Young Children's Measure Research Articles

The Effects of Sedation on Auditory Brainstem Response in Pediatric Population: A Systematic Review

Background and Aim: Auditory Brainstem Response (ABR) is crucial for evaluating auditory pathway function in pediatric patients. However, obtaining reliable ABR measurements in young children can be challenging due to their inability to stay still and quiet during the test. Sedation is frequently used to facilitate ABR testing in this population, but the most practically effective sedation method and its impact are still uncertain. This systematic review aimed to thoroughly investigate the success rates (completion of ABR in both ears) associated with different sedation techniques. Recent Findings: In recent review (2000-2022), Ten studies, identified through a comprehensive search of electronic databases, were included in the analysis. The studies reported significant variation in success rates for ABR testing with sedation, ranging from 70% to 100%. This suggests that the effectiveness of sedation may not be uniform across all situations. The included studies employed a wide variety of sedation techniques, highlighting the lack of a standardized approach in this area. Conclusion: These findings highlight the heterogeneity in sedation practices and success rates for pediatric ABR testing. This emphasizes the importance of tailoring the sedation approach to the specific needs of each child while carefully considering the potential risks associated with each sedation method. Further research is warranted to establish standardized protocols for sedation in pediatric ABR , ensuring optimal test efficacy while prioritizing patient safety. Research Square registration.Keywords: Auditory brainstem response; sedation; chloral hydrate; children; dexmedetomidine; intranasal drug administration

The measurement of young children’s nocturnal sleep health and the development of the Perception of Infant and Toddler Sleep Scale (PoITSS) in Aotearoa New Zealand whānau (families)

ObjectivesTo modify an existing questionnaire Brief Infant Sleep Questionnaire – Revised (BISQ-R) to ensure that it is suitable to measure nocturnal sleep health in a diverse sample of young children from Aotearoa New Zealand whānau (families), and to develop a “Perception of Infant and Toddler Sleep Scale” (PoITSS) to use as a primary outcome measurement in an upcoming trial. MethodsItems from the BISQ-R were adapted for use among ethnically diverse whānau, and tested online with caregivers of 0-2 year old children. A PoITSS score was generated by scaling the responses from three of the questionnaire items to create a value between 0 (very poor) and 10 (very good). Caregivers provided qualitative feedback about the ease of interpreting and answering questionnaire items. ResultsCaregivers of 957 children (35% Māori, 12% Pacific) completed the questionnaire. Few differences in children’s nocturnal sleep were observed by demographic characteristics. The mean PoITSS score was 6.9 (SD 2.3) and was slightly higher among Māori children (mean difference 0.4, 95% CI 0.1, 0.7). Test-retest indicated good reliability (ICC=0.81). While the majority (86%) of caregivers did not find it difficult to answer any of the items which formed the PoITSS, qualitative feedback indicated that simple modifications to some items would help ensure that they would be well understood by most caregivers. ConclusionsItems from the BISQ-R were successfully adapted, and the PoITSS scale was shown to be appropriate, for use in ethnically diverse Aotearoa New Zealand whānau with young children.

Comparing surface electroenterography measurements between patients suffering from Hirschsprung’s disease and controls: a feasibility study

Current diagnostics in Hirschsprung’s disease are often challenging and invasive. This study aims to investigate whether surface electroenterography can non-invasively discern healthy subjects from subjects suffering from Hirschsprung’s disease. Nine healthy subjects (seven children, two adults) and eleven subjects suffering from surgically untreated Hirschsprung’s disease (nine children, two adults) underwent an electroenterography procedure. This procedure consisted of ultrasound-guided placement of surface electrodes on the abdomen covering all parts of the colon, fasting and two 20-min electroenterography measurements separated by a meal. The dominant frequency, magnitude and relative increase (pre- to postprandial) of colonic activity were compared between both groups. The results showed that in the pediatric group, no significant differences in dominant frequency, colonic activity and relative power increase were observed between controls and patients. The adult patients showed decreased colonic motility and relative power increase in the electrodes closest to the distal colon, both when compared to the same electrodes in controls and to the more proximal electrodes of themselves. To conclude, electroenterography measurements in young children is challenging, but the results in adults demonstrate that these measurements can possibly distinguish between controls and Hirschsprung’s patients. Therefore, optimization of electroenterography measurements in young children is necessary.

