Hong Kong Med J 2023 Dec;29(6):557–60 | Epub 11 Dec 2023
© Hong Kong Academy of Medicine. CC BY-NC-ND 4.0
Large language models: implications of rapid evolution in medicine
Billy HH Cheung, MEd, FCSHK (Gen); Michael TH Co, MS, FCSHK (Gen)
Department of Surgery, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
Corresponding author: Dr Michael TH Co (mcth@hku.hk)
 Full paper in PDF
Large language models (LLMs), a kind of generative artificial intelligence, have ignited considerable interest since the release of OpenAI’s GPT-3.5 model in November 2022.1 These complex models have incited substantive dialogue within scientific communities due to their potential applications in various fields, including medicine. For example, a previous investigation confirmed ChatGPT’s ability to pass medical, legal, and business examinations with ease.2 3 Nonetheless, in a study by Salvagno et al,4 its limitations were revealed due to two major issues. First, a phenomenon referred to as ‘artificial hallucination’ arises where the LLM generates information that appears realistic but is, in fact, entirely fabricated and without any factual foundation due to imperfect training data and algorithms.4 Second, in the case of ChatGPT, its dataset being limited to information up to September 2021.5
However, breakthroughs are being made as these LLMs are updated to overcome these shortfalls. Shortly after the publication by Salvagno et al4 in which the GPT-3.5 model was used, the GPT-4 model was introduced on 14 March 2023, and demonstrated improved accuracy due to a larger dataset and multimodal functionality.6 This was further improved with a web-browsing function that was introduced on 13 May 2023, enabling almost borderless information access.7 These two major upgrades provided new abilities to ChatGPT that go some way towards overcoming its prior limitations. Hence, we have re-evaluated the performance and reliability of ChatGPT and compared these results with the findings of the original study by Salvagno et al.4
Results with the GPT-4 model with web access versus the GPT-3.5 model
By employing the same prompt used in the study by Salvagno et al (online supplementary Appendix 1),4 we observed that the GPT-4 model was able to locate, analyse, and summarise the articles8 9 10 in just 3 minutes and 42 seconds over a standard domestic internet connection. The model demonstrated its capability to accurately summarise studies and engage in an ongoing dialogue to examine the topic comprehensively (online supplementary Appendix 2). Remarkably, the model could also generate code for Visual Basic for Applications in Microsoft PowerPoint, thereby facilitating the near-autonomous creation of a slide with a summary table (Fig8 9 10). On reviewing the original research articles, we affirmed the accuracy of ChatGPT’s outputs. Compared with the response generated by the GPT-3.5 model in the article by Salvagno et al,4 which was completely fabricated, the improvements are notable. The output of Visual Basic for Applications also demonstrates the ability of ChatGPT to write programming code, which helps automate presentation preparation and improve the efficiency of information distribution. This confirms our hypothesis that the GPT-4 model contains significant enhancements that bring numerous potential applications in the field of medicine.

Figure. Summary of the three studies presented in a Microsoft PowerPoint slide directly generated from Visual Basic for Applications code by the GPT-4 model (table dimensions adjusted)8 9 10
Recent evolution of large language models
The trajectory of LLM development in recent years has been marked by significant advancements in functionality and sophistication, as covered in other major articles.11 12 The investigation by Salvagno et al,4 which used the GPT-3.5 model, revealed several limitations, raising questions about the applicability and reliability of LLMs in critical fields such as clinical medicine and scientific research. Nonetheless, the introduction of the GPT-4 model represented a key milestone. This new iteration brought a suite of enhancements, including improved accuracy and multimodal functionality, broadening the range of data types the model could interrogate, process, and integrate2 and thereby expanding the potential applications of LLMs.
In a further leap, the developers incorporated a web-browsing function that allows the model to access information beyond its built-in knowledge base, making it a more robust and versatile tool. In addition, many developers have begun building plugins to ChatGPT to allow access to other information sources, such as PDF (Portable Document Format) documents and specific databases.13
These advancements necessitate detailed and repeated assessment of the performance and reliability of LLMs. As the models continue to evolve, this continuous process of review and refinement is crucial to maximising their potential applications in medicine while also addressing their inherent limitations.
