| Literature DB >> 4009104 |
A K Mortagy, J B Howell, W E Waters.
Abstract
A mailed questionnaire was sent to 2712 subjects asking about respiratory symptoms, and a raffle for three prizes of 50 pounds, 30 pounds, and 20 pounds was organised. The response rate in the 1762 who were told about the raffle was no higher than for 950 subjects who served as controls.Mesh：
Year: 1985 PMID： 4009104 PMCID： PMC1052430 DOI： 10.1136/jech.39.2.183
Source DB: PubMed Journal: J Epidemiol Community Health ISSN： 0143-005X Impact factor: 3.710