Table 1.

Characteristics of included studies.

Study ID	Country	Setting	Population	N (% Male)	Mean Age	BMI (SD)	Target Conditions	DM	AST (U/L)	ALT (U/L)
Daniels 2019 [29]	Australia, UK, Japan	Secondary and tertiary care	Biopsy-confirmed NAFLD	239 (56%)	52.2	33.6 (7.7)	F ≥ 2; F ≥ 3; F4	37%	49.6 (34.4) *	72.2 (54.6) *
Boyle 2019 [28]	7 European countries	Tertiary care	Suspected NAFLD	449 (59%)	52.0	32.6 (6.8)	F ≥ 3; NASH + F ≥ 2; NASH + F4	48%	47.0 (26.0)	69.0 (41.0)
Huber 2019 [44]	Germany	Secondary or tertiary care	Biopsy-confirmed NAFLD	27 (66%)	41.0 †	30.8 (5.1)	F ≥ 2; F ≥ 3	27%	NR	NR
Luo 2018 Discovery [43]	USA	Secondary or tertiary care	Suspected or biopsy-confirmed NAFLD	164 (32%)	53.3	NR	F ≥ 2; F ≥ 3	NR	46.8 (21.3) *	59.8 (38.1) *
Luo 2018 Validation [23]	USA	Secondary or tertiary care	Biopsy-confirmed NAFLD	41 (32%)	50.1	NR	F ≥ 2; F ≥ 3	37%	71.3 (50.6) *	98.3 (57.5) *
Nielsen, Leeming 2021 [30]	USA, Australia, Belgium, France, Germany, Hong Kong, Italy, Poland, Spain, UK	Secondary or tertiary care	Biopsy-confirmed NAFLD	517 (52%)	55.2 †	32.7 †	F ≥ 2; F ≥ 3; NASH	40%	34.8 †	47.1 †
Bril 2019 [41]	USA	Primary and tertiary care	Suspected NAFLD	125 (87%)	58.7	34.4 (4.6)	F ≥ 2; F ≥ 3	100%	40.4 (23.1)	53.6 (35.6)
Knöchel 2021 [42]	Sweden	Secondary or tertiary care	Biopsy-confirmed NAFLD	56 (71%)	61.0	29.1 (4.7)	F ≥ 2; F ≥ 3	NR	NR	NR
Erhardtsen 2021 [45]	UK and Germany	Secondary and tertiary care	Biopsy-confirmed NAFLD	215 (52%)	56.0	33 †	F ≥ 2; F ≥ 3; NASH + F ≥ 2	47%	48.5 †	64.0 †

* not documented for all patients; † = median, not mean; NAFLD = non-alcoholic fatty liver disease, NASH = non-alcoholic steatohepatitis, AST = aspartate aminotransferase, ALT = alanine aminotransferase, BMI = body mass index, NR = not reported, SD = standard deviation, DM = diabetes mellitus.