Catch Me If You Can: Identifying Fraudulent Physician Reviews with Large Language Models Using Generative Pre-Trained Transformers

Abstract: The proliferation of fake reviews of doctors has potentially detrimental consequences for patient well-being and has prompted concern among consumer protection groups and regulatory bodies. Yet despite significant advancements in the fields of machine learning and natural language processing, there remains limited comprehension of the characteristics differentiating fraudulent from authentic reviews. This study utilizes a novel pre-labeled dataset of 38048 physician reviews to establish the effectiveness of LLMs in classifying reviews. Specifically, we compare the performance of traditional ML models, such as logistic regression and support vector machines, to generative pre-trained transformer models. Furthermore, we use GPT4, the newest model in the GPT family, to uncover the key dimensions along which fake and genuine physician reviews differ. Our findings reveal significantly superior performance of GPT-3 over traditional ML models in this context. Additionally, our analysis suggests that GPT3 requires a smaller training sample than traditional models, suggesting its appropriateness for tasks with scarce training data. Moreover, the superiority of GPT3 performance increases in the cold start context i.e., when there are no prior reviews of a doctor. Finally, we employ GPT4 to reveal the crucial dimensions that distinguish fake physician reviews. In sharp contrast to previous findings in the literature that were obtained using simulated data, our findings from a real-world dataset show that fake reviews are generally more clinically detailed, more reserved in sentiment, and have better structure and grammar than authentic ones.