Cookies on this website

We use cookies to ensure that we give you the best experience on our website. If you click 'Accept all cookies' we'll assume that you are happy to receive all cookies and you won't see this message again. If you click 'Reject all non-essential cookies' only necessary cookies providing core functionality such as security, network management, and accessibility will be enabled. Click 'Find out more' for information on how to change your cookie settings.

It is cheap to process epidemiological data from optical mark read (OMR) questionnaires. Respondents should use a pencil to complete OMR questionnaires, but many will not unless these are supplied. Sending pencils and erasers is expensive. Does sending pencils and erasers increase the response rate as cost-effectively as sending reminders, or does this decrease the error rate and offset data checking costs? We mailed 300 smokers and half were randomised to receive pencils and erasers. The relative risk (95% confidence intervals) for the response rate for the pencil group relative to the non-pencil group was 0.77 (0.46-1.29) and for the error rate was 1.31 (0.78-2.21). Sending pencils and erasers was not cost-effective in sensitivity analysis with any response rate or using the confidence intervals. Including pencils with mailed epidemiological questionnaires probably has no benefit and any plausible benefit does not offset the costs of sending pencils and erasers.

Original publication




Journal article


Public Health

Publication Date





80 - 81