Study Aim: To (a) assess acceptability, appropriateness, and feasibility of the digital
storytelling (DST) intervention, and (b) estimate a pilot effect size of the
intervention, via a Pragmatic Trial in 2 clinics in historically Black neighborhoods.
Overview: A pilot pragmatic trial of a DST intervention in caregivers of children 6 mo.
to 5 yrs. (n = 200) receiving care at two clinics in historically Black neighborhoods in
Denver, CO during one influenza season (10/1/24-3/30/25), assessing pragmatic outcomes
and pilot effectiveness with mixed methods.
Setting & Design: The investigators will pilot the intervention at 2 Denver Health
primary care clinics in historically Black neighborhoods. These clinics serve >3,000
empaneled Black children and provided >6,000 influenza vaccines to children in 2020-21.
Caregivers will be eligible if their child is empaneled (i.e., had 1 well child visit in
last 18 months), will be 6 months to 5 years old during the upcoming influenza season
(10/1 to 3/30), and has no medical contraindications to vaccination. The investigators
will exclude caregivers whose first language is not English, as digital stories will be
narrated in English, or are younger than 18 years. A research assistant will recruit
caregiver-child dyads from May 1, 2024 to September 30, 2024 in clinic waiting rooms.
Caregivers will complete a survey with demographic and vaccine hesitancy items and
provide their cell phone number and e-mail address for intervention purposes.
Intervention Description: While this work is highly emergent in nature and exact
implementation details are subject to stakeholder refinement, the investigators
anticipate the following structure. On October 1st, dyads will be randomized to
intervention or control groups (1:1 ratio). Intervention caregivers will receive a series
of 6 monthly texts with embedded digital stories and accompanying health messaging.
Control caregivers will receive usual care.
Outcomes: Our primary aim will be child influenza vaccination status, extracted from our
electronic health record (EHR) at season's end (March 30, 2025). Caregivers assigned to
the intervention group (n = 100) will receive a follow-up survey with validated measures
assessing their perceptions of intervention feasibility, acceptability, and
appropriateness.
Covariates: Caregiver independent variables will include age, sex (as a biological
variable), education, income, race, ethnicity, insurance status, and scaled vaccine
hesitancy score (range: 0-100, with 0 indicating not at all hesitant). The investigators
will assess caregivers' perceptions of DST feasibility, appropriateness, and
acceptability with validated questions on a 5-point Likert scale, which read at a 5th
grade level. Child-level variables will include age, sex (as a biological variable),
race, and ethnicity. To estimate pilot effectiveness for future power calculations, our
primary outcome will be child vaccination status at season's end (March 30th), defined in
a binary manner (receipt of ≥ 1 dose by season's end versus unvaccinated). The
investigators chose this definition as our pilot data found parental vaccine hesitancy
increased a child's risk of influenza non-vaccination but did not increase their risk of
partial vaccination (vs. full).
Analyses, Sample Size, & Calculations: The investigators will calculate descriptive
statistics of caregivers' demographics and vaccine hesitancy scores. For our primary
outcome of pilot effectiveness, the investigators will use an intention-to-treat approach
comparing the proportion of children of caregivers randomized to digital stories versus
literacy videos who received 1 or more vaccine dose by season's end. The investigators
will fit univariable and multivariable logistic regression models to explore associations
with caregiver demographics and parental vaccine hesitancy scores. To address instances
of video non-viewing, the investigators will repeat these analyses between caregivers
whose unique Digital Story links were accessed - i.e., presumably viewed - and caregivers
in the control group.
The investigators will then describe intervention caregivers' perceptions of feasibility,
acceptability, and appropriateness; as set cut points for acceptability and
appropriateness do not yet exist, the investigators plan to use ≥ 70% agreement as with
prior work by our group. Using these cut points, the investigators will fit univariable
and multivariable logistic regression models to estimate the association between
covariates (e.g., demographics, vaccine hesitancy score) and whether a caregiver
perceived the intervention as feasible, acceptable, or appropriate.
The investigators performed sample size calculations based on the precision with which
the investigators could estimate the treatment effect, as measured by the difference in
proportion vaccinating between intervention and control arms. The investigators
hypothesize our estimated pilot effect size will be ≥ 0.10, or modest for a vaccination
trial. With n = 200, the investigators expect to attain a margin of error (equal to one
half of the width of a 95% confidence interval) for the estimated treatment effect of
approximately 0.14). All analyses will be performed in R.
SA3.5. Limitations & Alternative Approaches: (1) Poor recruitment. The investigators
collected pilot data in the same clinic and 2 others from 255 caregivers of 2 year-olds
in 6 months. By extending inclusion criteria to ages 6 months to 5 years, the
investigators are confident the investigators can recruit 200 dyads. If necessary, the
work will continue during a second influenza season (10/1/2025 - 3/31/2026) to ensure the
investigators meet recruitment goals. (2) Poor perceived acceptability, appropriateness,
or feasibility. If our analyses suggest the investigators need to improve intervention
feasibility, acceptability, or appropriateness, the investigators will work with
community and clinical stakeholders to iteratively modify and pilot-test the adapted
intervention.