Another study by Liu discovered that the diagnosis accuracy of IGFBP7 and TIMP-2 in diagnosing ARF in its early stage had a sensitivity of 83% (95% CI 0.75–0.89), specificity of 72% (95% CI 0.56–0.84), and summary receiver operating characteristic (SROC) of 0.86 (95% CI 0.82–0.88), while on stage 2 of GgGA according to the 2012 KDIGO classification, it had a sensitivity of 0.92 (95% CI 0.81–0.96), specificity of 0.63 (95% CI 0.49–0.74), and SROC of 0.88 (95% CI 0.85–0.91). Here, TIMP2 is linked to acute kidney injury.