Psychotropic Medication Prescription Patterns in Down Syndrome in a Large Pediatric Specialty Clinic.

Objectives: Patterns of psychotropic medication use in children and adolescents with Down syndrome (DS) are largely unknown. Clinical decisions are often made from evidence and experience from individuals with autism spectrum disorder (ASD) or intellectual disability (ID). Methods: Longitudinal data from 670 children with DS who received care in a specialty DS clinic from March 2021 to February 2024 were collected. After each clinic visit, the clinician indicated the presence or absence of co-occurring neurodevelopmental (ND) or mental health (MH) diagnoses, as well as whether the individual was prescribed a psychopharmacological treatment. We used descriptive statistics and analyzed associations between psychotropic medication use, co-occurring ND/MH conditions, and demographic data. Results: 19.1% of patients were prescribed at least one psychotropic medication at their most recent clinical visit. Alpha-agonists were the most commonly prescribed medication class (30.8%), followed by stimulants (18.9%), and antidepressants (16.7%). There was a significant difference in psychotropic medication use by age, with older children having increased odds of being prescribed a psychotropic medication. There were no differences in psychotropic medication use across sex (p = 0.10), race (p = 0.10), or household income (p = 0.16). Conclusions: We found that one-fifth of patients with DS were prescribed psychotropic medications. Nearly every individual with DS who was prescribed a psychotropic medication had a co-occurring ND/MH condition, yet these rates were lower than what have been reported in children with ID, ASD, and attention deficit/hyperactivity disorder. Further research needs to include those with DS to further understand medication efficacy and safe dosing practices to ensure optimal outcomes.

The JASPER (Joint Attention, Symbolic Play, Engagement and Regulation) Intervention in Down Syndrome: A pilot study.

BACKGROUND: Children with Down syndrome (DS) often need support building language, socialization, and regulation, yet few receive behavioral intervention for this. The Joint Attention, Symbolic Play, Engagement and Regulation (JASPER) intervention holds promise as a clinician-caregiver-mediated approach. AIMS: The aims of this pilot study were to (1) describe the behavioral phenotype of children with DS (2) quantify change in child engagement following JASPER receipt, (3) measure caregiver adoption of JASPER strategies, and (4) generate hypotheses and directions for future research. METHODS AND PROCEDURES: Sixteen toddlers with DS and their caregivers enrolled in the study. Dyads were randomly assigned to one of two conditions: immediate intervention or waitlist control. During the COVID-19 pandemic, intervention was delivered remotely. OUTCOMES AND RESULTS: Caregivers learned to implement JASPER strategies and pilot data suggest improvements in joint engagement and regulation during play. Case series data show individual heterogeneity of intervention response. Remote intervention delivery may be associated with greater participant retention. CONCLUSIONS AND IMPLICATIONS: JASPER may be a viable treatment option to improve joint engagement and emotion regulation in young children with DS. Parents appear receptive to learning and implementing JASPER strategies at home. Remote JASPER delivery may improve participation in research or treatment programs.

Alterations in aperiodic and periodic EEG activity in young children with Down syndrome.

Down syndrome is the most common cause of intellectual disability, yet little is known about the neurobiological pathways leading to cognitive impairments. Electroencephalographic (EEG) measures are commonly used to study neurodevelopmental disorders, but few studies have focused on young children with DS. Here we assess resting state EEG data collected from toddlers/preschoolers with DS (n=29, age 13-48 months old) and compare their aperiodic and periodic EEG features with both age-matched (n=29) and cognitive-matched (n=58) comparison groups. DS participants exhibited significantly reduced aperiodic slope, increased periodic theta power, and decreased alpha peak amplitude. A majority of DS participants displayed a prominent peak in the theta range, whereas a theta peak was not present in age-matched participants. Overall, similar findings were also observed when comparing DS and cognitive-matched groups, suggesting that EEG differences are not explained by delayed cognitive ability.

Validation of factor structure of the neurodevelopmental parent report for outcome monitoring in down syndrome: confirmatory factor analysis.

