A comparison of two mail-based strategies to recruit older cancer survivors into a randomized controlled trial of a lifestyle intervention

PURPOSE: To compare response rates to business letter versus greeting card invitations used to recruit older cancer survivors to a randomized controlled clinical trial of a lifestyle intervention METHODS: Capitalizing upon recruitment efforts for a lifestyle intervention trial among older cancer survivors, we explored response rates to study invitations formatted as greeting cards versus standard business letters. Survivors were identified from cancer registries and medical records and randomly assigned with strata defined by gender and racial/ethnicity to one-of-the-two invitations. Both groups received telephone follow-up. RESULTS: Contact was verified among 708 survivors with an average age of 72 years with most being non-Hispanic White (NHW), urban dwelling, and female. Survivors assigned to the business letter (n = 360) as compared to the greeting card (n = 348) were significantly more likely to express interest in participation (OR 1.73, 95% CI 1.11–2.70). With the exception of racial/ethnic minorities (OR 0.73; 95% CI 0.26–2.11), all other subgroups favored the business letter with significance observed in females (OR 1.66, 95% CI 1.00–2.74), NHWs (OR 2.12; 95% CI 1.29–3.49), and rural dwellers (OR 3.61; 95% CI 1.49–8.76). Moreover, the business letter costs were substantially lower than the card. CONCLUSION: Clinical trial recruitment is significantly more effective if solicitations are formatted as standard business letters as compared to greeting cards, though this may not generalize to racial/ethnic minorities where more research is warranted. IMPLICATIONS FOR CANCER SURVIVORS: These study findings are not only valuable to researchers but also have the potential to improve recruitment and engagement of older cancer survivors in clinical trials. CLINICAL TRIAL REGISTRATION: Harvest for Health for in Older Cancer Survivors, ClinicalTrials.gov Identifier: NCT02985411