Table 5.
Symptom | Age, years | Minor febrile infections, % | Meningococcal disease, adjusted %a | Sensitivity, % (95% CI) | Specificity, % (95% CI) | Positive likelihood ratio (95% CI) | Negative likelihood ratio (95% CI) |
---|---|---|---|---|---|---|---|
Classic meningeal features | |||||||
Photophobia | <1 | 2.4 | 25.1 | 25.1 (15.1 to 35.1) | 97.6 (92.8 to 102.3) | 10.3 (1.4 to 74.2) | 0.8 (0.7 to 0.9) |
1–4 | 2.8 | 25.0 | 25.0 (17.1 to 32.9) | 97.2 (95.0 to 99.4) | 8.9 (3.8 to 20.7) | 0.8 (0.7 to 0.9) | |
5–14 | 5.9 | 26.9 | 26.9 (16.7 to 37.1) | 94.1 (90.4 to 97.8) | 4.6 (2.2 to 9.6) | 0.8 (0.7 to 0.9) | |
Neck pain or stiffness | <1 | 1.2 | 16.3 | 16.3 (7.9 to 24.8) | 98.8 (95.5 to 102.1) | 13.7 (0.8 to 226.3) | 0.8 (0.8 to 0.9) |
1–4 | 2.3 | 29.1 | 29.1 (20.9 to 37.4) | 97.7 (95.6 to 99.7) | 12.4 (5.0 to 30.9) | 0.7 (0.6 to 0.8) | |
5–14 | 11.8 | 47.0 | 47.0 (35.5 to 58.5) | 88.2 (83.1 to 93.3) | 4.0 (2.4 to 6.6) | 0.6 (0.5 to 0.8) | |
Headache | 1–4 | 18.5 | 21.9 | 21.9 (14.4 to 29.3) | 81.5 (76.3 to 86.7) | 1.2 (0.8 to 1.8) | 1.0 (0.9 to 1.1) |
5–14 | 59.5 | 56.7 | 56.7 (45.3 to 68.1) | 40.5 (32.7 to 48.3) | 1.0 (0.8 to 1.2) | 1.1 (0.8 to 1.5) | |
Suggested ‘red flag’ features | |||||||
Leg pain | 1–4 | 3.3 | 31.7 | 31.7 (23.2 to 40.1) | 96.7 (94.3 to 99.1) | 9.6 (4.4 to 20.9) | 0.7 (0.6 to 0.8) |
5–14 | 9.2 | 63.3 | 63.3 (52.1 to 74.4) | 90.8 (86.3 to 95.4) | 6.9 (4.1 to 11.7) | 0.4 (0.3 to 0.5) | |
Cold hands or feet | <1 | 24.4 | 45.0 | 45.0 (33.5 to 56.4) | 75.6 (62.5 to 88.8) | 1.8 (1.0 to 3.3) | 0.7 (0.6 to 1.0) |
1–4 | 20.2 | 47.0 | 47.0 (37.9 to 56.0) | 79.8 (74.4 to 85.2) | 2.3 (1.7 to 3.2) | 0.7 (0.6 to 0.8) | |
5–14 | 13.7 | 35.1 | 35.1 (24.1 to 46.1) | 86.3 (80.8 to 91.7) | 2.6 (1.5 to 4.2) | 0.8 (0.6 to 0.9) | |
Pale colour | <1 | 36.6 | 18.7 | 18.7 (9.8 to 27.7) | 63.4 (48.7 to 78.2) | 0.5 (0.3 to 1.0) | 1.3 (1.0 to 1.7) |
1–4 | 38.0 | 9.6 | 9.6 (4.2 to 14.9) | 62.0 (55.5 to 68.5) | 0.3 (0.1 to 0.5) | 1.5 (1.3 to 1.6) | |
5–14 | 47.7 | 16.4 | 16.4 (7.9 to 24.9) | 52.3 (44.4 to 60.2) | 0.3 (0.2 to 0.6) | 1.6 (1.3 to 1.9) | |
Other features | |||||||
Confusion | 1–4 | 2.3 | 44.2 | 44.2 (35.2 to 53.2) | 97.7 (95.6 to 99.7) | 18.8 (7.7 to 45.8) | 0.6 (0.5 to 0.7) |
