Comparative evaluation of multimodal large language models for Mayo Endoscopic Subscore grading in ulcerative colitis

Table 4 Segment-wise performance comparison of five multimodal large language models in phase B

Segments	Models	Accuracy	Precision	Recall	F1 score	Cohen’s κ	MAE	MSE	RMSE	SD	CV	r value1
Ileocecal region	Gemini-2.5-Pro	0.426	0.752	0.426	0.478	0.226	0.787	1.213	1.101	0.77	1.508	0.606
	Grok-4	0.362	0.727	0.362	0.456	0.144	1.043	1.979	1.407	1.031	2.018	0.453
	GPT-4o	0.532	0.643	0.532	0.566	0.25	0.574	0.787	0.887	0.79	1.547	0.639
	GPT-5	0.596	0.718	0.596	0.625	0.356	0.426	0.468	0.684	0.593	1.162	0.751
	Qwen-VL-Max	0.298	0.547	0.298	0.339	0.058	0.957	1.468	1.212	0.956	1.872	0.315
Ascending colon	Gemini-2.5-Pro	0.49	0.739	0.49	0.514	0.309	0.673	1.041	1.02	0.766	1.211	0.665
	Grok-4	0.388	0.641	0.388	0.434	0.175	0.939	1.673	1.294	1.004	1.586	0.5
	GPT-4o	0.673	0.711	0.673	0.679	0.477	0.367	0.449	0.67	0.624	0.986	0.793
	GPT-5	0.796	0.812	0.796	0.798	0.657	0.204	0.204	0.452	0.435	0.687	0.894
	Qwen-VL-Max	0.367	0.727	0.367	0.432	0.144	0.776	1.061	1.03	0.857	1.355	0.513
Transverse colon	Gemini-2.5-Pro	0.549	0.72	0.549	0.573	0.394	0.471	0.51	0.714	0.621	0.621	0.803
	Grok-4	0.333	0.527	0.333	0.368	0.12	0.804	1.078	1.038	0.893	0.893	0.612
	GPT-4o	0.647	0.71	0.647	0.665	0.504	0.373	0.412	0.642	0.604	0.604	0.839
	GPT-5	0.784	0.818	0.784	0.796	0.688	0.216	0.216	0.464	0.454	0.454	0.9
	Qwen-VL-Max	0.392	0.543	0.392	0.431	0.155	0.725	0.961	0.98	0.956	0.956	0.495
Descending colon	Gemini-2.5-Pro	0.63	0.723	0.63	0.628	0.503	0.435	0.565	0.752	0.74	0.587	0.738
	Grok-4	0.413	0.432	0.413	0.416	0.211	0.739	1.087	1.043	1.034	0.82	0.518
	GPT-4o	0.63	0.626	0.63	0.615	0.491	0.435	0.565	0.752	0.72	0.571	0.777
	GPT-5	0.696	0.732	0.696	0.689	0.583	0.326	0.37	0.608	0.598	0.474	0.842
	Qwen-VL-Max	0.565	0.532	0.565	0.524	0.408	0.5	0.63	0.794	0.791	0.628	0.689
Sigmoid colon	Gemini-2.5-Pro	0.667	0.715	0.667	0.682	0.532	0.333	0.333	0.577	0.556	0.313	0.828
	Grok-4	0.689	0.696	0.689	0.683	0.57	0.311	0.311	0.558	0.558	0.314	0.855
	GPT-4o	0.556	0.571	0.556	0.541	0.378	0.489	0.578	0.76	0.739	0.416	0.686
	GPT-5	0.778	0.796	0.778	0.783	0.688	0.222	0.222	0.471	0.452	0.254	0.891
	Qwen-VL-Max	0.467	0.653	0.467	0.434	0.222	0.556	0.6	0.775	0.748	0.421	0.63
Rectum	Gemini-2.5-Pro	0.489	0.5	0.489	0.491	0.253	0.689	1.133	1.065	1.062	0.724	0.332
	Grok-4	0.356	0.387	0.356	0.35	0.125	0.644	0.644	0.803	0.788	0.537	0.665
	GPT-4o	0.444	0.502	0.444	0.453	0.238	0.622	0.756	0.869	0.865	0.59	0.606
	GPT-5	0.6	0.611	0.6	0.594	0.433	0.422	0.467	0.683	0.665	0.454	0.752
	Qwen-VL-Max	0.356	0.352	0.356	0.348	0.06	0.711	0.889	0.943	0.926	0.631	0.403

¹Pearson correlation coefficient. MAE: Mean absolute error; MSE: Mean squared error; RMSE: Root mean squared error; CV: Coefficient of variation; SD: Standard deviation.