Ambulatory Nursing Care for Young Children Suffering from Febrile Convulsions

Background: Specialist ambulatory care Nursing is a complicated, diverse profession that includes solitary and group practice. Young children who experience febrile seizures, often known as fits or convulsions, are affected by fever. Aim: It aimed to assess ambulatory nursing care for young children suffering from febrile convulsions. Design: Descriptive research design is used. Sample: A convenient sample for all ambulatory nurses they were 100 nurses. Setting: Study conducted at all outpatient clinics at Central Children's Hospital, Al-zahrawi ( Ibn Al-Baladi.) Teaching hospital and Welfare children teaching hospital Two tools: 1st Structural interviewing questionnaire composed of two parts (demographic characteristics, ambulatory nurse knowledge about febrile convulsions), second tool: observation checklist of ambulatory nurse practice. Results: Regarding ambulatory nurses' knowledge about Febrile Convulsions, 65% of nurses have satisfactory knowledge, 35% of them have unsatisfactory knowledge regarding febrile convulsions, Also, 70% of nurses done practice, and 25.0% of them not done practice and 5% of them do not know regarding measurement young children body temperature under axillary, While, 65% of nurses done practice, and 20.0% of them not done practice and 15% of them do not know regarding the right way to make tap compresses and 70.0% of nurses done practice, and 20.0% of them not done practice and 10% of them do not know regarding the right way to give oxygen therapy. Conclusion: there was a positive relation between nurses' total knowledge and total practice regarding the right way to measure body temperature, the measurement of young children's temperature under axillary, and the right way to give oxygen therapy with statistical significance difference between nurses' knowledge and practice regarding febrile convulsions (p< 0.001). Recommendations: Continuous health education and training programs for the nurses about febrile convulsions.

Clinically meaningful change threshold in health‐related quality of life among patients aged 6 months to 5 years with atopic dermatitis and their caregiver(s)/family

AbstractBackgroundAtopic dermatitis (AD) significantly impacts health‐related quality of life (HRQoL) in children and their caregiver(s)/family. Measures to assess HRQoL include the Children's Dermatology Life Quality Index (CDLQI), Infants' Dermatitis Quality of Life Index (IDQoL) and Dermatitis Family Impact (DFI) questionnaire. Currently, there are no established clinically meaningful within‐person change thresholds for these measures in young children (6 months to 5 years) and their caregiver(s)/family.ObjectivesTo determine the clinically meaningful within‐person change thresholds for CDLQI (4–5 years), IDQoL (<4 years) and DFI scores in children aged 6 months to 5 years with moderate‐to‐severe AD and their caregiver(s)/family.MethodsData from the 16‐week, randomised, double‐blind, placebo‐controlled, phase 3 LIBERTY AD PRESCHOOL part B study in children aged 6 months to 5 years were used. The anchor‐based method was used to assess meaningful change thresholds for the three instruments, using the Caregiver Global Impression of Disease (CGID; range: ‘no symptoms’ to ‘very severe’) as the primary anchor, and Caregiver Global Impression of Change (CGIC; range: ‘much better’ to ‘much worse’) as a supportive anchor.ResultsThe mean CDLQI change scores were −6.3 and −9.5 based on CGID 1‐point improvement and CGIC improvement of ‘a little better’, respectively. The mean IDQoL change scores were −5.6 and −3.4 based on the CGID and CGIC anchors. The mean DFI change scores were −7.0 and −6.7 based on the CGID and CGIC anchors.ConclusionsBased on primary anchor findings, improvements of ≥6 points on the CDLQI total score for children aged 4–5 years and on the IDQoL total score for children aged <4 years were recommended as the clinically meaningful within‐person change thresholds in children with moderate‐to‐severe AD. A 7‐point improvement on the DFI total score may be considered as the meaningful threshold for the caregiver(s)/family of children aged 6 months to 5 years with moderate‐to‐severe AD.

The association between parent-child quality time and children's flourishing level

PurposeFew studies have examined the association between parental quality time and flourishing measures in young children. This study explored the association between parental quality time and children's flourishing in a national sample of USA children 1–5 years of age. Design and methodsA cross sectional study using data from the 2019–2020 National Survey of Children's Health (N = 17,855). Flourishing was measured with a composite score (values 0–4) derived from 4 questions on attachment with parent, resilience, learning, and contentment with life. Having all 4 items was optimal. Parent-child quality time per week was measured with 3 items: singing or storytelling, reading to child, and family meal with child; using a 4-point scale: 0 days, 1–3 days, 4–6 days, and every day/week. Multivariable logistic regression models were conducted to assess the odds of lower flourishing in SAS 9.4. ResultsAfter controlling for confounding, only the lack of singing and storytelling were negatively associated with greater odds of lower levels of flourishing (0–2 items OR = 5.06, 95% CI 2.11–12.14; 3 items OR = 2.92, 95% CI 1.73–4.93). ConclusionsInsufficient parent-child quality time is associated with lower flourishing levels. Fostering parental opportunities to engage in weekly quality time with their children should be a priority of child health programs seeking to improve child flourishing. Practice implicationsNurses should provide guidance to parents on ways to nurture quality family time and promote children's psychosocial, environmental, and physical well-being. Nurses can advocate for programmatic and policy changes to ensure familial work/life balance and licensing/accreditation of all child centers.

