REPEATABILITY OF SELF-REPORTED DATA ON OCCUPATIONAL EXPOSURE TO PARTICULAR COMPOUNDS

The repeatability of self-reported occupational exposure to eight part icular compounds was investigated in 209 males aged 49-87 years. The s ubjects completed an initial mailed questionnaire and were interviewed by telephone 3-5 weeks later. The study was carried out as part of a case-referent study on the relation between occupation and prostate ca ncer. The repeatability of answers was found to be better in the case of some agents than in that of others: kappas calculated as a measure of concordance range from 0.36 to 0.70. No substantial influence was f ound to be exercised by age or socioeconomic status, or by case or ref erent status. Although the repeatability observed was not flawless, it was concluded that self-reported exposure data would appear to be a s ound basis for epidemiological studies on the aetiology of disease, wh enever objective information on occupational exposure is not available .