Edinburgh Clinical NLP at SemEval-2024 Task 2: Fine-tune your model unless you have access to GPT-4
This work addresses the challenge of enhancing accuracy and consistency in clinical NLP tasks, but it is incremental as it builds on existing methods without surpassing GPT-4.
The study tackled the problem of improving Natural Language Inference systems for Clinical Trial Reports by evaluating various Large Language Models with strategies like Chain-of-Thought and Parameter-Efficient Fine-Tuning, finding that merging adapters increased F1 score by 0.0346 and consistency by 0.152, but GPT-4 outperformed in faithfulness and consistency with an average score of 0.8328.
The NLI4CT task assesses Natural Language Inference systems in predicting whether hypotheses entail or contradict evidence from Clinical Trial Reports. In this study, we evaluate various Large Language Models (LLMs) with multiple strategies, including Chain-of-Thought, In-Context Learning, and Parameter-Efficient Fine-Tuning (PEFT). We propose a PEFT method to improve the consistency of LLMs by merging adapters that were fine-tuned separately using triplet and language modelling objectives. We found that merging the two PEFT adapters improves the F1 score (+0.0346) and consistency (+0.152) of the LLMs. However, our novel methods did not produce more accurate results than GPT-4 in terms of faithfulness and consistency. Averaging the three metrics, GPT-4 ranks joint-first in the competition with 0.8328. Finally, our contamination analysis with GPT-4 indicates that there was no test data leakage.