Introduction: The Neurodevelopmental Parent Report for Outcome Monitoring (ND-PROM), initially developed to monitor developmental and behavioral functions in children with autism spectrum disorder (ASD), assesses symptoms across a wide range of domains relevant in Down syndrome (DS). Methods: Psychometric properties of ND-PROM were assessed in 385 individuals with DS and 52 with a combined diagnosis of DS and ASD (DS+ASD), whose caregivers completed the ND-PROM questionnaire for a clinical visit in a specialized Down syndrome program at a tertiary pediatric hospital. Confirmatory factor analysis was conducted to evaluate the internal structure validity of the ND-PROM. Measurement invariance was assessed, with a comparison group of 246 individuals with ASD, and latent mean differences between the DS and ASD-only groups, as well as the combined DS+ASD groups, were assessed. Results: Findings support the existence of the 12 clinically-derived factors in the DS population: Expressive Language, Receptive Language, Adaptive skills/Toileting, Social Emotional Understanding, Social Interaction, Independent Play, Sensory Processes, Challenging Behaviors, Impulse/ADHD, and Mental Health. Differences in response patterns of development and behaviors were observed between those with DS and those with ASD, including those with DS having higher abilities in nonverbal communication, social emotional understanding, and social interaction, and fewer restricted and repetitive behaviors and interests, impulsivity or ADHD symptoms, and mental health concerns compared to those with ASD. Individuals in the DS+ASD group had more difficulties with expressive and receptive language, nonverbal and social communication, social interaction, independent play, and adaptive skills than either the DS-only group or the ASD-only groups. Discussion: The ND-PROM has a desirable factor structure and is a valid and clinically useful tool that captures a range of distinct and independent areas of developmental and behavioral functioning in DS, for individuals with and without an ASD diagnosis.

Cross-Sectional Analysis of Caregiver-Reported Expressive Language Profiles and Associated Covariates in Individuals with Down Syndrome.

OBJECTIVE: To describe the distribution of expressive language abilities of individuals with Down syndrome (DS) in a clinical sample and characterize demographic, environmental, and medical factors associated with varying expressive language profiles. METHODS: Cross-sectional analysis was completed on a sample of 345 individuals with DS between the ages of 4 and 22 years who were enrolled into a longitudinal clinical database between March 2018 and August 2021. Expressive language-related items on a standardized caregiver-reported questionnaire assessing domains of functioning in neurodevelopmental disorders were used to conduct latent variable modeling and determine caregiver-reported expressive language (CREL) classes across the sample. Linear regression was used to explore associations between CREL classes and predictor variables. RESULTS: Latent variable modeling revealed 3 distinct classes of CREL abilities representing higher, middle, and lower CREL. Individuals in the lower CREL class were more likely to be female, to use sign language or visual communication systems, have reduced pronunciation, attend private or residential school, and to be in a substantially separate classroom. Membership was not predicted by complex medical histories or co-occurring neurodevelopmental diagnoses. CONCLUSION: Caregiver-reported expressive language abilities in a cohort of individuals with DS were variable, with most of the individuals belonging to higher or middle CREL classes, relative to one another. Additional studies are indicated to understand factors that predict higher expressive language ability and explore how to direct services to individuals who are at risk of more profound language delays.

Co-occurring conditions in Down syndrome: Findings from a clinical database.

Individuals with Down syndrome (DS) experience a range of medical and neurodevelopmental conditions, necessitating systematic study of their occurrence and impact on neurodevelopmental outcomes. We describe the prevalence and relationships of medical, neurodevelopmental (ND), and mental health (MH) conditions in children with DS. We created a prospective clinical database of individuals with DS, integrated into the workflow of a specialty Down Syndrome Program at a specialty pediatric referral hospital. Conditions were collected through caregiver- and clinician report at clinical visits (N = 599). We calculated frequencies of medical, ND, and MH conditions and then assessed the relationship between medical, ND, and MH conditions using frequencies and comparative statistics. The most frequent co-occurring conditions were vision (72.5%), ear/hearing (71.0%), gastrointestinal (61.3%), respiratory (45.6%), and feeding (33.6%) problems, with variation in frequency by age. ND and MH conditions were reported in one quarter, most commonly autism spectrum disorder and attention-deficit/hyperactivity disorder. Those with ND and MH conditions had greater frequency of medical conditions, with highest rates of vision, ear/hearing, and gastrointestinal issues, and CHD. Systematically collected clinical data in a large cohort of children with DS reveals high prevalence of several co-occurring medical, ND, and MH conditions. Clinical care requires an understanding of the complex relationship between medical conditions and neurodevelopment.

