Validity of each question as a tool for identifying atopic status
| Question | Negative response to question, n (%) | Sensitivity, % (95% CI) | Specificity, % (95% CI) | Positive predictive value, % (95% CI) | Negative predictive value, % (95% CI) |
|---|---|---|---|---|---|
| 1. Are you aged <40 years? | 73 (51.1) | 53 (42 to 64) | 56 (43 to 69) | 61 (49 to 73) | 48 (36 to 60) |
| 2. Do you have, or have you ever had, hayfever? | 73 (51.0) | 68 (57 to 78) | 75 (63 to 86) | 79 (67 to 87) | 64 (52 to 75) |
| 3. Do any of your parents or siblings (brothers or sisters) have, or have they ever had, hayfever? | 79 (55.2) | 59 (48 to 70) | 74 (62 to 84) | 75 (63 to 85) | 58 (47 to 69) |
| 4. Do you have, or have you ever had, asthma? | 96 (67.1) | 43 (32 to 54) | 80 (69 to 90) | 74 (60 to 86) | 52 (42 to 62) |
| 5. Did you ever have eczema or asthma as a baby (aged <2 years)? | 114 (79.7) | 27 (18 to 38) | 89 (78 to 95) | 76 (56 to 90) | 48 (38 to 58) |
| 6. Do you have, or have you ever had, any other allergy? | 56 (39.2) | 69 (58 to 79) | 50 (37 to 62) | 64 (53 to 74) | 55 (41 to 69) |
| 7. Do you ever have any symptoms of itch or sneeze? | 25 (17.5) | 91 (83 to 96) | 29 (18 to 42) | 62 (53 to 71) | 72 (51 to 88) |
| 8. Do your allergy symptoms vary when you go from place to place (for example, on holiday)? | 61 (43.0) | 75 (64 to 84) | 66 (53 to 78) | 74 (63 to 83) | 67 (54 to 79) |
| 9. Is there a specific trigger that always sets off your allergy symptoms? | 76 (53.2) | 62 (50 to 72) | 73 (60 to 83) | 74 (63 to 84) | 59 (47 to 70) |
| 10. Do your allergy symptoms start within 30 minutes of being exposed to a specific trigger? | 64 (44.8) | 69 (58 to 79) | 63 (50 to 75) | 71 (60 to 81) | 61 (48 to 73) |
| 11. Do your allergy symptoms improve after treatment with antihistamines? | 58 (40.6) | 72 (61 to 81) | 56 (43 to 69) | 68 (57 to 78) | 60 (47 to 73) |