A randomised controlled trial of email versus mailed invitation letter in a national longitudinal survey of physicians.

Despite their low cost, the use of email invitations to distribute surveys to medical practitioners have been associated with lower response rates. This research compares the difference in response rates from using email approach plus online completion rather than a mailed invitation letter plus a c...

Full description

Bibliographic Details
Main Authors: Benjamin Harrap, Tamara Taylor, Grant Russell, Anthony Scott
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2023-01-01
Series:PLoS ONE
Online Access:https://doi.org/10.1371/journal.pone.0289628
_version_ 1827825363728728064
author Benjamin Harrap
Tamara Taylor
Grant Russell
Anthony Scott
author_facet Benjamin Harrap
Tamara Taylor
Grant Russell
Anthony Scott
author_sort Benjamin Harrap
collection DOAJ
description Despite their low cost, the use of email invitations to distribute surveys to medical practitioners have been associated with lower response rates. This research compares the difference in response rates from using email approach plus online completion rather than a mailed invitation letter plus a choice of online or paper completion. A parallel randomised controlled trial was conducted during the 11th annual wave of the nationally representative Medicine in Australia: Balancing Employment and Life (MABEL) longitudinal survey of doctors. The control group was invited using a mailed paper letter (including a paper survey plus instructions to complete online) and three mailed paper reminders. The intervention group was approached in the same way apart from the second reminder when they were approached by email only. The primary outcome is the response rate and the statistical analysis was blinded. 18,247 doctors were randomly allocated to the control (9,125) or intervention group (9,127), with 9,108 and 9,107 included in the analysis. Using intention to treat analysis, the response rate in the intervention group was 35.92% compared to 37.59% in the control group, a difference of -1.66 percentage points (95% CI: -3.06 to -0.26). The difference was larger for General Practitioners (-2.76 percentage points, 95% CI: -4.65 to -0.87) compared to other specialists (-0.47 percentage points, 95% CI: -2.53 to 1.60). For those who supplied an email address, the average treatment effect on the treated was higher at -2.63 percentage points (95% CI: -4.50 to -0.75) for all physicians, -3.17 percentage points (95% CI: -5.83 to -0.53) for General Practitioners, and -2.1 percentage points (95% CI: -4.75 to 0.56) for other specialists. For qualified physicians, using email to invite participants to complete a survey leads to lower response rates compared to a mailed letter. Lower response rates need to be traded off with the lower costs of using email rather than mailed letters.
first_indexed 2024-03-12T02:49:00Z
format Article
id doaj.art-32ceba7afec34f99bbcb101fc5bb61f4
institution Directory Open Access Journal
issn 1932-6203
language English
last_indexed 2024-03-12T02:49:00Z
publishDate 2023-01-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS ONE
spelling doaj.art-32ceba7afec34f99bbcb101fc5bb61f42023-09-04T05:31:59ZengPublic Library of Science (PLoS)PLoS ONE1932-62032023-01-01188e028962810.1371/journal.pone.0289628A randomised controlled trial of email versus mailed invitation letter in a national longitudinal survey of physicians.Benjamin HarrapTamara TaylorGrant RussellAnthony ScottDespite their low cost, the use of email invitations to distribute surveys to medical practitioners have been associated with lower response rates. This research compares the difference in response rates from using email approach plus online completion rather than a mailed invitation letter plus a choice of online or paper completion. A parallel randomised controlled trial was conducted during the 11th annual wave of the nationally representative Medicine in Australia: Balancing Employment and Life (MABEL) longitudinal survey of doctors. The control group was invited using a mailed paper letter (including a paper survey plus instructions to complete online) and three mailed paper reminders. The intervention group was approached in the same way apart from the second reminder when they were approached by email only. The primary outcome is the response rate and the statistical analysis was blinded. 18,247 doctors were randomly allocated to the control (9,125) or intervention group (9,127), with 9,108 and 9,107 included in the analysis. Using intention to treat analysis, the response rate in the intervention group was 35.92% compared to 37.59% in the control group, a difference of -1.66 percentage points (95% CI: -3.06 to -0.26). The difference was larger for General Practitioners (-2.76 percentage points, 95% CI: -4.65 to -0.87) compared to other specialists (-0.47 percentage points, 95% CI: -2.53 to 1.60). For those who supplied an email address, the average treatment effect on the treated was higher at -2.63 percentage points (95% CI: -4.50 to -0.75) for all physicians, -3.17 percentage points (95% CI: -5.83 to -0.53) for General Practitioners, and -2.1 percentage points (95% CI: -4.75 to 0.56) for other specialists. For qualified physicians, using email to invite participants to complete a survey leads to lower response rates compared to a mailed letter. Lower response rates need to be traded off with the lower costs of using email rather than mailed letters.https://doi.org/10.1371/journal.pone.0289628
spellingShingle Benjamin Harrap
Tamara Taylor
Grant Russell
Anthony Scott
A randomised controlled trial of email versus mailed invitation letter in a national longitudinal survey of physicians.
PLoS ONE
title A randomised controlled trial of email versus mailed invitation letter in a national longitudinal survey of physicians.
title_full A randomised controlled trial of email versus mailed invitation letter in a national longitudinal survey of physicians.
title_fullStr A randomised controlled trial of email versus mailed invitation letter in a national longitudinal survey of physicians.
title_full_unstemmed A randomised controlled trial of email versus mailed invitation letter in a national longitudinal survey of physicians.
title_short A randomised controlled trial of email versus mailed invitation letter in a national longitudinal survey of physicians.
title_sort randomised controlled trial of email versus mailed invitation letter in a national longitudinal survey of physicians
url https://doi.org/10.1371/journal.pone.0289628
work_keys_str_mv AT benjaminharrap arandomisedcontrolledtrialofemailversusmailedinvitationletterinanationallongitudinalsurveyofphysicians
AT tamarataylor arandomisedcontrolledtrialofemailversusmailedinvitationletterinanationallongitudinalsurveyofphysicians
AT grantrussell arandomisedcontrolledtrialofemailversusmailedinvitationletterinanationallongitudinalsurveyofphysicians
AT anthonyscott arandomisedcontrolledtrialofemailversusmailedinvitationletterinanationallongitudinalsurveyofphysicians
AT benjaminharrap randomisedcontrolledtrialofemailversusmailedinvitationletterinanationallongitudinalsurveyofphysicians
AT tamarataylor randomisedcontrolledtrialofemailversusmailedinvitationletterinanationallongitudinalsurveyofphysicians
AT grantrussell randomisedcontrolledtrialofemailversusmailedinvitationletterinanationallongitudinalsurveyofphysicians
AT anthonyscott randomisedcontrolledtrialofemailversusmailedinvitationletterinanationallongitudinalsurveyofphysicians