Table 4: Factors associated with positive bacterial culture in antenatal women.

(a) Relationship between dipstick positive urine, microscopy positive, and culture positive in antenatal women.


Among culture positives (N = 40) Among culture negatives (N = 110)

Dipstick positive 31 (77.5%) 18 (16.3%)
Urine microscopy Positive 27(67.5%) 13(11.8%)

(b) Sensitivity, specificity, and predictive values of urine dipstick tests in diagnosis.


Dipstick test UTI positive culture Negative culture Total

Positive 31 18 49
Negative 9 92 101
Total 40 110 150

Sensitivity = 31/31+9×100 = 77.5%
Specificity = 92/92 + 18×100 = 83.6%
Positive predictive value = 31/31 + 18×100 = 63.3%
Negative predictive value = 92/92 + 9×100 = 91.1%

(c) Sensitivity specificity and predictive values of urine microscopy test in diagnosing UTI in antenatal women.


Urine microscopy UTI positive Urine culture No UTI negative urine culture Totals

Positive 27 13 40
Negative 13 97 110
Total 40 110 150

Sensitivity = 27/27 + 13×100 = 67.5%
Specificity = 97/97 + 13×100 = 88.2%
Positive predictive value = 27/27 + 13×100 = 67.5%
Negative predictive value = 97/97 + 13×100 = 88.2%