Table 4. Frequency (%) and validity of historical factors reported by mothers, clinical signs observed and classification of illness,a and Kappa statistics for agreement between assessments by CHWs and by physicians (gold standard) in Mirzapur, Bangladesh, 2005–2006.
| Historical factor or clinical sign | Frequency |
TN | FN | FP | TP | Sensitivity |
Specificity |
PPV |
NPV |
Κ | P-value | |||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| % | SE | % | SE | % | SE | % | SE | % | SE | |||||||
| Historical factor | ||||||||||||||||
| Yellow body colour | 3.8 | 1.0 | 379 | 15 | 1 | 0 | 0.0 | 0.0 | 99.7 | 0.3 | 0.0 | 0.0 | 96.2 | 1.0 | 0.00 | 0.58 |
| Mother feels baby is hot | 1.3 | 0.6 | 389 | 4 | 1 | 1 | 20.0 | 17.9 | 99.7 | 0.3 | 50.0 | 35.4 | 99.0 | 0.5 | 0.28 | 0.00 |
| Any skin problems | 1.8 | 0.7 | 387 | 6 | 1 | 1 | 14.3 | 13.2 | 99.7 | 0.3 | 50.0 | 35.4 | 98.5 | 0.6 | 0.22 | 0.00 |
| Umbilical pus or redness, or foul smell | 0.8 | 0.4 | 391 | 3 | 1 | 0 | 0.0 | 0.0 | 99.7 | 0.3 | 0.0 | 0.0 | 99.2 | 0.4 | 0.00 | 0.53 |
| Clinical sign | ||||||||||||||||
| Respiratory rate ≥ 70 bpm | 1.0 | 0.5 | 390 | 3 | 1 | 1 | 25.0 | 21.7 | 99.7 | 0.3 | 50.0 | 35.4 | 99.2 | 0.4 | 0.33 | 0.00 |
| Respiratory rate 60–69 bpm | 7.1 | 1.3 | 361 | 26 | 6 | 2 | 7.1 | 4.9 | 98.4 | 0.7 | 25.0 | 15.3 | 93.3 | 1.3 | 0.08 | 0.02 |
| Severe fever: temperature > 101 °F (38.3 °C) | 0.5 | 0.4 | 393 | 1 | 0 | 1 | 50.0 | 35.4 | 100.0 | 0.0 | 100.0 | 0.0 | 99.7 | 0.3 | 0.67 | 0.00 |
| Moderate fever: temperature 100.0–101 °F (37.8–38.3 °C) | 1.5 | 0.6 | 387 | 4 | 2 | 2 | 33.3 | 19.2 | 99.5 | 0.4 | 50.0 | 25.0 | 99.0 | 0.5 | 0.39 | 0.00 |
| Severe hypothermia: temperature < 95.5 °F (35.3 °C) | 0.8 | 0.4 | 389 | 0 | 3 | 3 | 100.0 | 0.0 | 99.2 | 0.4 | 50.0 | 20.4 | 100.0 | 0.0 | 0.66 | 0.00 |
| Moderate hypothermia: temperature 95.5–97.5 °F (35.3–36.4 °C) | 2.5 | 0.8 | 375 | 8 | 10 | 2 | 20.0 | 12.6 | 97.4 | 0.8 | 16.7 | 10.8 | 97.9 | 0.7 | 0.16 | 0.00 |
| Weak, abnormal or absent cry | 0.5 | 0.4 | 391 | 2 | 2 | 0 | 0.0 | 0.0 | 99.5 | 0.4 | 0.0 | 0.0 | 99.5 | 0.4 | –0.01 | 0.54 |
| Lethargic or less than normal movement | 1.0 | 0.5 | 388 | 3 | 3 | 1 | 25.0 | 21.7 | 99.2 | 0.4 | 25.0 | 21.7 | 99.2 | 0.4 | 0.24 | 0.00 |
| Unable to feed or suck, or not attachedb | 0.5 | 0.4 | 389 | 0 | 4 | 2 | 100.0 | 0.0 | 99.0 | 0.5 | 33.3 | 19.2 | 100.0 | 0.0 | 0.50 | 0.00 |
| Skin pustules | 2.0 | 0.7 | 381 | 6 | 6 | 2 | 25.0 | 15.3 | 98.4 | 0.6 | 25.0 | 15.3 | 98.4 | 0.6 | 0.23 | 0.00 |
| Umbilicus discharging pus | 2.0 | 0.7 | 384 | 5 | 3 | 3 | 37.5 | 17.1 | 99.2 | 0.4 | 50.0 | 20.4 | 98.7 | 0.6 | 0.42 | 0.00 |
| Umbilical redness not extending to skin | 0.8 | 0.4 | 388 | 3 | 4 | 0 | 0.0 | 0.0 | 99.0 | 0.5 | 0.0 | 0.0 | 99.2 | 0.4 | –0.01 | 0.57 |
| Jaundiced palms and soles after the day of birth | 3.5 | 0.9 | 380 | 11 | 1 | 3 | 21.4 | 11.0 | 99.7 | 0.3 | 75.0 | 21.7 | 97.2 | 0.8 | 0.32 | 0.00 |
