Table 2 Reasons not to participate in the consecutive recruitment phases
Letter returned (n = 1483) | Â | Â |
|---|---|---|
Reasons not to participate | Total (n) | Percentage |
Few or no complaints | 710 | 48.4% |
Other allergy | 240 | 16.4% |
Study too burdensome | 202 | 13.8% |
No interest in the study | 186 | 12.6% |
No reason | 145 | 9.8% |
Telephone screening (n = 572) | Â | Â |
No HDM allergy | 159 | 27.8% |
Low symptom score (<4/12) | 158 | 27.6% |
Not interested in study | 57 | 10.0% |
Severe asthma | 39 | 6.8% |
Language barrier | 27 | 4.7% |
Use of immunotherapy in the last 3 years | 19 | 3.3% |
Refusing blood sample to be taken | 17 | 3.0% |
Age (out of range) | 15 | 2.6% |
Allergic complaints <1 year | 12 | 2.1% |
History of severe allergic reaction | 9 | 1.6% |
Systemic disease | 8 | 1.4% |
Use of nasal corticosteroids 1 month before baseline | 7 | 1.2% |
Answer forms received after deadline of inclusion period | 45 | 7.9% |
Screening visit (n = 249) | Â | Â |
Only grass pollen or tree pollen sensitization | 81 | 32.5% |
No sensitization detectable | 75 | 30.1% |
Sensitive to pet at home (confirmed by RAST) | 60 | 24.1% |
No informed consent | 29 | 11.7% |
Use of unallowed co-medication | 4 | 1.6% |