Explanation for the choice of comparators {6b}
The trial intervention will be the STAR model, which consists of (1) enhanced school hearing screening, (2) school-based specialty telehealth follow-up, and (3) streamlined communication between schools, healthcare providers, and parents/caregivers. This intervention was designed based on evidence from our prior trial in Northwest Alaska, which provided critical proof of concept that telehealth can improve follow-up after school hearing screening [25]. Because of the strong recommendation from the mixed methods component of the prior trial to bring telehealth technology into the school setting [19], this trial will evaluate the use of school-based specialty telehealth follow-up among children who receive a referral from school hearing screening (intervention) compared with the traditional referral, which is a letter home to parents advising follow-up (control) (Fig. 4).
Comparison of follow-up pathways following school hearing screening
Data for the first two rows provided from our prior trial in northwest Alaska
The enhanced hearing screening component, also developed based on our prior trial, is not randomized since it is based on established evidence. The enhanced hearing screening that will be implemented in all participating schools consists of a hearing assessment combined with tympanometry, a middle ear assessment that is essential for identifying preventable, infection-related hearing loss. Based on our prior data, children 7 years and older will receive pure-tone screening, while children 6 years and younger will receive otoacoustic emissions (OAE) screening. All children will receive tympanometry to assess middle ear health [27]. The STAR enhanced hearing screening protocol differs from the screenings currently being done in Alaska. The state mandates school hearing screening, but protocols vary across school districts and do not include tympanometry [37].
-
Pure-tone screening: will include screening at 1, 2, 4, and 6 kHz at 15 dB. Frequencies were selected based on evidence from our prior trial in Alaska [27], and the 15 dB screening level was selected to align with the new World Health Organization definition of hearing loss [38]. A tone will be presented at each frequency to each ear. If a child does not respond to a tone, a second tone will be played. Failure to respond to any tone twice at any frequency in either ear will generate a referral [39].
-
OAE screening: will include screening at 2, 3, 4, and 5 kHz, with a 3 of 4 frequency pass criteria [40].
-
Tympanometry screening: Type B (flat) tympanogram or negative pressure less than −200 decapascal (daPa) will generate a referral per standard clinical guidance [41].
The communication component between schools, healthcare providers, and parents/caregivers will be developed during the systematic adaptation of the STAR model in Aim 1 and rolled out with specialty telehealth follow-up.
Intervention description {11a}
The trial will evaluate the effectiveness of school-based specialty telehealth follow-up. Enhanced hearing screening and specialty telehealth follow-up will be designed to use a single unified platform. It will include tools for initial screenings (OAE, tympanometry, and pure-tone screening), as well as a digital otoscope. Results will be transmitted asynchronously to an audiologist, who will determine the recommended plan of care. This process will be conducted onsite at the school. Parents will be notified that the specialty telehealth follow-up is occurring but will not be required to attend, based on community feedback in our prior trial [21, 29].
Criteria for discontinuing or modifying allocated interventions {11b}
This study entails minimal risk, and adverse events are not expected. Participant involvement includes a one-time enhanced hearing screening that will take about 5–10 min, and for children who receive a referral from screening, a one-time, 15–20-min session to collect ear and hearing information for specialty telehealth follow-up. We do not expect discontinuation from the specialty telehealth follow-up intervention; however, if a parent/caregiver chooses to withdraw their child from the study, we will stop all study-related activities not yet completed.
Strategies to improve adherence to interventions {11c}
We will develop training materials and an implementation plan for the STAR model during Aim 1. Throughout the trial, we will track fidelity to the implementation plan, as well as adaptations. These measurements will be taken annually, as part of the implementation evaluation activities. To reduce burden on school staff conducting the screenings, fidelity will primarily be assessed by the research team using a structured fidelity checklist, which will be developed to align with the implementation plan. Checklist data will be analyzed as part of the mixed methods evaluation for Aim 2b.
Relevant concomitant care permitted or prohibited during the trial {11 d}
As a pragmatic trial, we will not prohibit concomitant care. Parents and their children will be permitted to seek their own hearing care and arrange for follow-up or other interventions as they choose.