Clinically derived 12-factor structure and confirmatory factor analysis of the neurodevelopmental parent report for outcome monitoring.

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by social communication and social interaction impairments accompanied by restrictive and repetitive behaviors or interests. Co-occurring conditions may greatly impact overall functioning and intervention needs, and contribute to individual variability and etiologic subtypes. Clinical care of individuals with ASD requires gathering a breadth of information across multiple domains. The neurodevelopmental parent report for outcome monitoring (ND-PROM) was developed to assess symptoms across core features of ASD as well as frequent concerns and comorbidities. The current study expands upon the initially reported psychometric properties of the ND-PROM and evaluates a proposed a clinically derived 12-factor structure of the ND-PROM. Methods and procedures: The ND-PROM was completed for 246 children with ASD ands tested using confirmatory factor analysis (CFA) and measurement invariance based on sex. Outcomes and results: A 12-factor correlated structure was found (expressive language, receptive language, nonverbal communication, social emotional understanding, social interaction, independent play, adaptive/toileting skills, restrictive and repetitive behaviors and interests, sensory processes, challenging behaviors, impulse/ADHD, and mental health), which did not vary by sex. Conclusions and implications: The ND-PROM captures a range of distinct aspects of developmental and behavioral functioning in ASD that can be used to track independent functioning across domains.

Co-occurring conditions in children with Down syndrome and autism: a retrospective study.

BACKGROUND: Down syndrome (DS) is one of the most common genetic causes of intellectual disability, and it is associated with an increased incidence of numerous co-occurring conditions. Autism spectrum disorder (ASD) is common in persons with DS, with rates reported as high as 39%. However, little is known regarding co-occurring conditions in children with both DS and ASD. METHODS: A single-center retrospective review of prospective longitudinally collected clinical data was performed. Any patient with a confirmed diagnosis of DS evaluated at a large, specialized Down Syndrome Program in a tertiary pediatric medical center between March 2018 and March 2022 was included. A standardized survey which included demographic and clinical questions was administered during each clinical evaluation. RESULTS: In total, 562 individuals with DS were included. The median age was 10 years (IQR: 6.18-13.92). Of this group, 72 (13%) had a co-occurring diagnosis of ASD (DS+ASD). Individuals with DS+ASD were more likely to be male (OR 2.23, CI 1.29-3.84) and had higher odds of a current or prior diagnosis of constipation (OR 2.19, CI 1.31-3.65), gastroesophageal reflux (OR 1.91, CI 1.14-3.21), behavioral feeding difficulties (OR 2.71, CI 1.02-7.19), infantile spasms (OR 6.03, CI 1.79-20.34) and scoliosis (OR 2.73, CI 1.16-6.40). There were lower odds of congenital heart disease in the DS+ASD group (OR 0.56, CI 0.34-0.93). There was no observed difference in prematurity or Neonatal Intensive Care Unit complications between groups. Individuals with DS+ASD had similar odds of having a history of congenital heart defect requiring surgery to those with DS only. Furthermore, there was no difference in rates of autoimmune thyroiditis or celiac disease. There was also no difference in rates of diagnosed co-occurring neurodevelopmental or mental health conditions in this cohort, including anxiety disorders and attention-deficit/hyperactivity disorder. CONCLUSIONS: This study identifies a variety of medical conditions which are more frequent in children with DS+ASD than DS alone, providing important information for the clinical management of these patients. Future research should investigate the role of some of these medical conditions in the development of ASD phenotypes, and whether there may be distinct genetic and metabolic contributions towards these conditions.

Quality of Life and Family Impact in Down Syndrome, Autism Spectrum Disorder, and Co-occurring Down Syndrome and Autism Spectrum Disorder.