In childhood, a different electrode placement improves the recording of pattern reversal visual evoked potentials.

In childhood, a different electrode placement improves the recording of pattern reversal visual evoked potentials.

Caregivers’ perspectives on health-related quality of life in young children with TB and respiratory illnesses

There is a lack of holistic health-related quality of life (HRQoL) measures for young children with respiratory disease, especially in low- and middle-income countries (LMICs). We aimed to understand caregivers' perceptions of the relevance of common HRQoL domains for children with respiratory diseases, including TB. This study was nested in a prospective observational cohort of children presenting with respiratory symptoms presumptive of pulmonary TB. We conducted 10 semi-structured interviews to explore caregivers' perceptions of the five commonly measured HRQoL domains: physical health, social support, emotional and psychological wellbeing, and schooling. We used case descriptive analysis and thematic coding. Caregivers considered all five domains to be relevant. The socio-economic context framed their responses, with QoL requiring sufficient basic resources for children. HRQoL experiences varied according to the severity of the child's symptoms, but not between TB and non-TB illnesses. Manifestations in the psychological domain were difficult to distinguish from the emotional domain. Social support included broad support for family members, indirectly benefiting the children. Caregivers were concerned about their children's early developmental milestones and future schooling. This exploratory study shows that HRQoL domains are relevant but require adaptation to be applicable for young children affected by respiratory illnesses living in LMICs.

Psychometric Properties of Attention Measures in Young Children with Neurofibromatosis Type 1: Preliminary Findings.

Children with neurofibromatosis type 1 (NF1) often demonstrate difficulties with attention and executive functioning that can be evident starting at a young age. There has been little research about which measures of attention are most suitable for use with young children with NF1. This pilot study explored several computerized measures of attention, a digits forward task, and parent report measures of attention to compare their reliability, validity, and the degree to which they capture attention difficulty in this population. Participants with NF1 ages 4 to 6 years were seen for one (n=2) or two (n=18) time points. Statistical analyses for evaluating evidence for test-retest reliability, convergent and discriminant validity, practice effects, and identification of difficulties were conducted. Each measure demonstrated relative strengths and weaknesses, and there may not be a “one size fits all” measure for use with young children with NF1. However, the Behavior Rating Inventory of Executive Function Preschool/Second Edition, Conners Early Childhood Inattention/Hyperactivity Scale, and the Conners Kiddie Continuous Performance Test Second Edition generally had the highest reliability and most evidence of validity. More specific recommendations are provided for the appropriate measure to use in clinical and research batteries.

Reference Ranges for Bone Mineral Content and Density by Dual Energy X-Ray Absorptiometry for Young Children.

Assessment of bone health in young children has been hampered by limited reference values for bone mineral content (BMC) and areal bone mineral density (aBMD) by dual energy X-ray absorptiometry (DXA). To identify age, sex, and population ancestry effects on BMC and aBMD and develop smoothed reference ranges for BMC and aBMD in young children. To quantify precision of bone measurements and influence of height-for-age Z-scores on bone Z-scores. We recruited 484 healthy children ages 1 to 2 years or 4.5 to 5 years at 2 clinical centers, who were seen once or up to 7 times over a 3-year period. Lumbar spine, distal forearm, and whole-body subtotal (ages ≥ 3 years) BMC and aBMD were measured by DXA. These data were combined with data from the Bone Mineral Density in Childhood Study from children ages 5 to 8.9 years to create the smoothed reference curves. For 1- to 5-year-olds, BMC and aBMD at all skeletal sites increased with age. Age trends differed by sex for BMC and aBMD of the spine, distal one-third radius, ultradistal radius, and by ancestry (Black vs non-Black) for all measures. BMC and aBMD precision (% coefficient of variation) ranged from 1.0% to 4.4%. Height Z-scores were positively associated with bone Z-scores and accounted for 4% to 45% of the variance. We demonstrate the feasibility of bone density measurements in young children and provide robust reference ranges and stature adjustments for calculation of bone Z-scores at multiple skeletal sites to enable bone health assessments.

