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Patient Portal Flu Vaccine Reminders_RCT 5 (LADHS)

Improving Influenza Vaccination Delivery Across a Health System by the Electronic Health Records Patient Portal RCT 5 (LADHS)

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT05535777
Acronym
LADHS
Enrollment
246295
Registered
2022-09-10
Start date
2022-09-13
Completion date
2023-03-31
Last updated
2025-04-11

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Influenza, Respiratory Tract Infections

Keywords

Reminder Recall (R/R), Influenza Vaccine, Electronic Health Record, Text Message, Vaccine

Brief summary

This trial is taking place in Los Angeles, CA at clinics within the Los Angeles Department of Health clinics. The study design is a comparative effectiveness trial design. Patients will be randomized into 1) receiving enhanced texting with a callback by a trained call-center staff member to schedule a vaccine visit if the patient presses 1 in response to the text, 2) receiving enhanced bidirectional texting with a texting response from a trained call-center staff member who will help the patient schedule a vaccine visit through a series of back-and-forth texts, or 3) standard text reminders (control group). Patients in all arms will receive reminders if they are due for influenza vaccine. Despite the Advisory Committee on Immunization Practices (ACIP) recommendation in 2010 that all people above 6 months of age should receive an annual flu vaccine, vaccination rates remain low: at 6m-4.9 yrs. (70%), 5-17.9 yrs. (56%), 18-64.9 yrs. (38%), and \>65 yrs. (63%). The investigators will assess the effectiveness of enhanced text R/R messages as compared to the standard of care control (standard text reminders).

Detailed description

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 do 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 text messaging at the health system level. This randomized controlled trial will assess the effectiveness of reminders messages sent by text encouraging influenza vaccination, on increasing influenza vaccination rates within a health system. Patients will be randomized into three groups: 1) one-third of patients will receive enhanced text reminder messages, 2) one-third will receive enhanced bidirectional text reminder messages and 3) one-third will received standard-of-care text reminder messages. Enhanced texts - Callback by a person: Patient randomized to this study arm will receive a phone call back by a call center agent if they press 1 in response to a question on the original text message. The call center agent's job is to schedule patients for clinical visits. These call center agents will be trained by our faculty and staff and will have the usual HIPAA and other patient confidentiality training. Enhanced Bidirectional Texts: These texts are designed to help schedule a vaccine visit. Patients randomized to this study arm will receive a text message from a call center agent if they press 1 in response to a question on the original text message. The bidirectional texts will have an agent who can answer questions and schedule an appointment through text message back-and-forth conversations with the patient. Bidirectional texts will be exchanged on a HIPAA compliant bidirectional text messaging platform. The patient will use the regular SMS function on their cellphone and the agent will receive and respond to the bidirectional text on the HIPAA compliant platform. Previous studies have shown that low-cost, behavioral nudges through texting can increase influenza vaccination uptake compared to usual care. However, there are limited studies that evaluate the effect of decreasing friction/barriers to scheduling especially within safety net populations. This study will examine the effect of strategies to reduce friction/barriers to scheduling including bidirectional text messages, and texts for patients to call for direct scheduling without wait time on influenza vaccination rates in adults within the 2022-2023 flu season. For the primary analysis, the primary outcome will be the patient's end of flu season vaccination status. Intervention effects will be assessed using multivariable log-binomial regression models. Regressions will include indicators for each intervention as fixed effects, with the standard text condition as the reference group, and potentially clinic random effects, depending on retrospective analysis results. Models will also adjust for patient age, gender, race/ethnicity, insurance, and whether the patient was vaccinated in at least one of the prior two flu seasons. The enhanced texts with callback, enhanced bidirectional texts, and standard-of-care text reminder messages will begin in September of 2022.

Interventions

BEHAVIORALEnhanced texts with Callback by a Person

Enhanced texts - Callback by a person: Patient randomized to this study arm will receive a phone call back by a call center agent if they press 1 in response to a question on the original text message. The call center agent's job is to schedule patients for clinical visits. These call center agents will be trained by our faculty and staff and will have the usual HIPAA and other patient confidentiality training.

