The Institutional Review Boards approved study procedures at both participating sites.

Providers were transparent about only having a basic knowledge of the Early Intervention Service referral process beyond their role in the initial referral. They recognized the need for a better follow up system by which they could track whether families were successfully connected to services.

Another provider had a general understanding of how the program is meant to operate but was unsure of how the process looks beyond the initial screening.

The medical providers recruited for the Memphis study site work predominantly in a hematology setting. Along with confusion regarding the process for EI services, some providers expressed concern regarding their knowledge of development and their ability to identify smaller delays due to their specialized training and experience. One provider noted that the delays she identifies are usually marked as serious delays.

Hematology practitioners report preferring primary care pediatricians (PCP) to survey for developmental delays and learning difficulties for this reason. PCPs monitor developmental milestones as part of regular checkups, so specialty practitioners feel it may be more efficient to have PCPs be the driver of identifying developmental delays and referring to EI services. In contrast, Hematologists do not give full developmental evaluations in their appointments, contributing to minor delays going unnoticed.

Furthermore, hematology practitioners' focus is ensuring the child's SCD is well-managed and developmental delays are outside of their scope.

Hematology practitioners' thoughts regarding who should drive identifying developmental delays were supported by primary care physicians (PCPs) interviewed in the St. Louis catchment area. PCPs reported conducting developmental surveillance regularly at wellness visits using measures such as the Ages and Stages questionnaire and the Modified Checklist for Autism in Toddlers.

PCPs had greater awareness of early intervention services and reported regularly referring children to services when they identified a developmental concern.

PCPs emphasized the importance of children with SCD attending their regularly scheduled well-child visits and hematology visits. They acknowledged the differing, yet essential, roles of hematologists and PCPs in providing care for patients with sickle cell disease.

While PCPs are more familiar with the process of obtaining EI services than hematology practitioners, they report a lack of follow-up from EI coordinators.

While medical providers reported a lack of familiarity with EI services, EI providers discussed lacking knowledge about SCD and the associated delays. All EI providers we spoke to discussed having very little formal education about sickle cell disease.

In addition to lack of formal training about SCD, EI providers discussed having limited experience providing services to children with SCD.

EI providers expressed an interest in additional education and training, such as a continuing education course, to address this gap in knowledge and experience so they can better serve children with SCD.

Medical and EI providers indicated a need to improve knowledge and education around SCD and EI services from differing perspectives. Medical providers would benefit from information regarding when to refer to EI services and the post-referral process. EI providers would welcome educational opportunities on SCD to serve those children and families better.

Medical providers identified barriers to getting young children with SCD connected to EI services. Barriers included socioeconomic hardships for families, a lack of community resources to address developmental concerns, and inconsistent screening practices for developmental delays.

Regarding socioeconomic status (SES), medical providers acknowledged the obstacles that families with fewer financial resources navigate to get their child to medical visits. EI services are difficult to prioritize for families struggling with basic needs.

Providers discussed transportation as a barrier to services in addition to competing family needs. Multiple providers discussed the benefit of EI services potentially being in the home; an option that would eliminate transportation needs but would still require caregivers to take time off work. One provider suggested home appointments take place outside of traditional working hours to reduce the amount of time caregivers miss work.

Hematology providers expressed frustrations regarding inconsistent screening for developmental delays. They wanted a brief screening tool more suitable for children with SCD that they could administer in their clinics as well.

This provider felt that this could address an additional barrier of long wait time to get SCD patients seen by psychologists or other developmental specialists.

Long wait times were also discussed due to not having enough EI providers in the community. This was particularly a concern for providers in Tennessee, where SCD was recently added to the list of conditions that automatically qualifies a child for EI services. Although automatic qualification for EI services will improve access for patients with SCD, there may not be enough providers to meet the needs of Tennessee communities.

Some EI providers expressed similar concerns about EI resources in the community, particularly a finite number of EI providers. EI providers complete intervention visits in the families' homes. Some providers who were predominantly in rural communities may travel up to 2 h between visits, which takes away from the number of children they can treat.

Another barrier identified by EI providers is the lack of EI awareness in the medical community. As noted in the education section, medical providers often lack understanding of EI services and may only refer for major delays. EI providers reported this as being a major barrier to getting children into services, as medical providers are the primary gatekeepers to obtaining additional services.

PCPs see patients at a higher frequency and are in a better position to identify delays and when a child needs services. While families can access services without a referral from a physician, ensuring that pediatricians are aware of EI services and when to refer children is an essential step towards addressing this barrier.

This barrier is further exacerbated by families residing in rural areas, who may not see a pediatrician but a family medicine doctor. Family medicine physicians have less specialized training in developmental milestones and are even less likely to refer children to EI services due to lack of identification.

In addition to medical providers' lack of awareness of EI programming, families being unaware of EI services hinders access to services. EI providers specifically discussed families needing to know that these services exist and that the services primarily occur in the families' homes.

Families of children with SCD often must travel to multiple medical appointments and are uneasy about adding an additional clinic visit to their schedule. Home visits reduce the burden of lack of transportation.

