Performance of rapid influenza H1N1 diagnostic tests: a meta-analysis

Abstract

Background: Following the outbreaks of 2009 pandemic H1N1 infection, rapid influenza diagnostic tests have been used to detect H1N1 infection. However, no meta-analysis has been undertaken to assess the diagnostic accuracy when this manuscript was drafted.

Methods: The literature was systematically searched to identify studies that reported the performance of rapid tests. Random effects meta-analyses were conducted to summarize the overall performance.

Results: Seventeen studies were selected with 1879 cases and 3477 non-cases. The overall sensitivity and specificity estimates of the rapid tests were 0·51 (95%CI: 0·41, 0·60) and 0·98 (95%CI: 0·94, 0·99). Studies reported heterogeneous sensitivity estimates, ranging from 0·11 to 0·88. If the prevalence was 30%, the overall positive and negative predictive values were 0·94 (95%CI: 0·85, 0·98) and 0·82 (95%CI: 0·79, 0·85). The overall specificities from different manufacturers were comparable, while there were some differences for the overall sensitivity estimates. BinaxNOW had a lower overall sensitivity of 0·39 (95%CI: 0·24, 0·57) compared with all the others (P-value <0·001), whereas QuickVue had a higher overall sensitivity of 0·57 (95%CI: 0·50, 0·63) compared with all the others (P-value = 0·005).

Conclusions: Rapid tests have high specificity but low sensitivity and thus limited usefulness.

Figure 1

Forest plot of sensitivity estimates and 95% confidence intervals (CI). Point estimates of sensitivity from each study are shown as solid squares. Solid lines represent the 95% CIs. Squares are proportional to weights based on the random effects model. The pooled estimate and 95% CI is denoted by the diamond at the bottom. Se, sensitivity; TP, true positives; FN, false negatives.

Figure 2

Forest plot of specificity estimates and 95% confidence intervals (CI). Point estimates of sensitivity from each study are shown as solid squares. Solid lines represent the 95% CIs. Squares are proportional to weights based on the random effects model. The pooled estimate and 95% CI is denoted by the diamond at the bottom. Sp, specificity; TN, true negatives; FP, false positives.

Figure 3

The summary receiver operating characteristic plot (panel A) and the overall PPV and NPV plot (panel B) based on the bivariate random effects model. In panel A, each open circle represents a study in the meta‐analysis with both sensitivity and specificity estimates of a rapid test; dotted lines represent those studies with only a sensitivity estimate of a rapid test; the solid circle represents the overall summary point; blue colored solid and dashed contour curves denote the boundaries of the 95% confidence region of the summary point and the 95% prediction region, respectively; black solid lines represent the summary receiver operating characteristic curve. In panel B, solid and dashed lines denote the estimate and 95% confidence interval; PPV, positive predictive value; NPV, negative predictive value.