Encouraging Older Adults and Adults With Serious Illness to Designate a Health Care Proxy

A Randomized Trial to Encourage Older Adults and Adults With Serious Illness to Designate a Health Care Proxy

This study is a Stage III randomized trial to encourage patients in advance of a health care appointment to designate a healthcare proxy. Patients will be randomly assigned to receive a mailer containing information about designating a healthcare proxy, or to not receive any mailer. For patients assigned to receive a mailer, the mailer will differ by the presence or absence of a patient pre-commitment prompt, and contain a personalized provider request or a generic health system request. The work will evaluate the randomized trial and identify factors that predict intervention effectiveness.

Study Overview

• Status: Not yet recruiting
• Conditions: Designating a Healthcare Proxy
• Intervention / Treatment: Behavioral: Mailer; Behavioral: Pre-commitment Prompt; Behavioral: Provider Request

• Study Type: Interventional
• Enrollment (Estimated): 10000
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Mireille Jacobson, PhD; Phone Number: 213-821-8296; Email: mireillj@usc.edu
• Study Contact Backup: Name: Tara K Knight, PhD; Email: knight@usc.edu

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• No EHR-documented healthcare proxy at enrollment
• Age ≥ 55 years OR age ≥ 18 years and listed in the health system's cancer, CHF, or CKD registries

Exclusion Criteria:

• None

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Health Services Research
• Allocation: Randomized
• Interventional Model: Factorial Assignment
• Masking: None (Open Label)

Number of Arms

5

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
No Intervention: No Mailer Control; Patients will not receive a mailer.
Experimental: Provider Mailer with a Pre-commitment Prompt; Patients will receive a mailer containing a pre-commitment prompt to bring in a form listing their healthcare proxy to their next primary care visit. The mailer will be sent from and signed by their primary care provider.	Behavioral: Mailer; Patient mailers will ask the patient to name a healthcare proxy at their next primary care visit.; Behavioral: Pre-commitment Prompt; Patient mailers will contain a box that asks the patient to bring a form with their choice for a healthcare proxy to their next primary care visit.; Behavioral: Provider Request; Patient mailers will be sent from and signed by the patient's provider for their next scheduled primary care visit.
Experimental: Health System Mailer with a Pre-commitment Prompt; Patients will receive a mailer containing a pre-commitment prompt to bring in a form listing their healthcare proxy to their next primary care visit. The mailer will be sent from and signed by the health system	Behavioral: Mailer; Patient mailers will ask the patient to name a healthcare proxy at their next primary care visit.; Behavioral: Pre-commitment Prompt; Patient mailers will contain a box that asks the patient to bring a form with their choice for a healthcare proxy to their next primary care visit.
Experimental: Provider Mailer without a Pre-commitment Prompt; Patients will receive a mailer, but it will not contain a pre-commitment prompt to bring in a form listing their healthcare proxy to their next primary care visit. The mailer will be sent from and signed by the patient's provider.	Behavioral: Mailer; Patient mailers will ask the patient to name a healthcare proxy at their next primary care visit.; Behavioral: Provider Request; Patient mailers will be sent from and signed by the patient's provider for their next scheduled primary care visit.
Experimental: Health System Mailer without a Pre-commitment Prompt; Patients will receive a mailer, but it will not contain a pre-commitment prompt to bring in a form listing their healthcare proxy to their next primary care visit. The mailer will be sent from and signed by the health system.	Behavioral: Mailer; Patient mailers will ask the patient to name a healthcare proxy at their next primary care visit.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Proportion of patients with EHR-documented healthcare proxy	Documentation in the electronic health record of a healthcare proxy	Within 30 days of the patient's first scheduled primary care visit

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Proportion of patients that attended scheduled visit	Patient attended the scheduled primary care visit	On the date of the patient's first scheduled primary care visit
Proportion of patients with EHR-documented healthcare proxy within 90 days	Documentation in the electronic health record of a healthcare proxy	Within 90 days of the patient's first scheduled primary care visit
Proportion of patients with primary care visit within 90 days	Patient attended a primary care visit	Within 90 days of the patient's first scheduled primary care visit
Proportion of patients with legal advance care planning documentation	Documentation in the electronic health record of any legal advance care planning document, including an advance directive or power of attorney	Within 30 days of the patient's first scheduled primary care visit
Proportion of patients with legal advance care planning documentation within 90 days	Documentation in the electronic health record of any legal advance care planning document, including an advance directive or power of attorney	Within 90 days of the patient's first scheduled primary care visit

Collaborators and Investigators

• Sponsor: University of Southern California
• Collaborators: National Institute on Aging (NIA); Contra Costa Health
• Investigators: Principal Investigator: Mireille Jacobson, PhD, University of Southern California

Study record dates

Study Major Dates

• Study Start (Estimated): June 1, 2026
• Primary Completion (Estimated): June 1, 2027
• Study Completion (Estimated): August 31, 2027

Study Registration Dates

• First Submitted: December 12, 2025
• First Submitted That Met QC Criteria: December 17, 2025
• First Posted (Actual): December 18, 2025

Study Record Updates

• Last Update Posted (Actual): April 22, 2026
• Last Update Submitted That Met QC Criteria: April 17, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Keywords: behavioral economics; advance care planning; end-of-life care; pre-commitment; healthcare proxy; surrogate decision-maker; durable power of attorney
• Other Study ID Numbers: UP-23-01203; P30AG024968 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: De-identified IPD used for results publication may be shared upon request and with approval by the health system.
• IPD Sharing Time Frame: IPD will be available for one year after the study publication date.
• IPD Sharing Access Criteria: IPD access criteria will be governed by a data use agreement signed by both parties.
• IPD Sharing Supporting Information Type: SAP; ANALYTIC_CODE

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No