It can be difficult to get a physician to refer for a developmental delay, and many families do not know they do not need a physician referral to be evaluated for EI. However, they do need a referral or an evaluation to get into services.

Increasing awareness around the various avenues to obtain EI services will empower families to help their children access care. It is important to improve families' knowledge of developmental milestones in tandem, so they are familiar with both how to obtain services and when services are needed.

EI providers expressed similar concerns regarding SES and resources hampering families' access to EI services. Although EI services take place in the home, transportation was still cited as a barrier to accessing EI services, particularly for families in rural communities. Lower income families are less likely to travel over an hour to a city with pediatric providers.

As previously noted, family medicine providers are not as skilled at identifying developmental delays and referring to services, and walk-in clinics are not screening for developmental delays. When families do overcome the issue of being referred to and obtaining services, some caregivers struggle to be available for the home visits. Caregivers may not be able to take time off from work. Others may be navigating their own chronic illness or mental health condition.

Medical and EI providers had overlapping concerns regarding barriers to accessing socioeconomic status, albeit from different perspectives. SES was frequently noted as a major factor for families’ inability to utilize EI resources. In addition to SES, both providers expressed the lack of EI services in the community contributes to difficulty obtaining services.

Communication and linkages among institutions (e.g., general pediatricians, EI providers, hematology teams) need to improve to better serve children with SCD who need EI services.

Medical providers worry that some children get lost in the process due to this lack of communication between medical providers and EI providers. Building networks among pediatricians, hematology practitioners, EI providers and the community is necessary to prevent families from falling through the cracks.

One provider suggested including developmental screening and EI services in the electronic medical record. Other medical processes have automatic triggers in the medical record to order consults or medications. It may be beneficial to have triggers for developmental evaluations or other EI services built into medical record systems for children with SCD.

In addition to communicating across professions, medical providers need to communicate the importance of developmental services for children with SCD to caregivers in a manner that builds trust.

The trust component is essential to these conversations, as some caregivers might not be ready to accept their child might benefit from EI services.

EI providers expressed concerns that caregivers of children with SCD may not have the information needed to navigate the medical and EI systems and that current methods of providing information are not sufficient to help parents understand EI services. One provider explained the importance of conversing with caregivers to ensure their understanding of the EI referral process.

One provider mentioned meeting families where they are and tailoring information to each family to ensure they understand.

Families can be overwhelmed or scared when learning about potential developmental delays for their child. EI providers discussed the importance of empowering families to understand their role in helping their child improve.

Both medical providers and EI providers acknowledged a need for improved communication with caregivers. Medical providers spoke of their role in motivating parents to seek treatment by effectively communicating the importance of early intervention, while E.I. providers suggested ways to empower families to navigate the E.I. system. Medical providers also stressed the need for better communication between providers to improve efficiency.

Patients with SCD are at high risk for developing developmental delays that worsen as they grow older. EI services early in life can limit these delays and improve long-term outcomes, yet most families of young children with SCD do not utilize these services. Semi-structured interviews with medical and EI providers identified three broad themes that influenced EI utilization: Awareness, Access, and Communication. These themes highlight numerous gaps that facilitate the testing of targeted solutions to increase EI utilization among this vulnerable population, such as (1) increasing provider education (e.g., handouts or didactics on SCD for EI providers), (2) improving access to services (e.g., via virtual/telehealth options), and (3) improved communication between providers (e.g., via patient navigator). Further research is needed to explore the feasibility and efficacy of these potential solutions.

The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.

The studies were approved by Institutional Review Boards at St. Jude Children's Research Hospital and Washington University in St. Louis. The studies were conducted in accordance with the local legislation and institutional requirements. The participants provided their informed consent to participate in this study.

AH: Conceptualization, Funding acquisition, Investigation, Methodology, Supervision, Writing – original draft, Writing – review & editing. EM: Conceptualization, Data curation, Formal Analysis, Project administration, Validation, Writing – original draft, Writing – review & editing. MT: Conceptualization, Data curation, Formal Analysis, Project administration, Validation, Writing – original draft, Writing – review & editing. AW: Data curation, Formal Analysis, Writing – original draft, Writing – review & editing. JH: Conceptualization, Methodology, Supervision, Writing – original draft, Writing – review & editing. CH: Conceptualization, Funding acquisition, Investigation, Methodology, Resources, Supervision, Writing – original draft, Writing – review & editing.

The author(s) declare that financial support was received for the research, authorship, and/or publication of this article.

This work was supported by the American Lebanese Syrian Associated Charities (ALSAC). AH was supported by K23HL166697 (National Heart, Lung, and Blood Institute) during the time of this study. CH was supported by K23HL161328 (National Heart, Lung and Blood Institute) during the time of this study. CH and AH were supported by the Implementation Science Collaborative between Washington University and St. Jude Children's Research Hospital. This publication was supported by the NIH/National Center for Advancing Translational Sciences (NCATS) grant UL1TR002345 to CH (CTSA1505).

The authors thank the providers for their study participation.

AH received consultancy fees from Global Blood Therapeutics.

The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.