Table 1.
Questions used to assess asthma states at each examination
| Has a doctor or nurse ever said that you have asthma? | If yes, at what age were you first told this? | Have you had this (asthma) in the past year? OR Are you taking medications for asthma or any breathing problem? | |||
|---|---|---|---|---|---|
| Time of question administration | Time i | Time i+1 | Time i | Time i+1 | |
| Never asthma (time i+1) | No | No | N/A | No | No |
| Incident asthma (time i+1) | No | Yes | Self-reported year of incidence to determine adult-onset asthma | N/A | N/A |
| Persistent asthma (time i+1) | Yes | Yes | — | Yes | Yes |
| Recrudescent asthma (time i+1) | Yes | Yes | — | No | Yes |
| Quiescent asthma (time i+1) | Yes | Yes | — | Yes/No | No |
Definition of abbreviation: N/A = not applicable.
The medication-related component of the definition in the last column is limited by our equating the “need” for the medication with “report of taking” the medication under a prescription.