Reliability of a novel technique to assess palmar contracture in young children with unilateral hand injuries

BackgroundPalmar contracture in young children can have significant developmental consequences. Despite this, objective techniques to measure palmar range of movement and quantify contracture in young children are limited. PurposeThe purpose of this study was to determine the reliability of hand span and hand length measures in young children and to establish whether there is any association with age, sex and presence of a palmar burn injury in the reliability of these measures. The study also sought to determine the normative difference and establish a cut off value for the between-hand difference to identify loss of movement in 1 hand. Study designCross sectional MethodsForty-four children aged 0 to <5 years were recruited. Twenty-two children had a unilateral palmar burn injury and 22 did not have a palmar burn injury. Each child's hand span and hand length were measured 3 times. This was performed twice by the first assessor and once by the second assessor. Intraclass correlation coefficients were calculated to determine the intra-rater and inter-rater reliability. The largest of the 3 values for both hand span and hand length from the first assessor's first assessment were used to determine the normative between-hand difference. Outliers were removed prior to determining the normative difference. Children were considered outliers if their between-hand difference in hand span and/or hand length was in the top 5% of values. ResultsExcellent reliability was established for hand span and hand length measures for the whole group (intra-rater ICC2,1 ≥0.95, inter-rater ICC2,1 ≥0.94). The mean normative between-hand difference for both measures was 2 mm. The cut-off for the normative difference in hand span was <9 mm and hand length was <6 mm. ConclusionThis measurement technique has excellent reliability and could be a useful method to quantify palmar range of movement and identify contracture in young children with unilateral hand injuries.

Reliability, minimal detectable change and measurement errors in knee extension muscle strength measurement using a hand-held dynamometer in young children.

[Purpose] Few studies have assessed the reliability of muscle strength measurement using a hand-held dynamometer, specifically in Japanese young children. This study aims to investigate the reliability, minimal detectable change and measurement error in knee extension muscle strength measurements in young children using a hand-held dynamometer. [Participants and Methods] The study participants comprised 36 kindergarten-enrolled children of 3–6 years age. An experienced physiotherapist measured their isometric knee extension strength. Appropriate orientation and practices were performed prior to measurement. The same physiotherapist took the muscle measurements twice; and the maximum value was used as the muscle strength value. The measurements were repeated at intervals of approximately 30 min to verify reproducibility. [Results] The initial isometric knee extension strength was 10.6 ± 3.3 kgf and the Intra-class correlation coefficient (1,1) was 0.765. The standard error of measurement was 1.6 kgf and the minimal detectable change was 4.4 kgf. No significant systematic errors were observed. [Conclusion] Isometric knee extension strength measurement using a hand-held dynamometer in young children has good reliability with a low risk of systematic errors.

Maternal cannabis use is associated with suppression of immune gene networks in placenta and increased anxiety phenotypes in offspring

While cannabis is among the most used recreational drugs during pregnancy, the impact of maternal cannabis use (mCB) on fetal and child development remains unclear. Here, we assessed the effects of mCB on psychosocial and physiological measures in young children along with the potential relevance of the in utero environment reflected in the placental transcriptome. Children (∼3 to 6 y) were assessed for hair hormone levels, neurobehavioral traits on the Behavioral Assessment System for Children (BASC-2) survey, and heart rate variability (HRV) at rest and during auditory startle. For a subset of children with behavioral assessments, placental specimens collected at birth were processed for RNA sequencing. Hair hormone analysis revealed increased cortisol levels in mCB children. In addition, mCB was associated with greater anxiety, aggression, and hyperactivity. Children with mCB also showed a reduction in the high-frequency component of HRV at baseline, reflecting reduced vagal tone. In the placenta, there was reduced expression of many genes involved in immune system function including type I interferon, neutrophil, and cytokine-signaling pathways. Finally, several of these mCB-linked immune genes organized into coexpression networks that correlated with child anxiety and hyperactivity. Overall, our findings reveal a relationship between mCB and immune response gene networks in the placenta as a potential mediator of risk for anxiety-related problems in early childhood.

483: Statistical analysis for assessing reproducibility of gut microbiome compositional measurements in young children with cystic fibrosis

483: Statistical analysis for assessing reproducibility of gut microbiome compositional measurements in young children with cystic fibrosis

Inequalities in Exposure to Ambient Air Neurotoxicants and Disparities in Markers of Neurodevelopment in Children by Maternal Nativity Status.

