Patient Portal Reminder/Recall for Influenza Vaccination in a Health System- RCT 2

Sub-optimal vaccination rates are a significant problem in the U.S., despite their effectiveness in preventing morbidity and mortality from vaccine-preventable illness. For influenza specifically, annual epidemics of influenza cause substantial morbidity in the U.S. with up to 40,00-80,000 deaths/year and many hospitalizations, emergency and outpatient visits, and significant costs.

Reminder/recall (R/R), sent by phone, mail or other modality, can improve child and adult influenza vaccination rates. However, the majority of pediatric or adult primary care practices to not conduct R/R. Barriers are lack of finances, personnel, and algorithms to identify eligible patients.

A technological breakthrough that might overcome these barriers involves patient portals-- secure, web-based communication systems, embedded within electronic health records (EHRs), for patients and providers to communicate with each other via email and the internet. Portals are used by about half of Americans and half of UCLA patients.

There has been considerable research on how best to communicate about vaccines with families. A number of studies have examined the impact of gain-framed (messages emphasizing the benefits of vaccination) versus loss-framed (messages emphasizing the risks of not getting vaccinated); however, the findings have been inconsistent across studies and by sub-population.

In addition to framing, another potential influence on the decision to vaccinate is pre-commitment. Previous studies suggest that, upon being prompted, indicating an intention to do something increases the likelihood of following through. Therefore, a pre-commitment prompt is being asked of half the participants in each arm to evaluate its impact on influenza vaccination.

The purpose of this randomized controlled trial is to evaluate the impact of gain-framed and loss-framed reminder-recall messages sent via the patient portal, pre-commitment prompts sent via the patient portal, and the interactions between the two type of messages and pre-commitment on influenza vaccination among UCLA Health System's primary care patients aged 6 months and older.

The proposed design of this randomized-controlled trial is a 3 x 2 factorial design.

Standard of care control (no reminder messages, no pre-commitment prompt) No portal messages, pre-commitment prompt Gain-framed portal messages, pre-commitment prompt Gain-framed portal messages, no pre-commitment prompt Loss-framed portal messages, pre-commitment prompt Loss-framed portal messages, no pre-commitment prompt

Hyp 1. Vaccination rates will differ by receipt of no reminders, gain-framed reminders and loss-framed reminders.

1a. Vaccination rates will be higher among patients receiving gain-framed reminders than among patients receiving no reminders.

1b. Vaccination rates will be higher among patients receiving loss-framed reminders than among patients receiving no reminders.

1c. Vaccination rates will be higher among patients receiving gain-framed reminders than among patients receiving loss-framed reminders.

Hyp 2. Vaccination rates will be higher among patients receiving a pre-commitment prompt than among patients not receiving any prompt.

For relevant study arms, the first R/R messages will be sent in October 2019.