OBJECTIVES: To compare 3 communication modes (postal, fax, and e-mail) in a rotavirus vaccine physician survey. METHODS: We used 3 communication modes to distribute a survey to physicians listed in the membership directory of the Georgia Chapter of the American Academy of Pediatrics. The directory listed 1391 members; however, 404 were deemed ineligible on the basis of their listing as a specialist, retiree, resident in training, or government public health employee. Of the 987 members expected to administer vaccines, 150 were selected randomly to receive the postal survey (postal group). Of the remaining listings, 488 (58%) of 837 listed a fax number; 150 members were selected randomly and faxed a survey (fax group). Of the remaining members, 266 (39%) of 687 had e-mail addresses listed; 150 members were selected randomly for the e-mail survey (e-mail group). A follow-up survey was sent by the same mode at 2 weeks. A final survey was sent via another mode (mixed mode) at 1 month: by fax to e-mail and postal nonresponders and by post to fax nonresponders and those without fax. RESULTS: Eligible respondents in the 3 survey groups were similar in their practice setting and location. Although the e-mail group had fewer median years (8 years) since medical school graduation than the fax group (19 years) and postal group (17 years), a similar percentage of responders in all groups had computers (>85%) and Internet access (> or =70%) at work. However, only 39% of members listed an e-mail address in the directory. In the 2 weeks after the first mailing, 39 surveys were completed via postal mail, 50 via fax, and 16 via e-mail. In the 2 weeks after the second contact (sent at 2 weeks), 20 surveys were completed via postal mail, 15 via fax, and 17 via e-mail. The response rate after the first 2 mailings was 41% (59 of 143) for postal, 47% (65 of 137) for fax, and 26% (33 of 125) for e-mail surveys. The third and final survey (sent 1 month after the first mailing) was sent by a different (ie, mixed) mode and elicited an additional 73 responses: 19 responses (15 postal, 4 fax) from the postal group, 19 responses (18 postal, 1 fax) from the fax group, and 35 responses (15 postal, 13 fax, 7 e-mail) from the e-mail group. Twenty-three percent (9 of 40) of the e-mail and 18% (15 of 83) of the fax surveys completed were returned on the same or subsequent day they were sent, compared with none of the postal surveys. There were significant differences among the 3 groups for invalid addresses/numbers (4% postal, 8% fax, and 16% e-mail) listed in the directory. Using mixed modes as the third contact, the overall response rate increased from 39% before mixed mode to a final of 53%. On the basis of the 3 initial groups, responses to 1 of 12 rotavirus questions differed significantly. CONCLUSIONS: Future use of e-mail surveys in selected circumstances is promising, because the majority of providers have Internet access and acknowledged interest in participating in e-mail surveys. E-mail surveys could be especially useful if rapid response time is necessary. There were fewer incomplete questions by participants who completed the e-mail survey compared with postal or fax participants. Updating membership e-mail addresses and routinely using e-mail as a communication tool should improve the ability to use e-mail surveys. There may need to be ongoing evaluations that critically evaluate providers' responses to e-mail surveys compared with other survey modes before e-mail surveys can become a standard survey tool. In the meantime, mixed-mode surveys may be an option.