Nudging Preventive Screening Via Message Framing and Bundling

Summary

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").

Conditions

• Breast Neoplasms
• Uterine Cervical Neoplasms
• Colorectal Neoplasms
• Prostatic Neoplasms
• Diabetes Mellitus
• Dyslipidemias

Interventions

BEHAVIORAL

Basic cancer screening message

Patients receive a WhatsApp message naming their recommended cancer screening exam and describing it as the test recommended for their age group.

BEHAVIORAL

Basic chronic disease test message

Patients receive a WhatsApp message naming the recommended chronic disease test and describing it as the test recommended for their age group.

BEHAVIORAL

Basic combined message

Patients receive a WhatsApp message naming both the recommended cancer screening and the chronic disease test, and describing them as the tests recommended for their age group.

BEHAVIORAL

Risk framing cancer screening message

Patients receive a WhatsApp message naming their recommended cancer screening exam and emphasizing that (1) the recommendation is based on health risks common to their age group and (2) early detection can be life-saving

BEHAVIORAL

Risk framing chronic disease test message

Patients receive a WhatsApp message naming the recommended chronic disease test and emphasizing that (1) the recommendation is based on health risks common to their age group and (2) early detection can be life-saving.

BEHAVIORAL

Risk framing combined message

Patients receive a WhatsApp message naming both exams and emphasizing that (1) the recommendation is based on health risks common to their age group and (2) early detection can be life-saving.

BEHAVIORAL

Peace of mind framing cancer screening message

Patients receive a WhatsApp message naming their recommended cancer screening exam and emphasizing that getting the exam done on time will give them peace of mind about their health.

BEHAVIORAL

Peace of mind framing chronic disease test message

Patients receive a WhatsApp message naming the recommended chronic disease and emphasizing that getting the exam done on time will give them peace of mind about their health.

BEHAVIORAL

Peace of mind framing combined message

Patients receive a WhatsApp message naming both exams and emphasizing that getting the exams done on time will give them peace of mind about their health.

Sponsors & Collaborators

• University of Chile

  lead OTHER

Study Design

Allocation

RANDOMIZED

Purpose

HEALTH_SERVICES_RESEARCH

Masking

SINGLE

Model

FACTORIAL

Eligibility

Min Age

21 Years

Max Age

74 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2026-06-08

Primary Completion

2026-09-08

Completion

2026-12-08