Provisions for post-trial care {30}
N/A. This trial specifically addresses follow-up immediately after school hearing screening and not subsequent care.
Outcomes {12}
The primary effectiveness outcome will be the proportion of referred children (i.e., those who failed screening) who receive specialty follow-up within 60 days of the screening date. Secondary implementation outcomes include fidelity, reach, acceptability, appropriateness, and feasibility. An additional secondary outcome will be sustainability. Outcome details are included in Table 1.
Participant timeline {13}
The timeline for the trial is detailed in Fig. 2 and Table 2. Broadly, the formative phase to adapt the STAR model (Aim 1) will be conducted during Years 1–2. The enhanced hearing screening portion of the STAR model will be implemented in all participating schools in Year 3, and Year 3 will serve as baseline data for the stepped wedge, cluster randomized trial (Aim 2a). Specialty telehealth follow-up will be implemented in a phased fashion during Years 4 and 5 based on sequence randomization. The implementation evaluation (Aim 2b) will be conducted annually in Years 3–5, and the sustainability evaluation (Aim 3) will occur over the same timeframe.
Sample size {14}
The stepped-wedge cluster randomized trial will be conducted in approximately 25 schools located in 3 regions of rural Alaska. For power calculations, we used enrollment numbers from school districts in 3 regions representative of the regions that will be considered for inclusion in the trial. These 3 regions serve a combined total of approximately 2072 students per year in grades that perform hearing screening, with a median of 99 students per school per year.
The study design is open cohort; however, in practice, we expect it to more closely resemble a repeated cross-sectional design because we expect most data to be collected from different children in each year of the study due to existing school protocols of not screening every grade. Therefore, for the purposes of calculation of power we conservatively assumed a repeated cross-sectional stepped wedge design with a binary outcome. To do so, we used the approach from Hemming et al. based on a comparison of two proportions [44], incorporating design effects to account for clustering by school, repeated measures on the same cluster and t-based inference to accommodate the small number of clusters (i.e., 25 schools).
To calculate the expected cluster size for the primary outcome, it was necessary to estimate the number of referred students for each year in each school. To do this, we multiplied an assumed school-level screening rate of 90% (based on experience from our prior trial) by the 2020–2021 school-level enrollment in grades that perform hearing screening (based on local knowledge of previous screening protocols in each region) and by an expected referral rate of 15%. The expected 15% referral rate was based on historical, regionwide referral rates from the 2020–2021 and 2021–2022 school years. Estimated cluster sizes were then rounded down to the nearest whole number to obtain the final expected cluster size for the primary outcome (Fig. 5). Enrollment counts in eligible grades in each region were also used to estimate the coefficient of variation (CV) of cluster size to generate appropriately conservative power estimates accounting for variation in cluster size.
Estimating cluster size for primary effectiveness outcome based on prior school data
1Based on 2020–2021 enrollment data, assume similar enrollment level across all cluster periods and the following screening practices: Region 1 screens K-5; Regions 2 and 3 screen K, 1, 3, 5, 7, 10. 2Based on school enrollment, assumed screening rate of 90%, and assumed referral rate of 15%, 3 schools are expected to have zero referred children
Using an expected referral rate of 15%, estimation of median cluster size revealed that 3 of the smaller schools may have zero referrals. Among the remaining 22 of 25 schools that are expected to have referrals, we anticipate a median cluster size of 14 referred children and a CV of cluster size of 0.59. For simplicity, we also assumed an equal number of schools per sequence (11 schools). Regarding the rationale for our assumed proportion of referrals resulting in specialty telehealth follow-up within 2 months, we note that in our prior trial we observed a 42.2% percentage point difference in the number of children seen for specialty follow-up within 60 days of screening [25, 28]. To be conservative, we assumed the proportion with specialty follow-up to be 20% for children in the control condition and an expected 40 percentage point difference in follow-up between treatment and control conditions. We estimated a within-period intracluster correlation (ICC) of 0.30, based on the results of our prior trial and conservatively assumed a cluster autocorrelation (CAC) of 0.7 with a two-period decay (i.e., nested exchangeable) structure between measurements within the same cluster over subsequent time periods. We assume a two-period decay structure in the design phase rather than an alternate less realistic structure such as exchangeability to protect against an underpowered trial [45, 46]. With these assumptions, and an alpha of 0.05, the trial will have greater than 90% power to detect an increase of at least 40 percentage points in the proportion of referred children receiving specialty follow-up (comparable to the 42-percentage point difference seen during the prior trial) [46,47,48]. Power calculations, based on the assumptions described above, were performed using the web app, “The Shiny CRT Calculator: Power and Sample Size for Cluster Randomised Trials” (https://clusterrcts.shinyapps.io/rshinyapp/).
