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Updated: May 23, 2026

E-Patient Counseling Trial (E-PACO): Computer Based Education versus Nurse Counseling for Patients to Prepare for Colonoscopy
Published on: August 1, 2019
No difference demonstrated between faxed or mailed prenotification in promoting questionnaire response among family
Melina Gattellari1, Nicholas Zwar, John M Worthington
1School of Public Health and Community Medicine, The University of New South Wales, Ingham Institute for Applied Medical Research, Centre for Research Management, Evidence and Surveillance, Sydney South West Area Health Service, Locked Bag 7008, Liverpool NSW 1871, Australia. melina.gattellari@sswahs.nsw.gov.au
Objective:
Achieving high survey participation rates among physicians is challenging. We aimed to assess the effectiveness of response-aiding strategies in a postal survey of 1,000 randomly selected Australian family physicians (FPs).
Study Design And Setting:
A two × two randomized controlled trial was undertaken to assess the effectiveness of a mailed vs. faxed prenotification letter and a mailed questionnaire sealed with a label marked attention to doctor vs. a control label. At the time of our final reminder, we randomized remaining nonresponders to receive a more or less personalized mail-out.
Results:
Response did not significantly differ among eligible FPs receiving a prenotification letter via mail or fax. However, 25.6% of eligible FPs whose questionnaires were sealed with a label marked attention to the doctor responded before reminders were administered and compared with 18.6% of FPs whose questionnaires were sealed with a control label (P=0.008). Differences were not statistically significant thereafter. There was no significant difference in response between FPs who received a more vs. less personalized approach at the time of the final reminder (P=0.16).
Conclusion:
Mail marked attention to doctor may usefully increase early response. Prenotification letters delivered via fax are equally effective to those administered by mail and may be cheaper.
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