TABLE 5.

Mean cohort size and model performance statistics for all publications

	Training size (no patients)	Testing size (no. patients)	CBCT MAE (HU)	sCT MAE (HU)	% MAE improvement
All studies	47.74 ± 47.11	11.02 ± 7.90	–	46.83 ± 22.23	–
All studies*	51.27 ± 44.27	11.77 ± 8.77	114.66 ± 75.84	45.13 ± 22.01	54.60 ± 17.90
Pelvis*	62.63 ± 43.20	10.88 ± 6.11	117.47 ± 93.73	41.58 ± 22.73	57.97 ± 19.68
HN*	45.63 ± 39.38	12.13 ± 10.17	106.59 ± 84.63	36.13 ± 21.76	58.67 ± 10.75
Thorax*	59.00 ± 56.18	14.17 ± 9.46	134.52 ± 49.45	54.12 ± 20.47	57.54 ± 12.65
Abdomen*	20.33 ± 7.36	4.67 ± 2.62	98.34 ± 30.35	51.78 ± 5.59	41.33 ± 19.51

Note: * indicates studies which reported CBCT and sCT MAE values.

Abbreviations: CBCT, cone‐beam CT; HN, head and neck; MAE, mean absolute error; sCT, synthetic CT.