BEHAVIORALEnhanced Bidirectional Texts

Patients randomized to this study arm will receive a text message from a call center agent if they press 1 in response to a question on the original text message. The bidirectional texts will have an agent who can answer questions and schedule an appointment through text message back-and-forth conversations with the patient.

Sponsors

National Institute of Allergy and Infectious Diseases (NIAID)
CollaboratorNIH
Los Angeles County Department of Public Health
CollaboratorOTHER_GOV
University of California, Los Angeles
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
HEALTH_SERVICES_RESEARCH
Masking
SINGLE (Subject)

Intervention model description

Pragmatic comparative effectiveness trial with a standard-of-care control group

Eligibility

Sex/Gender
ALL
Age
6 Months to No maximum
Healthy volunteers
No

Inclusion criteria

* LADHS patients identified as primary care patients assigned as follows: (1) assigned through managed care plans, (2) self-pay but linked with a provider, or (3) uninsured but assigned.

Exclusion criteria

* LADHS patient not identified as a primary care patient.

Design outcomes

Primary

MeasureTime frameDescription
Receipt of the Annual Influenza Vaccine Among Adult and Pediatric Index Patients6 monthsPercent of patients with annual influenza vaccination (between 9/1/22 - 4/1/23) among adult and pediatric index patients. Outcomes will be assessed via vaccine data extraction from the electronic health record and external claims and pharmacy data. The index patients must be an LADHS patient. Primary care patients who are empaneled to a primary care provider within DHS are assigned as follows: (1) assigned through managed care plans, (2) self-pay but linked with a provider or (3) uninsured but assigned). Individuals not affiliated with any primary care practice will be excluded from the primary analysis.

Secondary

MeasureTime frameDescription
Receipt of the Annual Influenza Vaccine Among Pediatric Index Patients6 monthsPercent of patients with annual influenza vaccination (between 9/1/22 - 4/1/23) among pediatric index patients. Outcomes will be assessed via vaccine data extraction from the electronic health record and external claims and pharmacy data. The index patients must be an LADHS patient. Primary care patients who are empaneled to a primary care provider within DHS are assigned as follows: (1) assigned through managed care plans, (2) self-pay but linked with a provider or (3) uninsured but assigned). Individuals not affiliated with any primary care practice will be excluded from the primary analysis.

Countries

United States

Participant flow

Participants by arm

ArmCount
Enhanced Text Reminders With Callback by Person
Participants in this arm will receive up to 3 R/R messages by text. R/R message will receive a phone call back by a call center agent if they press 1 in response to a question on the original text message. The call center agent's job is to schedule patients for clinical visits. These call center agents will be trained by our faculty and staff and will have the usual HIPAA and other patient confidentiality training. Enhanced texts with Callback by a Person: Enhanced texts - Callback by a person: Patient randomized to this study arm will receive a phone call back by a call center agent if they press 1 in response to a question on the original text message. The call center agent's job is to schedule patients for clinical visits. These call center agents will be trained by our faculty and staff and will have the usual HIPAA and other patient confidentiality training.
6,914
Enhanced Bidirectional Text Reminders
Participants in this arm will receive a text message from a call center agent if they press 1 in response to a question on the original text message. The bidirectional texts will have an agent who can answer questions and schedule an appointment through text message back-and-forth conversations with the patient. Bidirectional texts will be exchanged on a HIPAA compliant bidirectional text messaging platform. The patient will use the regular SMS function on their cellphone and the agent will receive and respond to the bidirectional text on the HIPAA compliant platform. Enhanced Bidirectional Texts: Patients randomized to this study arm will receive a text message from a call center agent if they press 1 in response to a question on the original text message. The bidirectional texts will have an agent who can answer questions and schedule an appointment through text message back-and-forth conversations with the patient.
6,901
Standard Text Reminders
Participants in this arm will receive up to 3 text messages, reminding them about the importance of influenza vaccination. The standard texts will include a clinic call back number and patient portal self-scheduling for patients to schedule their influenza vaccines. The direct scheduling texts includes a direct number to an agent that can help schedule and answer questions on the phone in real time. The texts with a direct number to schedule will link a specified phone number to call and schedule. This number would be answered by a central agent quickly and a patient could schedule their flu shot at any clinic site. This specific phone number would not go through the multiple option menus a patient would normally experience when calling their clinic.
180,423
Total194,238

