Criteria 
Score 
The number of subjects 
NA 
0 
0<n<50 
1 
50 ≤ n<100 
2 
100 ≤ n<150 
3 
150 ≤ n 
4 
Age (year old) 
NA 
0 
Welch’s tvalue of age range ≥ 2.77* 
1 
Welch’s tvalue of age range<2.77* 
2 
MMSE score 
NA 
0 
Welch’s tvalue of MMSE range<24.15† 
1 
Welch’s tvalue of MMSE range ≥ 24.15† 
2 
Statistical significance (pvalue) 
NA 
0 
0.01<pvalue ≤ 0.05 
1 
0.001<pvalue ≤ 0.01 
2 
0<pvalue ≤ 0.001 
3 
Maximum metascore 
15 

Metascore of each biomarker was calculated by the sum of assigned scores
in each criterion. Therefore, maximum metascore per a single article can be
4+4+2+2+3=15 (the number of subjects for control [4] and AD [4]+age [2]+MMSE
score [2]+statistical significance [3]). If one biomarker was reported by multiple
articles, the metascores evaluated in each article were then added. *2.77 is mean
of Welch’s tvalue for age range. †24.15 is mean of Welch’s tvalue for MMSE
range. 
Table 2: Criteria of metascoring system for BBs of AD. 