Covid-19 VaccinationEMPOWeRNCT07838038
Effect of Messaging on Pragmatic Outcomes Within an Integrated Healthcare System
A study testing Vaccine choice message, Vaccine choice + platform-framed message and Vaccine choice + HCP trust-framed message in people with Covid-19 Vaccination, run by Kaiser Permanente at 1 site in United States.
Trial summary
COVID-19 vaccination among patients at high risk for severe disease has declined in the United States since 2022. Prior research, including discrete choice experiments (DCEs), has demonstrated that vaccine preferences are influenced by attributes such as effectiveness, safety, convenience, and protection against… Read more about this study
- Who is it for?
- Ages 18 years and olderHealthy volunteers can take part
- Conditions the study is for
- Covid-19 Vaccination
- What is being tested?
- Vaccine choice message, Vaccine choice + platform-framed message and Vaccine choice + HCP trust-framed message
- Type of treatment
- Vaccines, Lifestyle or therapy programme
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 1,300,000 participants
- Where
- 1 siteUnited States
- Study dates
- 29 Sep 2026to 30 Jun 2027
- Phase
- Interventional
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- Aged ≥18 years;
- Active KPSC member;
- Continuous membership from 27 August 2025 to 28 September 2026;
- Members who are aged 65 years and older, or adults aged 18-64 years with at least one of the following health conditions that increases their risk for severe COVID-19 illness, including: a) asthma, b) cancer, c) ischemic stroke, d) intracerebral or subarachnoid hemorrhage, e) transient ischemic attack, f) chronic kidney disease, g) dialysis, h) bronchiectasis, i) chronic obstructive, pulmonary disease (COPD), j) pulmonary fibrosis, k) cystic fibrosis, l) pulmonary hypertension, m) cirrhosis, n) non-alcoholic fatty liver disease (NALD), o) alcoholic liver disease, p) autoimmune hepatitis, q) diabetes, r) heart failure, s) coronary artery disease, t) cardiomyopathy, u) HIV, v) obesity, w) essential hypertension, x) primary immunodeficiency and other underlying immunocompromising conditions, y) solid organ or blood stem cell transplant, z) tuberculosis;
- No documented receipt of updated 2026-27 COVID-19 vaccine as of 28 September 2026;
- Has valid email information.
Who cannot join
- Unable to receive or opted out of email communication.
- People with unknown or missing sex.
- People who cannot safely receive a COVID-19 vaccine, including those who had a severe allergic reaction to a previous COVID-19 vaccine or have a contraindication to COVID-19 vaccine or a vaccine ingredient, will not be included in the study.
- People with metastatic or terminal illness, advanced illness, receiving hospice or palliative care, or resident in skilled nursing facilities.
- People who are pregnant or currently breastfeeding.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
United States1 site, 1 recruiting
- Recruiting
Kaiser Permanente Southern California, Department of Research & Evaluation
Pasadena, California, 91101
Zendi S Yha, BS, 626-372-5637, zendi.s.yha@kp.org
Annette Regan, PhD, MPH, 626-760-2482, annette.k.regan@kp.org
About this study
Official title: Effect of Messaging on Pragmatic Outcomes Within an Integrated Healthcare System: a Randomized Trial (EMPOWeR)
COVID-19 vaccination among patients at high risk for severe disease has declined in the United States since 2022. Prior research, including discrete choice experiments (DCEs), has demonstrated that vaccine preferences are influenced by attributes such as effectiveness, safety, convenience, and protection against severe disease. Although DCEs provide valuable insights into stated vaccine preferences and decision-making, they rely on hypothetical scenarios and cannot directly assess how vaccine attributes influence real-world vaccine uptake. Additional research is needed to understand the relationship between vaccine characteristics and observed COVID-19 vaccination behavior in routine clinical practice.
