“…All of them have been classified into two categories based on the number of analytes. Forty-nine publications involved analyzing one drug (n = 1) and the remaining 23 involved analyzing multiple drugs/metabolites (n ≥ 2) are summarized in Table 1 [4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52] and Table 2 [53,54,55,56,57,58,59,60,61,62,<...>…”