“…Twelve studies examined CKD [ 22 - 33 ], 15 studies examined nephrolithiasis [ 13 , 34 - 47 ], and two studies examined both CKD and nephrolithiasis [ 48 , 49 ] (Table 1 ). Nineteen cross-sectional studies [ 13 , 22 , 25 , 27 , 29 , 30 , 32 , 34 - 38 , 40 - 42 , 46 - 49 ], one case–control study [ 26 ], and nine cohort studies [ 23 , 24 , 28 , 31 , 33 , 39 , 43 - 45 ] were identified. Six of the nine cohort studies included relevant outcome data only at baseline and so were treated as cross-sectional studies [ 24 , 31 , 33 , 43 - 45 ].…”