OBJECTIVE: Families of children with neurodevelopmental disorders have developmental, behavioral, and social-emotional needs that affect quality of life (QoL). This study assesses the validity and utility of a caregiver QoL measure; characterizes QoL in families with children with Down syndrome (DS), autism spectrum disorder (ASD), and a dual diagnosis of DS and ASD (DS + ASD); and compares and explores differences in QoL based on diagnosis. METHODS: Caregivers of children and adolescents with ASD (n = 610) and DS (n = 177) completed the Pediatric Quality of Life Inventory Family Impact Module 2.0, yielding overall, parent functioning, family functioning, and subscale scores, and a Parent Global Impression (PGI) rating. An ASD cohort (n = 177) was sex matched to the DS cohort (n = 177) to mitigate potential sex bias. Additional analyses compared these groups with children and adolescents with DS + ASD (n = 37). RESULTS: Analyses showed that the Pediatric Quality of Life Inventory was valid and reliable in DS, ASD, and DS + ASD populations. No differences were reported in PGI ratings among groups. Caregivers in the DS group demonstrated higher QoL and family functioning compared with the ASD and DS + ASD groups. The DS group reported significantly better Emotional Functioning and Communication and less Worry than the ASD group. Compared with the ASD group, caregivers of the DS + ASD group indicated more concerns with Physical Functioning. Notably, the DS + ASD group had significantly lower levels of QoL than the DS group in nearly all caregiver functioning domains. CONCLUSION: This study highlights differences in QoL within and between neurodevelopmental disorder groups, which may help identify families requiring additional support, advocacy, and community engagement.

Cardiometabolic profiles in children and adults with overweight and obesity and down syndrome.

Individuals with Down syndrome (DS) are at increased risk for being overweight/obese, but the associated cardiometabolic risk (CR) is not clear. Cross-sectional anthropometric and clinical laboratory data from a multi-site, international cohort of individuals with DS were analyzed to determine cardiometabolic risk by reporting observed distributions of cardiometabolic biomarkers in overweight/obese individuals with DS throughout the lifespan. Descriptive statistics and regression analyses by age categories determined the distributive percentiles for cardiometabolic biomarkers and tested for adiposity as a predictor of CR. Across seven DS clinics, data were collected on 240 patients between the ages of 3 and 63 years, with one quarter overweight and three quarters obese among children and nearly all adults being obese. In children and adults, most cardiometabolic biomarker profiles showed distributive values within normal ranges. Blood lipids were positively associated with body mass index (BMI) in children (high density lipid-cholesterol, p = 0.01; low density lipid-cholesterol, p = 0.02). Levels of hs-CRP were elevated in both children and adults, with BMI positively associated with hs-CRP in adults with DS (p = 0.04). Liver enzyme values were positively associated with BMI in children and adults. The data suggest that in contrast to the general population, in individuals with Down syndrome, being overweight and obese does not appear to confer a significantly increased risk for cardiometabolic disease by biomarker profile. Individuals with DS who are overweight/obese appear to have unique cardiometabolic profiles unrelated to adiposity, notable for increased hs-CRP and normal HA1c levels.

Development and implementation of a longitudinal clinical database for down syndrome in a large pediatric specialty clinic: Methodology and feasibility.

Down syndrome (DS) is a complex condition associated with multiple medical, developmental, and behavioral concerns. A prospective, longitudinal clinical database was integrated into a specialty Down Syndrome Program, with the goals of better understanding the incidence, course, and impact of co-occurring medical, neurodevelopmental, and mental health conditions in DS. We describe the process of developing the database, including a systematic approach to data collection and database infrastructure, and report on feasibility, challenges, and solutions of initial implementation. Between March 2018 and November 2021, data from 842 patients (ages 4.8 months to 26 years) was collected. Challenges included caregiver form completion as well as time and personnel required for successful implementation. With full integration into clinical visit flow, the database proved to be feasible. The database enables identification of patterns of development and health throughout the lifespan and it facilitates future data sharing and collaborative research to advance care.

Unexplained regression in Down syndrome: Management of 51 patients in an international patient database.

Research to guide clinicians in the management of the devastating regression which can affect adolescents and young adults with Down syndrome is limited. A multi-site, international, longitudinal cohort of individuals with a clinical diagnosis of Unexplained Regression in Down syndrome (URDS) was collated through seven Down syndrome clinics. Tiered medical evaluation, a 28-item core symptom list, and interim management are described naturalistically. Improvement-defined by the percentage of baseline function on a Parent-reported Functional Score, overall improvement in symptoms on a Clinician-administered Functional Assessment, or report of management type being associated with improvement-was analyzed. Improvement rates using ECT, IVIG, and others were compared. Across seven clinics, 51 patients with URDS had regression at age 17.6 years, on average, and showed an average 14.1 out of 28 symptoms. Longitudinal improvement in function was achieved in many patients and the medical management, types of treatment, and their impact on function are described. Management with intravenous immunoglobulin (IVIG) was significantly associated with higher rate of improvement in symptoms at the next visit (p = 0.001). Our longitudinal data demonstrates that URDS is treatable, with various forms of clinical management and has a variable course. The data suggests that IVIG may be an effective treatment in some individuals. Our description of the management approaches used in this cohort lays the groundwork for future research, such as development of standardized objective outcome measure and creation of a clinical practice guideline for URDS.

