Response to screening questionnaire and home interview in the 1991 and 2002 studies
| Detail | 1991 | 2002 |
|---|---|---|
| Note: Response rates have been calculated after excluding false positives as in the third Croydon study no attempt was made to interview subjects identified as false positives at initial phone contact. | ||
| †66% random sample. | ||
| ‡In 1991 10 stopped wheezing at interview (interviewed as former wheezers). | ||
| Population targeted | 3786 | 4246 |
| Forms returned | 3070 | 3111 |
| Response rate | 81% | 73% |
| Wheeze in previous 12 months | 395 | 555 |
| Sought for home interview | 395 | 366† |
| False positives | 7 | 9 |
| Sought for home interview excluding false positives | 388 | 357 |
| Interview obtained | 312 | 198 |
| Response rate | 80% | 55% |
| Exclusions‡ | 10 | 0 |
| After exclusions | 302 | 198 |