Table 2

GRADE assessment of evidence quality of urine dipstick (nitrites) accuracy (index test) to detect asymptomatic bacteriuria (reference standard: urine culture) in pregnancy8

(presence or absence of bacteriuria)
No of studies
(No of patients)
Features that may affect evidence quality*Quality of evidence‡
Risk of biasIndirectnessInconsistencyImprecisionPublication bias†
True positives
(patients with asymptomatic bacteriuria)
21 cross-sectional studies
(699 patients)
Sensitivity 0.56
(95% CI 0.42 to 0.69)
Very low
False negatives
(patients incorrectly classified as not having asymptomatic bacteriuria)
True negatives
(patients without asymptomatic bacteriuria)
21 cross-sectional studies
(8560 patients)
Specificity 0.99
(95% CI 0.98 to 0.99)
Serious§Serious¶Not seriousNot serious⨁⨁◯◯
False positives
(patients incorrectly classified as having asymptomatic bacteriuria)
  • *As specified in table 1.

  • †Domain was not assessed (see text for justification).

  • ‡See figure 1 for graphic display of quality of evidence.

  • §57% of included studies of low and moderate quality14 (in the cited reference the detail quality assessment appears in appendix 5).

  • ¶54% of included studies were assessed as ‘high’ or ‘unclear’ concern over applicability.

  • **Visible variability between studies on the forest plot.

  • ††Noticeable imprecision, wide CIs.