TABLE 2.

Summary of the 871 Reports Based on Image Type, Average Text Length, and Patients’ Age and Gender Across the Four Healthcare Systems

System	Image Type	N in Dataset	Average Text Length	Average Age	Female %
Kaiser Permanente of Washington	X-Ray	102	132 ± 34	70.35 ± 13.84	0.60
	MR	115	267 ± 106	58.90 ± 14.35	0.49
	Total	217	203 ± 105	64.28 ± 15.20	0.54
Kaiser Permanente of Northern California	X-Ray	104	143 ± 38	67.51 ± 16.82	0.61
	MR	114	270 ± 95	57.1 ± 14.96	0.53
	Total	218	210 ± 97	62.06 ± 16.68	0.56
Henry Ford Health System	X-Ray	103	121 ± 57	67.15 ± 16.04	0.72
	MR	115	268 ± 152	58.95 ± 15.77	0.5
	Total	218	199 ± 137	62.96 ± 16.44	0.61
Mayo Clinic Health System	X-Ray	103	141 ± 39	69.35 ± 16.15	0.61
	MR	115	222 ± 104	55.13 ± 15.44	0.58
	Total	218	184 ± 90	61.85 ± 17.28	0.60
All	X-Ray	413	134 ± 44	68.58 ± 15.76	0.63
	MR	458	257 ± 118	57.52 ± 15.17	0.52
	Total	871	199 ± 109	62.79 ± 16.42	0.58

We calculated the average text length for the finding and impression sections in each report, the average age of patients, and the proportion of female patients for each healthcare system and each type of report. For average text length, we calculated the average text length for both the finding and impression sections, since these sections were required for our pipeline. For both average text length and age, we included standard deviation.