5–14 | 1.3 | 49.9 | 49.9 (38.3 to 61.4) | 98.7 (96.9 to 100.5) | 38.1 (9.4 to 154.1) | 0.5 (0.4 to 0.6) | |
Drowsy or very sleepy | <1 | 31.7 | 87.7 | 87.7 (80.2 to 95.3) | 68.3 (54.0 to 82.5) | 2.8 (1.8 to 4.4) | 0.2 (0.1 to 0.3) |
1–4 | 36.2 | 88.7 | 88.7 (83.0 to 94.5) | 63.8 (57.4 to 70.3) | 2.5 (2.0 to 3.0) | 0.2 (0.1 to 0.3) | |
5–14 | 34.0 | 78.2 | 78.2 (68.7 to 87.7) | 66.0 (58.5 to 73.5) | 2.3 (1.8 to 3.0) | 0.3 (0.2 to 0.5) | |
Rash or new spots on skin | <1 | 22.0 | 62.8 | 62.8 (51.7 to 73.9) | 78.0 (65.4 to 90.7) | 2.9 (1.6 to 5.2) | 0.5 (0.3 to 0.7) |
1–4 | 14.1 | 79.9 | 79.9 (72.6 to 87.2) | 85.9 (81.2 to 90.6) | 5.7 (4.0 to 8.0) | 0.2 (0.2 to 0.3) | |
5–14 | 11.8 | 89.0 | 89.0 (81.8 to 96.2) | 88.2 (83.1 to 93.3) | 7.6 (4.9 to 11.8) | 0.1 (0.1 to 0.2) | |
Nausea or vomiting | <1 | 39.0 | 53.4 | 53.4 (41.9 to 64.8) | 61.0 (46.0 to 75.9) | 1.4 (0.9 to 2.1) | 0.8 (0.5 to 1.1) |
1–4 | 35.2 | 76.4 | 76.4 (68.6 to 84.1) | 64.8 (58.4 to 71.2) | 2.2 (1.8 to 2.7) | 0.4 (0.3 to 0.5) | |
5–14 | 36.6 | 86.6 | 86.6 (78.7 to 94.4) | 63.4 (55.8 to 71.0) | 2.4 (1.9 to 3.0) | 0.2 (0.1 to 0.4) | |
Irritable or miserable | <1 | 63.4 | 85.0 | 85.0 (76.8 to 93.2) | 36.6 (21.8 to 51.3) | 1.3 (1.0 to 1.7) | 0.4 (0.2 to 0.8) |
1–4 | 63.8 | 76.4 | 76.4 (68.6 to 84.1) | 36.2 (29.7 to 42.6) | 1.2 (1.0 to 1.4) | 0.7 (0.5 to 0.9) | |
5–14 | 33.3 | 53.8 | 53.8 (42.3 to 65.3) | 66.7 (59.2 to 74.1) | 1.6 (1.2 to 2.2) | 0.7 (0.5 to 0.9) | |
General aching | <1 | 12.2 | 22.4 | 22.4 (12.8 to 32.1) | 87.8 (77.8 to 97.8) | 1.8 (0.7 to 4.6) | 0.9 (0.7 to 1.0) |
1–4 | 17.4 | 39.3 | 39.3 (30.4 to 48.2) | 82.6 (77.5 to 87.7) | 2.3 (1.6 to 3.3) | 0.7 (0.6 to 0.9) | |
5–14 | 34.0 | 63.4 | 63.4 (52.3 to 74.5) | 66.0 (58.5 to 73.5) | 1.9 (1.4 to 2.5) | 0.6 (0.4 to 0.8) | |
Difficult/laboured breathing | <1 | 19.5 | 16.0 | 16.0 (7.6 to 24.5) | 80.5 (68.4 to 92.6) | 0.8 (0.4 to 1.9) | 1.0 (0.9 to 1.3) |
1–4 | 14.1 | 9.3 | 9.3 (4.1 to 14.6) | 85.9 (81.2 to 90.6) | 0.7 (0.3 to 1.3) | 1.1 (1.0 to 1.1) | |
5–14 | 10.5 | 6.8 | 6.8 (1.0 to 12.6) | 89.5 (84.7 to 94.4) | 0.7 (0.2 to 1.7) | 1.0 (1.0 to 1.1) |
Standardised to UK case-fatality rates (CFR) using weighted mean frequency (CFR = 4.5% for children <1 year; 3.3% for children 1–4 years; 3.0% for children 5–14 years).