Is Developmental Regression in Down Syndrome Linked to Life Stressors?

OBJECTIVE: Unexplained regression in Down syndrome (URDS) involves a loss of acquired skills resulting in functional deterioration. Despite extensive workup and treatment, few individuals regain baseline function. This study aimed to understand the role of psychosocial stressors in URDS. METHODS: We describe psychosocial stressors in 14 cases of URDS. Specifically, we examined psychosocial stressors in the context of presentation and clinical symptoms. We also examined co-occurring neurodevelopmental disorders and medical and mental health conditions. RESULTS: All individuals experienced psychosocial stressors within one year of diagnosis of URDS. The most common psychosocial stressors were moving to a new home or school. CONCLUSION: Psychosocial stressors are commonly reported preceding URDS. Knowledge about psychosocial stressors' impact may lead to preventive interventions, improved monitoring, and earlier diagnosis. Future research should focus on understanding psychosocial stressors to help identify individuals at risk for URDS and contribute to treatment.

Autism Spectrum Disorder Parent Report for Outcome Monitoring: A Preliminary Report of Development and Clinical Utility.

OBJECTIVE: Children with autism spectrum disorder (ASD) face challenges across many functional domains. A tool that gathers relevant clinical information before visits, emphasizing symptoms that are likely to change over development and inform clinical interventions, could improve health care quality, allowing for more patient-centered and efficient care. This study evaluated the clinical utility and preliminary psychometrics of the ASD Parent Report for Outcome Monitoring (ASD-PROM), a web-based measure assessing competence in core features of ASD, along with the breadth of concerns and comorbidities that frequently co-occur with ASD. METHODS: An interdisciplinary team drafted the ASD-PROM and made iterative revisions based on parent feedback. Parents of 62 children completed the ASD-PROM before their autism-specialty clinical visit, 53 completed the ASD-PROM twice, and 48 completed the Vineland Adaptive Behavior Scales, Second Edition (Vineland-II) concurrently. Parents (n = 25) and clinicians (n = 13) completed postvisit surveys to assess utility (phase 1). The ASD-PROM was then released for general clinical use (phase 2). RESULTS: On a Likert scale (1 = very poorly, 10 = very well), parents found that ASD-PROM items described their child's abilities well (median = 8.0; interquartile range [IQR]: 7.0-9.5) and had a positive effect on care (median = 8.0; IQR: 7.0-10.0). Clinicians found the ASD-PROM effective in assessing parent-reported patient abilities (median = 9.0, IQR: 7.0-9.0) and felt the ASD-PROM helped make their care more patient-centered and efficient (both median = 8.0, IQR: 6.0-9.0). Two-week test-retest reliability was acceptable (0.95). ASD-PROM scores correlated positively with scores from similar domains on the Vineland-II (Pearson r 0.30-0.50, medium to large effects). CONCLUSION: The ASD-PROM is a freely available tool to gather information on developmental and behavioral functioning in children with ASD before autism-specialty clinical visits. Clinical utility and preliminary psychometrics are promising, although limitations (including a low response rate during clinical use and a need for additional in-depth assessments and potential resulting modifications to the tool) remain to be addressed. Ultimately, the ASD-PROM may help promote patient-centered and efficient care for children across a wide range of ages and developmental levels.

Investigating Potential Biomarkers in Autism Spectrum Disorder.

