The Role of Supplementary Material in Journal Articles QT

Summary

Questionnaires are frequently used in online research, however recruiting, and completion rates of online participants from a variety of cultures and demographic backgrounds can be challenging. The challenge is greater in an online cohort because there is no way to observe the participant beyond what is contributed online. Poor recruiting and completion can result in underpowered research that may not be representative of the sample population. This can trigger an increase in costs as the recruitment period may have to be extended until sample size is reached. When recruiting and completion rates are inadequate studies may have to be terminated and the answer to the research question can remain unknown.

To mitigate these challenges, incentives may be offered in the form of gift certificate draws. There is uncertainty about whether this strategy is effective in online research and if the value of the incentive alters the outcome. A randomised trial can be used to test the intervention to establish an evidence base.

This study (SupMatQT) proposes to link with a large 20,000 person international cohort study (SupMat) that will test the utility and preferences of journal supplementary materials for reviewers, authors,and readers. The research described here will examine the evidence of effect for offering a prize draw incentive on rates of recruitment, and completion for consented participants. All participants will be entered in the draw. Information about the value of the incentive of a prize draw will differ according to what group a participant is randomized to. The entry in the prize draw will not be conditional on levels of participation or group allocation.

The other question researchers will address is what effect do survey reminders have on outcomes? All non-responders will be sent an initial reminder to complete the survey (Group A) and for those who have still not responded a second reminder will be sent 14 days later (Group B). Outcomes will be compared at three time points: for initial response, following reminder 1(Group A), and following reminder 2 (Group B).

Conditions

• Incentive

Interventions

OTHER

Group 1 information

Group 1 prize draw information for participants to win 100% of an Amazon gift card (or currency equivalent) in invitation letter.

OTHER

Group 2 information

Group 2 prize draw information for participants to win 75% of an Amazon gift card (or currency equivalent) in invitation letter.

OTHER

Group 3 information

Group 3 prize draw information for participants to win 50% of an Amazon gift card (or currency equivalent) in invitation letter.

OTHER

Group 4 information

Group 4 prize draw information for participants to win 25% of an Amazon gift card (or currency equivalent) in invitation letter.

OTHER

Group 5 no information

Group 5 no Information for participants to enter a draw to win an Amazon gift card (or currency equivalent) in invitation letter.

OTHER

Group A Reminder

One survey reminder at 14 days

OTHER

Group B Reminders

Two survey reminders one at 14 days and one at 28 days

Sponsors & Collaborators

• The BMJ

  collaborator OTHER

• University of Oxford

  collaborator OTHER

• Queen's University, Belfast

  collaborator OTHER

• ThinkWell

  lead OTHER

Principal Investigators

• Mike Clarke, PhD · Queens University Belfast

Study Design

Allocation

RANDOMIZED

Purpose

HEALTH_SERVICES_RESEARCH

Masking

DOUBLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2016-11-15

Primary Completion

2017-02-15

Completion

2019-02-25

Countries

• United Kingdom

Study Locations