Measure | Antenatal phase | Postnatal phase | ||
---|---|---|---|---|
Case-finding questions* n = 126† | Question about need for help‡ n = 52 | Case-finding questions* n = 94† | Question about need for help‡ n = 45 | |
True positive, no. | 17 | 10 | 18 | 7 |
False negative, no. | 0 | 7 | 0 | 11 |
True negative, no. | 74 | 32 | 49 | 27 |
False positive, no. | 35 | 3 | 27 | 0 |
Sensitivity, % (95% CI) | 100 (77–100) | 58 (38–76) | 100 (78–100) | 39 (18–64) |
Specificity, % (95% CI) | 68 (58–76) | 91 (78–97) | 65 (53–75) | 100 (85–100) |
Positive likelihood ratio (95% CI) | 3.03 (2.28–4.02) | 6.86 (2.16–21.7) | 2.73 (2.0–3.74) | 21.4 (1.3–354.2) |
Negative likelihood ratio (95% CI) | 0.041 (0.003–0.63) | 0.45 (0.25–0.80) | 0.042 (0.003–0.65) | 0.62 (0.43–0.90) |
Note: CI = confidence interval.
↵* There were no missing responses to the case-finding questions. A positive response to either of the two questions was considered a positive screen.
↵† This is the number of women who also completed the telephone interview. A total of 152 women (antenatal phase) and 97 women (postnatal phase) answered the case-finding questions.
↵‡ Responses to an additional question about the need for help were elicited only from participants with a positive response to either of the case-finding questions.