The EMPOWeR study is a pragmatic randomized controlled trial conducted within Kaiser Permanente Southern California (KPSC) to evaluate the effect of immunization messages and reminders that highlight COVID-19 vaccine choices on vaccine uptake. The primary research questions are:
Read more
- Does having a choice in COVID-19 vaccine platform affect vaccine uptake among patients at high-risk of severe disease? 1a. Does having a choice in COVID-19 vaccine platform affect vaccine uptake among patients at high-risk of severe disease, when differences in vaccine platform are highlighted? 1b. Does having a choice in COVID-19 vaccine platform affect vaccine uptake among patients at high-risk of severe disease, when a trusted healthcare professional (HCP) endorses both vaccine options? 1c. Does having a choice in COVID-19 vaccine platform affect vaccine uptake among patients at high-risk of severe disease, when vaccine reactogenicity is highlighted? A secondary research question is:
- Does having a choice in COVID-19 vaccine additionally increase uptake of influenza vaccine?
During the 2026-2027 respiratory virus season, eligible KPSC members who are at high-risk of severe COVID-19 will be randomly assigned to receive a standard reminder message or a reminder message with additional information about available COVID-19 vaccine options.
Read the detailed description
The Effect of Messaging on Pragmatic Outcomes Within an Integrated Healthcare System: A Randomized Trial (EMPOWeR) study is designed to learn whether vaccine reminder messages that highlight a patient's choice of COVID-19 vaccines can help increase vaccine uptake among adults who are at higher risk for serious illness from COVID-19. The study will take place within KPSC, a large integrated health care system in southern California, and will use routine health care messages and reminders for updated COVID-19 immunization .
COVID-19 vaccination rates have declined since 2022, including among older adults and people with medical conditions that increase their risk of severe disease. Concerns about vaccine side effects, trust, and vaccine technologies may influence whether people choose to get vaccinated. The EMPOWeR study will evaluate whether providing information about vaccine choices can encourage individuals at higher risk of severe COVID-19 to receive an updated COVID-19 vaccine.
Adults who are eligible for a COVID-19 vaccine and who meet the study eligibility criteria will be included in the study. Eligible participants include adults enrolled for care at KPSC who are either 65 years of age or adults aged 18 to 64 years with certain health conditions that place them at increased risk for severe COVID-19 illness. Participants will not be asked to attend study visits or complete surveys. The study will use immunization data already collected in electronic health records as part of routine care.
Participants will be randomly assigned to one of five groups. One group will receive a standard COVID-19 vaccine reminder message currently used in routine care. The other four groups will receive messages that provide information about available COVID-19 vaccine options: mRNA and protein-based COVID-19 vaccines. These messages may:
- Inform participants that they can choose between two different COVID-19 vaccine types.
- Explain differences between vaccine technologies.
- Include information that both vaccine options are supported by health care professionals.
- Provide information about vaccine side effects and vaccine choice.
All messages will be delivered to eligible participants in early October 2026 using the participant's usual communication preferred language (i.e., English or Spanish). Follow-up reminder messages will also be sent later in the vaccination season (in early December 2026).
The main goal of the study is to determine whether these different messages increase receipt of the updated 2026-2027 COVID-19 vaccine. Additional goals include type of COVID-19 vaccine received receipt of an influenza vaccine, receiving influenza and COVID-19 vaccines on the same day, and the time between the reminder message and COVID-19 vaccination.
The study is designed to reflect real-world clinical practice. Participants will continue to receive routine medical care, and all vaccines will be provided through standard care processes. Researchers will compare vaccination outcomes across the different message groups to determine which communication approach is most effective for increasing vaccination uptake among high-risk adults.
This study may help health care systems better understand how to communicate with patients about vaccine options and improve vaccination coverage among populations at increased risk for severe COVID-19 illness.
- Conditions
- Covid-19 Vaccination
- Being tested
- Vaccine choice message, Vaccine choice + platform-framed message, Vaccine choice + HCP trust-framed message, Vaccine choice + reactogenicity-framed message
- Keywords
- COVID-19 Vaccination, COVID-19 Vaccine Uptake, Vaccine Choice, Behavioral Intervention, High-Risk Adults, Patient Preference, Pragmatic Trial, Implementation Science, Health Services Research
- Medical subject headings
- Patient Preference
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Vaccine choice messageBehavioural
A message communicating available choices of COVID-19 vaccines.
