Table 1.
Utility of specific cough pointers in differentiating specific coughs from non-specific coughs in children with chronic cough.
| Pointer | Reference | Design | Setting | Population | Reference standard | Sensitivity | Specificity | PPV | NPV | PLR | NLR |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Wet cough | Marchant et al. (8) | Prospective cohort | Single tertiary hospital in Australia | 100 children with CC without known lung or other serious medical conditions (median age 2.8 years) | Specific cough (all causes) | 96% | 26% | 74% | 73% | 1.29 | NR |
| Chang et al. (9) | Prospective cohort | Multi-centers in Australia | 326 children with CC without a previous diagnosis confirmed by objective tests (asthma, CF, or BE) (mean age 3.3 years) | Specific cough (all causes) | 65% (60–71%) | 98% (85–100%) | 99% (97–100%) | 28% (21–37%) | 26.15 (3.77–181.48) | 0.36 (0.30–0.42) | |
| Wet cough not resolved after 4 weeks | Chang et al. (9) | as above | as above | as above | Specific cough (all causes) | 3% (2–7%) | 100% (89–100%) | 100% (65–100%) | 13% (9–16%) | Infinity | 0.97 (0.94–0.99) |
| Wheeze or reversible airway obstruction | Chang et al. (9) | as above | as above | as above | Specific cough (all causes) | 21 % (17–26%) | 100% (89–100%) | 100% (92–100%) | 15% (11–20%) | Infinity | 0.79 (0.74–0.84) |
| Exertional dyspnea | Marchant et al. (8) | as above | as above | as above | Specific cough (all causes) | 38% | 65% | 70% | 32% | 1.06 | NR |
| Chang et al. (9) | as above | as above | as above | Specific cough (all causes) | 3% (2–6%) | 100% (90–100%) | 100% (63–100%) | 10% (10–20%) | Infinity | 1.0 (0.9– 1.0) | |
| Chronic dyspnea | Marchant et al. (8) | as above | as above | as above | Specific cough (all causes) | 7% | 97% | 83% | 32% | 2.25 | NR |
| Recurrent pneumonia | Marchant et al. (8) | as above | as above | as above | Specific cough (all causes) | 7% | 94% | 71% | 31% | 1.12 | NR |
| Chang et al. (9) | as above | as above | as above | Specific cough (all causes) | 3% (2–7%) | 100% (89–100%) | 100% (66–100%) | 12% (9–17%) | Infinity | 0.96 (0.94–0.99) | |
| Hemoptysis | Marchant et al. (8) | as above | as above | as above | Specific cough (all causes) | 7% | 97% | 83% | 32% | 2.25 | NR |
| Cough associated swallowing | Marchant et al. (8) | as above | as above | as above | Specific cough (all causes) | 25% | 71% | 65% | 30% | 0.85 | NR |
| Failure to thrive | Chang et al. (9) | as above | as above | as above | Specific cough (all causes) | 0% (0–2%) | 100% (89–100%) | 100% (5–100% | 13% (9–17%) | Infinity | 1.0 (0.99–1.00) |
| Feeding difficulties | Chang et al. (9) | as above | as above | as above | Specific cough (all causes) | 6% (3–9%) | 100% (89–100%) | 100% (76–100%) | 13% (9–17%) | Infinity | 0.94 (0.92–0.97) |
| Chest pain | Chang et al. (9) | as above | as above | as above | Specific cough (all causes) | 0% (0–2%) | 100% (89–100%) | 100% (5–100%) | 13% (9–17%) | Infinity | 1.0 (0.99–1.00) |
| Any cough pointer | Chang et al. (9) | as above | as above | as above | Specific cough (all causes) | 100% (98–100%) | 95% (82–99%) | 99% (97–100%) | 100% (89–100%) | 20 (5.18–77.21) | 0 (0– 0.03) |
CC, chronic cough; PPV, positive predictive value; NPV, negative predictive value; PLR, positive likelihood ratio; NLR, negative likelihood ratio; NR, not reported; FBA, foreign body aspiration.