Baseline characteristics

CharacteristicEnhanced Bidirectional Text RemindersStandard Text RemindersEnhanced Text Reminders With Callback by PersonTotal
Age, Customized
6 months+
6901 Participants180423 Participants6914 Participants194238 Participants
Primary Language
English
3588 Participants94207 Participants3656 Participants101451 Participants
Primary Language
Missing
323 Participants8626 Participants301 Participants9250 Participants
Primary Language
Other
231 Participants5669 Participants214 Participants6114 Participants
Primary Language
Spanish
2759 Participants71921 Participants2743 Participants77423 Participants
Race/Ethnicity, Customized
American Indian or Alaska Native
8 Participants216 Participants8 Participants232 Participants
Race/Ethnicity, Customized
Asian
383 Participants9773 Participants415 Participants10571 Participants
Race/Ethnicity, Customized
Black or African American
729 Participants19092 Participants764 Participants20585 Participants
Race/Ethnicity, Customized
Hispanic/Latino
4135 Participants108204 Participants4089 Participants116428 Participants
Race/Ethnicity, Customized
Missing
241 Participants6323 Participants220 Participants6784 Participants
Race/Ethnicity, Customized
Multi-Race
37 Participants1166 Participants45 Participants1248 Participants
Race/Ethnicity, Customized
Native Hawaiian or Other Pacific Islander
9 Participants279 Participants15 Participants303 Participants
Race/Ethnicity, Customized
Other/Unknown
1061 Participants27213 Participants1066 Participants29340 Participants
Race/Ethnicity, Customized
White
298 Participants8157 Participants292 Participants8747 Participants
Sex/Gender, Customized
Female
3638 Participants96646 Participants3763 Participants104047 Participants
Sex/Gender, Customized
Gender unknown
1 Participants36 Participants3 Participants40 Participants
Sex/Gender, Customized
Gender unspecified
1 Participants46 Participants1 Participants48 Participants
Sex/Gender, Customized
Male
3020 Participants77372 Participants2927 Participants83319 Participants
Sex/Gender, Customized
Missing
241 Participants6323 Participants220 Participants6784 Participants
Vaccination in Prior Season
False
5629 Participants147375 Participants5678 Participants158682 Participants
Vaccination in Prior Season
True
1272 Participants33048 Participants1236 Participants35556 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
EG002
affected / at risk
deaths
Total, all-cause mortality
0 / 00 / 00 / 0
other
Total, other adverse events
0 / 00 / 00 / 0
serious
Total, serious adverse events
0 / 00 / 00 / 0

Outcome results

Primary

Receipt of the Annual Influenza Vaccine Among Adult and Pediatric Index Patients

Percent of patients with annual influenza vaccination (between 9/1/22 - 4/1/23) among adult and pediatric index patients. Outcomes will be assessed via vaccine data extraction from the electronic health record and external claims and pharmacy data. The index patients must be an LADHS patient. Primary care patients who are empaneled to a primary care provider within DHS are assigned as follows: (1) assigned through managed care plans, (2) self-pay but linked with a provider or (3) uninsured but assigned). Individuals not affiliated with any primary care practice will be excluded from the primary analysis.

Time frame: 6 months

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Enhanced Text Reminders With Callback by PersonReceipt of the Annual Influenza Vaccine Among Adult and Pediatric Index Patients4641 Participants
Enhanced Bidirectional Text RemindersReceipt of the Annual Influenza Vaccine Among Adult and Pediatric Index Patients4629 Participants
Standard Text RemindersReceipt of the Annual Influenza Vaccine Among Adult and Pediatric Index Patients120137 Participants
Secondary

Receipt of the Annual Influenza Vaccine Among Pediatric Index Patients

Percent of patients with annual influenza vaccination (between 9/1/22 - 4/1/23) among pediatric index patients. Outcomes will be assessed via vaccine data extraction from the electronic health record and external claims and pharmacy data. The index patients must be an LADHS patient. Primary care patients who are empaneled to a primary care provider within DHS are assigned as follows: (1) assigned through managed care plans, (2) self-pay but linked with a provider or (3) uninsured but assigned). Individuals not affiliated with any primary care practice will be excluded from the primary analysis.

Time frame: 6 months

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026