Vaccine choice + platform-framed messageBehavioural
A message communicating available choices of COVID-19 vaccines and differences in vaccine composition and mechanisms of protection by vaccine type.
Vaccine choice + HCP trust-framed messageBehavioural
A message communicating available choices of COVID-19 vaccines and emphasizes the support of healthcare personnel (HCP) for both vaccine options.
Vaccine choice + reactogenicity-framed messageBehavioural
A message communicating available choices of COVID-19 vaccines and expected side effects of available vaccines.
| Study group | Role | What they receive |
|---|---|---|
| Usual Care | No intervention | Standard COVID-19 vaccination reminder message sent as part of usual care. |
| A. Choice-framed | Experimental | Intervention arm tests the effects of choice-framed communication to increase patient's awareness of their available choices of COVID-19 vaccines, compared with usual care. Receives: Behavioral: Vaccine choice message |
| B. Choice + vaccine platform-framed | Experimental | Intervention arm tests the effects of choice-framed communication to increase patients' awareness of their available choices of COVID-19 vaccines AND explain differences in vaccine composition and mechanisms of protection by vaccine type, compared with usual care. Receives: Behavioral: Vaccine choice + platform-framed message |
| C. Choice + HCP trust-framed | Experimental | Intervention arm tests the effects of choice-framed communication to increase patients' awareness of their available choices of COVID-19 vaccines AND emphasizes the support of healthcare personnel (HCP) for both vaccine options, compared with usual care. Receives: Behavioral: Vaccine choice + HCP trust-framed message |
| D. Choice + reactogenicity-framed | Experimental | Intervention arm tests the effects of choice-framed communication to increase patients' awareness of their available choices of COVID-19 vaccines AND information about expected side effects, compared with usual care. Receives: Behavioral: Vaccine choice + reactogenicity-framed message |
What is being measured
The primary outcome is the main question the study is designed to answer.
Proportion of participants with documented receipt of the updated 2026-27 COVID-19 vaccine
Kaiser Permanente Southern California's electronic health record tracks the type of vaccine, dose, and date each patient receives. Immunization data will be retrieved from participants' electronic health records to ascertain COVID-19 immunization status during the study period.
Measured: up to 4 months after intervention
Secondary outcomes (4)
Type of COVID-19 vaccine received
The brand of COVID-19 vaccines received will be retrieved from participants' electronic health records to ascertain the type of COVID-19 immunizations received during the study period.
Measured: up to 4 months after intervention
Receipt of the 2026-27 influenza vaccine
Influenza vaccines received will be retrieved from participants' electronic health records to ascertain influenza immunization status during the study period.
Measured: up to 4 months after intervention
Co-administration of COVID-19 vaccine and influenza vaccine
The date of influenza and COVID-19 vaccines received will be retrieved from participants' electronic health records and used to ascertain the number of participants who received an influenza and COVID-19 vaccine on the same day.
Measured: up to 4 months after intervention
Time to immunization (in days) with an updated 2026-27 COVID-19 vaccine
The date of COVID-19 immunization will be retrieved from the participants' electronic health records and used to determine the number of days between message transmission and vaccination.
Measured: up to 4 months after intervention
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted24 Sep 2026
- Study start29 Sep 2026
- Primary completion31 Jan 2027 (estimated)
- Study completion30 Jun 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Covid-19 VaccinationStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Health services research
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Triple blind
- Who is masked
- Care provider, Investigator, Outcomes assessor
- Enrolment
- 1,300,000 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Kaiser Permanente
- Sponsor type
- University, hospital or other
- Collaborators
- Sanofi
- Responsible party
- Sponsor
- Investigators
- Annette Regan, PhD, Principal investigator, Kaiser Permanente
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07838038
- Sponsor's protocol ID
- 14603
- Other IDs
- IRB Number 14603
- Acronym
- EMPOWeR
- Status last verified
- Sep 2026
- First submitted
- 15 Sep 2026
- Last updated
- 15 Oct 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No: The individual-level data that will be analyzed for this study will not be publicly available due to privacy concerns. Individual requests to access the study data can be made to the study PI.