About this trial

This study is a randomized controlled field experiment embedded in the medical institution Early Diagnosis Program in Chile. Participants with two exams pending (a cancer screening test and a chronic disease test for diabetes and dyslipidemia) will be randomly assigned across a 3 × 3 factorial design: three message framing conditions (Basic, Risk/Importance, Peace of Mind) crossed with three exam-type conditions (cancer screening only, chronic disease test only, or both exams). Participants with only a cancer screening pending will be assigned to the 3 framing conditions and be encouraged to get the cancer screening.

In both cases, participants are assigned to each experimental arm at twice the rate of an additional arm receiving the standard message currently used by the medical institution. This standard-message arm is included for operational purposes, is not part of the pre-specified analyses, and is thus not described in the "Arms and Intervention" section (or counted for "number of arms").

Eligibility criteria

Qualifiers

Has at least one pending cancer screening (breast, colorectal, cervical, or prostate) within the contact window, as determined by the medical institution

Aged 21 to 74 years

Has a valid phone number on file

Eligibility is determined operationally before randomization (ex-ante)

Disqualifiers

Participants whose WhatsApp message was not successfully delivered, as reported by the third-party software used by the medical institution.

Trial design

Treatments tested in this trial

  • Basic cancer screening message
  • Basic chronic disease test message
  • Basic combined message
  • Risk framing cancer screening message
  • Risk framing chronic disease test message
  • Risk framing combined message
  • Peace of mind framing cancer screening message
  • Peace of mind framing chronic disease test message
  • Peace of mind framing combined message

Treatment groups

235,000 Participants
are divided into 9 treatment groups

9

Treatment groups

See each treatment group below.

Locations

This trial has no locations

Sponsors and collaborators

University of Chile

Lead sponsor