The number of cancer survivors is growing globally and there is extensive interest in investigating the experiences and patient-reported outcomes of those living with and after cancer. Postal surveys have been used to collect data on many patient-reported outcomes. However, non-response can pose problems including reducing the statistical power of the study and limiting the generalisability of findings. It is crucial to identify successful, cost-effective strategies to maximise the response of cancer patients and survivors to questionnaires.
As part of the HRB-funded PiCTure (Prostate Cancer Treatment, your experience) study researchers at the Registry compared two modest monetary incentives (i) the unconditional inclusion of a €1 lottery scratch card with the postal questionnaire the ‘lottery arm’ verses (ii) entry into a prize draw with the chance of winning a €300 voucher conditional upon questionnaire completion ‘prize arm’ – for their effect on the response rate to a postal questionnaire and their relative cost-effectiveness, among 4,820 prostate cancer survivors’ in Ireland.
Inclusion of a €1 lottery scratch card resulted in a statistically significant but modest 2.6% increase in response compared to the conditional incentive of entry into a prize draw when all responders were considered. However, the effect was most pronounced in long-term cancer survivors i.e. those who were 5 years or more beyond their diagnosis. The costs per completed questionnaire were higher in the lottery than the prize arms.
This is the first time that a lottery scratch card incentive has been shown to have a positive effect on questionnaire response among cancer survivors. The findings suggest that, although more expensive, to optimise response to postal questionnaires among cancer survivors, researchers might consider inclusion of a lottery scratch card.