This study assessed the impact of follow-up reminder phone calls on response rates to a mailed consent form packet.
Patients with rheumatoid arthritis were invited to enroll in a study by signing and returning consent forms by mail. Patients not returning completed study consent forms were called and reminded to return the signed consent forms.
Among 724 mailed consent form packets, 376 (52%) were returned without further follow-up. Follow-up reminder calls were made to 220 of the 348 patients who did not return signed consent forms. Among subjects contacted by phone, 67 (31% of those called) returned signed consent forms.
Follow-up reminder phone calls raised the overall consent rate of 52 to 61%, suggesting that they can be an effective technique in increasing response rates.