BACKGROUND: Early identification and treatment of individuals with autism spectrum disorder (ASD) improves outcomes, but specific evidence needed to individualize treatment recommendations is lacking. Biomarkers that could be routinely measured within the clinical setting could potentially transform clinical care for patients with ASD. This demonstration project employed collection of biomarker data during regular autism specialty clinical visits and explored the relationship of biomarkers with clinical ASD symptoms. METHODS: Eighty-three children with ASD, aged 5-10 years, completed a multi-site feasibility study integrating the collection of biochemical (blood serotonin, urine melatonin sulfate excretion) and clinical (head circumference, dysmorphology exam, digit ratio, cognitive and behavioral function) biomarkers during routine ASD clinic visits. Parents completed a demographic survey and the Aberrant Behavior Checklist-Community. Cognitive function was determined by record review. Data analysis utilized Wilcoxon two-sample tests and Spearman correlations. RESULTS: Participants were 82% male, 63% White, 19% Hispanic, with a broad range of functioning. Group means indicated hyperserotonemia. In a single regression analysis adjusting for race and median household income, higher income was associated with higher levels of blood serotonin and urine melatonin sulfate excretion levels (p = 0.004 and p = 0.04, respectively). Melatonin correlated negatively with age (p = 0.048) and reported neurologic problems (p = 0.02). Dysmorphic status correlated with higher reported stereotyped behavior (p = 0.02) and inappropriate speech (p = 0.04). CONCLUSION: This demonstration project employed collection of multiple biomarkers, allowed for examination of associations between biochemical and clinical measures, and identified several findings that suggest direction for future studies. This clinical research model has promise for integrative biomarker research in individuals with complex, heterogeneous neurodevelopmental disorders such as ASD.

Feasibility of Conducting Autism Biomarker Research in the Clinical Setting.

OBJECTIVE: Recruitment and completion of research activities during regular clinical care has the potential to increase research participation in complex neurodevelopmental disorders. We evaluated the feasibility, and effect on clinical care, of conducting biomarker research within a subspecialty clinical visit for autism spectrum disorder (ASD). METHODS: Children, aged 5 to 10 years, were recruited by providers in ASD clinics at 5 institutions. Biomarkers collected were growth measurements, head circumference, neurologic and dysmorphology examinations, digit ratio (2D:4D) measurement, and platelet serotonin and urinary melatonin sulfate excretion levels. Parents completed the Aberrant Behavior Checklist-Community and a medical/demographic questionnaire. Cognitive level was abstracted from the medical record. Parents and clinicians completed surveys on the effect of the study on the clinical visit. RESULTS: Eighty-three children and their caregivers participated. Factors limiting participation included difficulty reaching families by phone and parent concern about the study blood draw requirement. All children completed at least 4 of 7 planned research activities. Demographic factors, educational placement, and child behavior were not associated with completion of study activities. Lower nonverbal cognitive function was weakly associated with fewer activities completed. Forty-four percent of clinicians reported an effect of the research study on the clinical visit. However, neither parent-reported nor clinician-reported effect was associated with the degree of study activity completion. CONCLUSION: Recruiting study participants in the context of scheduled ASD clinical visits required significant effort. However, once recruited, participants completed most study activities, regardless of behavioral symptom severity. Research activities did not adversely affect the clinical visit.

Review of Salient Investigational Drugs for the Treatment of Fragile X Syndrome.

OBJECTIVES: Fragile X syndrome (FXS) is the most common inherited cause of intellectual disability, in addition to being the commonest diagnosable cause of autism. The identification of the biochemical mechanism underlying this disorder has provided amenable targets for therapy. This review aims to provide an overview of investigational drug therapies for FXS. METHODS: The authors carried out a search of clinical and preclinical trials for FXS in PubMed and on the U.S. National Institutes of Health index of clinical trials ( www.clinicaltrials.gov ). We limited our review to Phase II trials or more preliminary and reviewed the associated publications for these studies, complemented by a review of the literature on PubMed. RESULTS: The review of the preclinical, Phase I, and Phase II trials of agents with therapeutic potential in FXS revolves around an understanding of the putative pathways in the pathogenesis of FXS. While there is significant overlap between some of these pathways, the agents can be categorized as modulators of the metabotropic glutamate receptor system, GABAergic agents, and miscellaneous modulators affecting other pathways. CONCLUSION: As trials involving agents targeting different aspects of the molecular biology proceed, common themes have emerged. With the great hope came great disappointment as the initial trials failed to demonstrate sufficient significance. In particular, the differences in outcome between the animal models and humans have highlighted the unique challenges of carrying out trials in these cognitively and behaviorally challenged individuals, as well as a dearth of clinically relevant outcome measures for use in medication trials. However, in reviewing and reframing the studies of the last decade, many important lessons have been learned, which will ultimately have a greater impact on therapeutic research in the field of developmental delay as a whole.