A sensitivity analysis was performed to assess the effect of changes in assumptions for referral rate, within-period ICC, and cluster autocorrelation (CAC) on power for the primary outcome analysis (Fig. 6). Using 80% power as minimum target power (and 90% as preferred power level), the plots show acceptable power in all scenarios.
Sensitivity analysis for primary effectiveness outcome
Assumptions: screening rate: 90%; control follow-up rate: 20%; intervention follow-up rate: 60%. Screening K-5 in Region 1; Screening K, 1, 3, 5, 7, 10 in Regions 2 and 3. Number of clusters, median cluster size, and CV of cluster size dependent on referral rate
Recruitment {15}
Participants in Aim 1 will include educational staff, healthcare providers, parents, and children in the three regions participating in the study. The number of participants to be recruited will be based on the dual goal of reaching saturation and achieving representation of several different types of educational staff and healthcare providers, different regions, and different school sizes. Potential participants will be identified using purposeful and/or snowball sampling. Recruitment outreach will occur via email, flyers, presentations, and/or in-person, as appropriate. Informed consent procedures and study enrollment will be conducted by trained research staff. Children must have a parent/caregiver provide informed consent for a child to participate. In addition, children aged 7 to 17 years will be required to sign a child assent form. It is unlikely that a child under age 7 will participate. However, should a child younger than 7 years wish to enroll, then a verbal assent will be used in combination with parent/guardian informed consent.
Leaders in the Alaska Department of Education and Early Development will provide guidance to the study team on potential school districts that might participate in the randomized trial (Aim 2a). The study team will engage with superintendents in these districts to gauge interest. In participating regions, all students enrolled in grades that the district typically screens for hearing will be eligible for hearing screenings. Per standard practice, parents may opt out of school hearing screenings if they prefer their child not to receive screening. All students who receive a school hearing screening referral will be eligible for specialty telehealth follow-up (Years 4–5), but parent/caregiver consent will be required. Consent forms for the specialty telehealth follow-up will be included in routine annual school paperwork, or in other mediums based on guidance by the Community Advisory Board (CAB) and community input obtained during Aim 1.
Participants in the STAR model, including school staff, healthcare providers, and parents, will be engaged in questionnaires and interviews to evaluate implementation (Aim 2b). These individuals will participate as partners instead of consented research participants. Study staff will use email, phone calls, or in-person interactions to invite these partners to contribute. A participant information sheet will be provided to partners that emphasizes the voluntary nature of their contribution.
Relevant policymakers, state leaders, decision-makers in state government in healthcare, healthcare financing, and education; leaders of Tribal community and healthcare entities; and leaders of regional or local organizations that work on rural healthcare delivery will be recruited to participate in the sustainability evaluation of STAR (Aim 3). The sampling frame and specific leaders contacted to participate will be established through guidance from regional leadership and the CAB. Leaders will be recruited to participate as partners instead of consented research participants. A participant information sheet will be provided to partners, which emphasizes the voluntary nature of their contribution.
We do not anticipate challenges with recruitment for the trial because data collection will occur at the population level, with entire schools participating. Individual consent will be obtained for the specialty telehealth follow-up intervention, and a community-informed implementation plan will be developed during the formative phase in Aim 1 to maximize uptake.
link