involvement to ensure grading accuracy.Conclusion: With optimized prompts, GPT-4 shows promise as a supportive tool for grading pharmacy students’ exam responses, particularly for objective tasks. However, its limitations—including errors and variability in grading high-scoring responses—require ongoing human oversight. Future research should explore advanced generative artificial intelligence models and broader assessment formats to further enhance grading reliability.