| Ulcer or white patches inside the oral cavity | 0.3 | 0.3 | 391 | 0 | 3 | 1 | 100.0 | 0.0 | 99.2 | 0.4 | 25.0 | 21.7 | 100.0 | 0.0 | 0.40 | 0.00 |
| Classification of illness | ||||||||||||||||
| Very severe disease | 2.8 | 0.8 | 378 | 3 | 6 | 8 | 72.7 | 13.4 | 98.4 | 0.6 | 57.1 | 13.2 | 99.2 | 0.5 | 0.63 | 0.00 |
| Possible very severe disease | 6.8 | 1.3 | 355 | 18 | 13 | 9 | 33.3 | 9.1 | 96.5 | 1.0 | 40.9 | 10.5 | 95.2 | 1.1 | 0.33 | 0.00 |
| Local infection | 4.3 | 1.0 | 369 | 11 | 9 | 6 | 35.3 | 11.6 | 97.6 | 0.8 | 40.0 | 12.6 | 97.1 | 0.9 | 0.35 | 0.00 |
| Oral thrush | 0.3 | 0.3 | 391 | 0 | 3 | 1 | 100.0 | 0.0 | 99.2 | 0.4 | 25.0 | 21.7 | 100.0 | 0.0 | 0.40 | 0.00 |
bpm, breaths per minute; FN, false negative; FP, false positive; Κ, Kappa statistics; TN, true negative; TP, true positive; NPV, negative predictive value; PPV, positive predictive value; SE, standard error; VSD, very severe disease. a Validity (sensitivity, specificity, positive predictive value, negative predictive value) was not estimated for 5 historical factors, 12 clinical signs and 7 illness classifications whose frequency was 0%. The 5 historical factors were: no breathing immediately after birth; unconscious; persistent vomiting; blood in stool*; and vomiting everything. The 12 clinical signs were: convulsion; severe chest in-drawing; bulging fontanelle; unconsciousness; many or severe skin pustules; umbilical redness extending to abdominal skin; unable to drink or drinks poorly*; lethargic or unconscious*; slow skin pinch retraction (> 2 seconds)*; drinks eagerly*; restless or irritable*; and skin pinch retraction time > 2 seconds*. The 7 illness classifications were: perinatal asphyxia; significant jaundice on the first day of life; possible gonococcal eye infection; diarrhoea with blood; diarrhoea with severe dehydration; diarrhoea with some dehydration; and diarrhoea without dehydration. Since the classification of “fast breathing” is based on one clinical sign (“respiratory rate 60–69 per minute”) that is presented under “observation of individual signs”, validity estimates of the classification are not repeated. In addition, validity was not estimated for 7 historical factors and 2 clinical signs whose frequency was > 0% but for which no false positive or true positive results were obtained. The 7 historical factors and their frequencies (in parentheses) were: no cry immediately after birth (0.5%); convulsion (0.3%); difficult breathing (1.3%); mother feels baby is cold (1.0%); weak, abnormal or absent cry (0.3%); baby lethargic or less active than normal (0.5%); and feeding problem (2.5%). The 2 clinical signs were jaundice anywhere in the body within 24 hours after birth (0.3%) and eye discharging pus (0.3%). * Assessed only if a mother reported the neonate had diarrhoea. b Assessed by female physicians and nurses.