Utilisation of large language models in medicine
The potential applications of LLMs in medicine are numerous and may bring forth transformative changes not only in clinical research but also in practical settings and medical education. For example, because a substantial portion of clinical information is text-based, LLMs could easily be used to enhance the efficacy and precision of patient summaries and referrals.14 15 Moreover, by processing extensive text-based medical knowledge, LLMs could serve as invaluable clinical assistants. Recent local research has corroborated this by demonstrating how such models can improve diagnostic confidence and early commencement of appropriate treatment in medicine, even in complicated geriatric patients.16 The use of LLMs should improve work efficiency and accuracy, which in turn would allow clinicians to spend more time with patients, thereby improving communication, trust, and the standard of care.
Medical education represents another domain where the use of LLMs holds promise. The escalating demand for superior medical education stems from the growing need for more proficient doctors and the continuous expansion of medical knowledge across various specialties. Large language models can contribute to this by acting as teaching assistants for educators and providing customised learning support for students.17 For example, our recent work demonstrated the effectiveness of LLMs in the creation of examination questions.18 This suggests that LLMs can also play a pivotal role as learning aids for medical students, enabling tailored learning experiences and promoting active recall, thereby enriching the educational journeys of future doctors.
Limitations of the current GPT-4 model
While the advancements are promising and rapid, the current state of LLMs is still far from perfect. It took our team five attempts to obtain a summary of all three articles; in the other four attempts, ChatGPT failed to access the link for one of the articles, and on one occasion, it attempted to search for similar articles to finish its task. On examining the conversation and final output, some may argue that the output from ChatGPT lacks depth and insight. However, we did not encounter any profound hallucinations during the process, and the limitations we observed can be attributed to restricted access to the original articles and the fact that ChatGPT has to look for information from other sources.
In summary, the limitations of the GPT-4 model are still apparent. Nonetheless, the latest version might approach the capabilities of a junior resident or research assistant when performing similar tasks. The limitations might be overcome by allowing access to full articles, increasing the word limit of queries, and allowing more time for additional training, which all seem possible.
Future possibilities
The speed and accuracy of knowledge synthesis that LLMs offer has transformative potential for research, clinical care, and education. Perhaps in a few years, a doctor not utilising LLMs will be seen as outdated, akin to how someone who does not use the internet might be viewed now. Moor et al19 have proposed that, with the availability of LLMs and multimodal models, foundation generalist medical artificial intelligence models, developed from general LLMs with access to clinical training datasets, may be on the horizon. While many can see the potential of LLMs, others fear that their rapid development could jeopardise our role as physicians. A few years ago, AlphaGo, an artificial intelligence system that plays the board game Go and was trained by humans with supervised and reinforcement learning, defeated the world’s strongest human players 60 games to zero in January 2017.20 Not long after, AlphaGo Zero, a similar system that taught itself to play Go without human supervision, triumphed over the earlier version. Researchers found that the programme developed tactics that no human had discovered before. In a similar manner, could current LLMs, built upon artificial intelligence programmes with machine learning, follow a similar trajectory and surpass humans in the near future?
Potential for inequity and discrimination
Looking beyond the promising possibilities of LLMs, we can also see the potential for engendering inequality through uneven access. For instance, in regions like Hong Kong, where access restrictions on such models have been imposed,21 users must resort to virtual private networks to access these resources.
Financial constraints further exacerbate this inequality. More advanced iterations, such as the GPT-4 model, are exclusively available to paid subscribers. This creates a financial barrier by denying access to those unable to afford the subscription fees.
In addition, there is the contentious issue of preferential access, wherein certain institutions are granted early access to novel features before public release. This effectively tilts the playing field, creating an undue advantage for a select few.
When LLMs such as ChatGPT evolve into effective and potent tools, these disparities may incite social injustice. Moreover, such imbalances could further widen the scientific, technological, and economic progress gaps between different stakeholders, underscoring the urgent need for equitable distribution and access to these tools.
We are at a pivotal juncture in history where artificial intelligence and LLMs are becoming increasingly reliable and usable tools with the potential to revolutionise clinical practice, scientific discovery, and teaching. We encourage clinicians and researchers to harness the power of these tools, think creatively about their applications, and continually explore ways in which they can enhance our work, drive scientific advancements, and ultimately benefit humanity as a whole.
Author contributions
Concept or design: BHH Cheung.
Acquisition of data: Both authors.
Analysis or interpretation of data: Both authors.
Drafting of the manuscript: BHH Cheung.
Critical revision of the manuscript for important intellectual content: MTH Co.
Both authors had full access to the data, contributed to the study, approved the final version for publication, and take responsibility for its accuracy and integrity.
Conflicts of interest
Both authors have disclosed no conflicts of interest.
This commentary received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.
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