Evaluation of Reminder Strategies (Emails and Text Messages) to Increase Participation in the Le French Gut E-cohort

NCT07473466 | Completed DMC

• 1 other identifier: LFGxSKEZI-2024-001
• Study Type: interventional
• Target: 20,487
• Locations: 1 country
• Sites: 1

Brief Summary

This study is a randomized controlled trial nested in the "Le French Gut" e-cohort aiming to test the efficacy of 4 reminder strategies (emails and/or SMS with standard and/or institutional wording) in increasing participation of inactive volunteers. This trial is led in collaboration between the "Le French Gut" project and SKEZI, a DeepTech start-up which markets the data collection solution (SKEZIA online platform) for the "Le French Gut" project and carries out the InnoPRO program, aimed at generating new knowledge in the field of e-cohorts.

Conditions

General Population (no Specific Condition or Disease)

Keywords

e-cohort; reminder strategy; response rate; email reminder; text message reminder; completion; inclusion

Outcome Measures

Primary Outcomes (1)

• Completion rate

  Proportion of participants who complete the "A propos de vous" questionnaire within 30 days after the last reminder, calculated as number of participants who fully completed the questionnaire divided by total number of participants included in the study (or arm)

  30 days post-reminder

Secondary Outcomes (3)

• Completion time

  30 days post-reminder

• Login rate

  30 days post-reminder

• Login time

  30 days post-reminder

Other Outcomes (2)

• Email opening rate

  30 days post-reminder

• Email click-through rate

  30 days post-reminder

Study Arms (4)

standard emails only

EXPERIMENTAL

Standard, semi-formal worded email inviting participants to complete the online "A propos de vous" (personal information) questionnaire in order to validate their participation in the "Le French Gut" cohort.

Other: 3 standard email reminders

institutional emails only

EXPERIMENTAL

Institutional, formal-worded email, signed by the study coordinator, inviting participants to complete the online "A propos de vous" (personal information) questionnaire in order to validate their participation in the "Le French Gut" cohort.

Other: 3 institutional email reminders

SMS only

EXPERIMENTAL

Short text message inviting participants to complete the online "A propos de vous" (personal information) questionnaire in order to validate their participation in the "Le French Gut" cohort.

Other: 3 SMS reminders

Combined reminders

EXPERIMENTAL

Combined sequence of reminders: first, the standard email; second, the SMS; third, the institutional email. The contents of the reminders are similar to those of the three other parallel groups inviting participants to complete the online "A propos de vous" (personal information) questionnaire in order to validate their participation in the "Le French Gut" cohort.

Other: Combined reminders

Interventions

3 standard email reminders OTHER

The same standard email is sent three times to participants, each email spaced 72 hours apart.

standard emails only

3 institutional email reminders OTHER

The same institutional email is sent three times to participants, each email spaced 72 hours apart.

institutional emails only

3 SMS reminders OTHER

The same SMS (brief text message) is sent three times to participants, each SMS spaced 72 hours apart.

SMS only

Combined reminders OTHER

Three reminders are sent to participants, each reminder spaced 72 hours apart: the first reminder is a standard email, the second reminder is a SMS, the third reminder is a institutional email.

Combined reminders

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Being registered on the "Le French Gut" platform but not active participant (e.i. eligibility questionnaire not completed, "Le French Gut" consent not validated, "A propos de vous" questionnaire not completed)
• Having provided a valid email address and/or mobile-phone number

You may not qualify if:

• Completed "A propos de vous" questionnaire before the first reminder
• Being non eligible to the "Le French Gut" cohort (eligibility to "Le Fench Gut" cohort: being over 18 years-old and living in France)

Sponsors & Collaborators

• SKEZI: lead
• Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement: collaborator

Study Sites (1)

SKEZI

Paris, France

Location

MeSH Terms

Conditions

Disease

Condition Hierarchy (Ancestors)

Pathologic Processes; Pathological Conditions, Signs and Symptoms

Study Officials

• Jean-Philippe Bertocchio, MD, PhD

  SKEZI

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, INVESTIGATOR, OUTCOMES ASSESSOR
• Masking Details: Participants were unaware that the trial was being conducted, and the researchers and data analysts were blind to participants' assigned groups.
• Purpose: OTHER
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: CEO, PhD, MD

Model Details: Randomized, parallel groups, 4-arm, 1:1:1:1 allocation ratio, stratified (by time-since-registration: : ≤ 6 months, 6-12 months, 12-18 months, \>18 months), blinded (data analyst blind to allocation and participants unaware of the trial being conducted)

Study Record Dates

• First Submitted: March 11, 2026
• First Posted: March 16, 2026
• Study Start: November 7, 2024
• Primary Completion: November 25, 2024
• Study Completion: November 25, 2024
• Last Updated: March 17, 2026

Record last verified: 2026-03

Locations

FR (1)