We evaluated pooled effect sizes for 23 clinical characteristics (age, sex, diabetes, stage CKD3, stage CKD4, stage CKD5, albumin, hemoglobin, serum creatinine, estimated glomerular filtration rate, complement C3, complement C4, urinary protein level, urinary protein ≥ 1.5 g/d, nephrotic range proteinuria, hematuria, monoclonal, biclonal, kappa-chain value, lambda-chain value, abnormal free light-chain ratio, bone marrow puncture rate, and abnormal bone marrow outcome rate). This evidence concerns the gene C4A and diabetes mellitus.