The protein-to-creatinine ratio for the prediction of significant proteinuria in patients at risk for preeclampsia: a meta-analysis.

To investigate the diagnostic accuracy of the protein-to-creatinine ratio from random urine collections to confirm the presence of proteinuria in women being evaluated for preeclampsia.Eligible studies, published between January 1966 and April 2010, were retrieved through general bibliographic databases. Accuracy of the protein-to-creatinine ratio was estimated compared with a 24- hour urine collection. Pooled estimates of diagnostic measures were calculated. A random-effects bivariate model was employed.Twenty-four trials with 3,186 aggregate participants met inclusion criteria. Pooled sensitivities and specificities were 91.0% (95%CI 87.0 - 93.9) and 86.3% (95% CI 78.4 - 91.7) respectively. Pooled positive likelihood ratio was 6.7 (95% CI 4.1, 10.9) and pooled negative likelihood ratio 0.10 (95%CI 0.07, 0.16). Meta-regression analysis found that test accuracy was not affected by any of the co-variables explored.A random urine protein-to-creatinine ratio provides useful evidence to rule out the presence of significant proteinuria in patients at risk for preeclampsia. It appears that a cut-off value of > 0.30 is associated with the best accuracy.The protein-to-creatinine ratio from a random urine sample provides useful evidence to rule out the presence of significant proteinuria in patients at risk for preeclampsia.