Multivariate Models, Point Scores, and Symptom Combinations Reported by Included Studies
| Study | Model | Accuracy |
|---|---|---|
| AUC = area under the receiver operating characteristic curve; CI = confidence interval; LR+ = positive likelihood ratio, LR− = negative likelihood ratio; NPV = negative predictive value; OR = odds ratio; PPV = positive predictive value. | ||
| Govaert et al,13 1998 | Variable: OR | Not reported |
| Cough: 5.25 | ||
| Fever: 2.18 | ||
| Vaccinated: 0.56 | ||
| Constant: 0.041 | ||
| Govaert et al,13 1998 | Symptom count (fever, cough, acute onset, malaise, rigors or chills, myalgia, headache, sore throat) | Not reported other than data shown |
| Score (n): % influenza | ||
| 0 (1,155): 3.2 | ||
| 1–2 (145): 6.2 | ||
| ≤3 (491): 15 | ||
| Carrat et al,23 1999 | Variable: OR | Goodness of fit: P=.98 |
| All influenza | ||
| Temperature >38.2°C: 2.45 | ||
| Rhinorrhea: 1.83 | ||
| Temperature >38.9°C, respiratory signs, and stiffness or myalgia Temperature >37.7°C and cough or sore throat Any 3 of temperature >37.7°C, cough, chills, moderate/severe fatigue, cervical or dorsal pain, pharyngitis, and another case at patient’s home | PPV: 40%; NPV: 80% PPV: 30%; NPV: 86% PPV: 27%; NPV: 91% | |
| Monto et al,11 2000 | Variable: OR (95% CI) | Accuracy of multivariate model not reported |
| Fever >37.7°C: 3.26 (2.75–3.87) | ||
| Cough: 2.85 (2.21–3.68) | ||
| Nasal congestion: 1.98 (1.54–2.54) | ||
| Age ≥55 y: 1.60 (1.18–2.16) | ||
| Weakness: 1.54 (1.07–2.22) | ||
| Onset >36 hr: 1.53 (1.24–1.90) | ||
| Loss of appetite: 1.43 (1.10–1.86) | ||
| Sex, male: 1.27 (1.08–1.50) | ||
| Sore throat: 0.72 (0.57–0.91) | ||
| Boivin et al,12 2000 | Variable: OR (95% CI) | PPV: 87%; NPV: 39% |
| Cough: 6.68 (1.4–34.1) | ||
| Temperature ≥38°C: 3.06 (1.35–8.02) | ||
| van Elden et al,10 2001 | Period of increased influenza activity, cough, headache at onset, feverishness at onset, and not vaccinated During an outbreak, abrupt onset (<5 days), temperature >38°C, and at least 1 of cough, coryza, headache, retrosternal pain, or myalgia At least 4 of sudden onset, contact with influenza, fever, cough, chills, malaise, myalgia, or hyperemic mucous membranes of the nose and throat (≥6 required if not in outbreak) | PPV: 75%; NPV: 80% PPV: 52% PPV: 54%; NPV: 85% |
| Senn et al,7 2005 | Week of consultation (49–50 vs ≥51), duration of symptoms (≤48 hr vs >48 hr), temperature >37.8°C, and cough | AUC=0.74 Sensitivity: 80%; specificity: 59% LR+: 1.95; LR−: 0.34 PPV: 67%; NPV: 73% LR+/LR−=5.7 |
| Ohmit and Monto,24 2006 | Study 1, zanamivir—variable: OR (95% CI) | Accuracy not reported; only variables significant at P <.05 level included |
| Age, y: 1.11 (1.00–1.23) | ||
| Fever: 2.67 (1.66–4.30) | ||
| Cough: 5.19 (2.66–10.10) | ||
| Myalgia: 0.61 (0.38–0.99) | ||
| Sore throat: 0.41 (0.24–0.70) | ||
| Study 2, oseltamivir (age 1–4 y)—variable: OR (95% CI) | ||
| Myalgia: 2.32 (1.22–4.39) | ||
| Study 2, oseltamivir (age 5–12 y)—variable: OR (95% CI) | ||
| Cough: 10.94 (2.90–40.80) | ||
| Headache: 2.24 (1.15–4.37) | ||