He Y, et al. - Researchers analyzed 37 studies from 31 original studies, to determine as well as to compare the predictive worth of neutrophil gelatinase-associated lipocalin (NGAL) and cystatin C in the early diagnosis of contrast-induced nephropathy (CIN). The relevant studies were identified from PubMed, EMBASE and Cochrane Library databases via a search until November 10, 2019. Experts used the Quality Assessment of Diagnostic Accuracy Studies 2 tool to evaluate the methodological quality of the included studies. They found that serum cystatin C outperformed serum/urine NGAL; a similar diagnostic performance of serum and urine NGAL was noted. The ability of both NGAL and cystatin C to serve as early diagnostic indicators of CIN was shown, while cystatin C vs NGAL may perform better.