Table 2 Expert panel characteristics for included studies. Numbers are presented as a total number accompanied by the percentage of the total number of included studies, i.e., k (%), for categorical variables, or median with accompanying interquartile range, i.e., median [p25; p75], for continuous variables

Number of experts involved in the study

3 [2; 4]

54 (17%)

Number of experts included per panel

3 [2; 3]

40 (13%)

 2 or fewer

25%

 3–4

48%

 5–9

11%

 10 + 

2.4%

All study participants assessed by the same panel (i.e., same experts)

241 (76%)

37 (12%)

Expertise of experts within the panel

44 (13%)

 Same expertise

201 (63%)

 Mixed expertise

73 (23%)

Index test/model incorporated in the information provided to the panel

58 (18%)

18 (6%)

Participants were assessed for their target condition status by an expert panel before the identified study (e.g., in a databank or previous study)

13 (4%)

4 (1%)

Alternative reference standard other than expert panel used in some study participants (differential verification)

46 (14%)

20 (6%)

Assessment of level of uncertainty about presence or absence of target condition

16 (5%)

0 (0%)