Exposure levels to environmental pollutants vary significantly among different populations. These inequities in exposure to hazardous air pollutants (HAP) among different populations can contribute to disparities in neurodevelopmental outcomes. The aim of this study was to determine if exposure to HAP varies by maternal nativity status, a demographic marker often overlooked in the study of health disparities. We also assessed if those inequalities in exposure levels are associated with neurodevelopmental measures in young children. To do this, we obtained data from the Early Childhood Longitudinal Study-Birth cohort (ECLS-B), a nationally representative sample of children born in the U.S. in the year 2001 (n = 4750). Bayley’s Short Form-Research Edition (BSF-R) was used to measure cognitive development at 2 years of age. Using residential location at nine months of age, participants were assigned exposures to ten HAPs identified as potentially neurotoxic. Linear regression models were used to assess the joint effect of maternal nativity status and HAP exposure on neurodevelopment. Results showed inequities in exposure levels to ten different HAPs among the populations, as approximately 32% of children of foreign-born mothers were exposed to high levels of HAPs, compared to 21% of children born to U.S.-born mothers. Adjusting for socioeconomic factors, both isophorone exposure (a marker of industrial pollution) (−0.04, 95% CI, −0.12, 0.04) and maternal nativity status (−0.17, 95% CI, −0.27, −0.06) were independently associated with lower standardized BSF-R mental scores in children. Interaction between nativity status and isophorone was not statistically significant, but the change in mental scores associated with isophorone exposure was greater in children of foreign-born mothers compared to children of U.S.-born mothers (−0.12, vs. −0.03, p = 0.2). In conclusion, exposure to HAPs within the highest quartile was more commonly found among children of foreign-born mothers as compared to children of US-born mothers, indicating inequities in pollutant exposure by nativity status within urban populations. Exposures associated with nativity status may negatively contribute to children’s neurodevelopment.

The influence of body position on bioelectrical impedance spectroscopy measurements in young children

Bioelectrical impedance techniques are easy to use and portable tools for assessing body composition. While measurements vary according to standing vs supine position in adults, and fasting and bladder voiding have been proposed as additional important influences, these have not been assessed in young children. Therefore, the influence of position, fasting, and voiding on bioimpedance measurements was examined in children. Bioimpedance measurements (ImpediMed SFB7) were made in 50 children (3.38 years). Measurements were made when supine and twice when standing (immediately on standing and after four minutes). Impedance and body composition were compared between positions, and the effect of fasting and voiding was assessed. Impedance varied between positions, but body composition parameters other than fat mass (total body water, intra- and extra-cellular water, fat-free mass) differed by less than 5%. There were no differences according to time of last meal or void. Equations were developed to allow standing measurements of fat mass to be combined with supine measurements. In early childhood, it can be difficult to meet requirements for fasting, voiding, and lying supine prior to measurement. This study provides evidence to enable standing and supine bioimpedance measurements to be combined in cohorts of young children.

Examining Psychometrics of the Frost Multidimensional Perfectionism Scale in Children Ages 8-12 Years Using Child and Parent Report.

Perfectionism, especially the evaluative concerns domain, correlates positively with mental health distress. The Frost Multidimensional Perfectionism Scale (F-MPS) is one of the most widely used measures of perfectionism, but has not been validated in children or as a measure of parent-report of child perfectionism. The present study aimed to validate the reliability and concurrent, convergent, and factor analytic validity of the F-MPS as a measure for young children. The F-MPS was administered to a sample of 114 children ages 8-12, and their parent. Results suggest that the F-MPS is valid for parent, but not child, report of child perfectionism. The lack of support for the child report may be due to developmental limitations of children understanding and reporting of their own perfectionism traits. In contrast, parent-report using the brief version of the F-MPS appears to be an economical and valid measure of perfectionism in young children. Improved measures of perfectionism in youth would aid in early intervention to buffer the negative mental health effects of the maladaptive aspects of perfectionism.

Urinary phthalates and body mass index in preschool children: The MIREC Child Development Plus study.

Childhood exposure to phthalates, a class of chemicals with known reproductive and developmental effects, has been hypothesized to increase the risk of obesity, but this association is not well understood in preschool children. We examined the association between urinary concentrations of phthalate metabolites and concurrently measured body mass index (BMI) and skinfolds among children between the ages of two and five years. We collected anthropometric measures and biomonitoring data on approximately 200 children enrolled in the Maternal-Infant Research on Environmental Chemicals Child Development Plus study. We measured 22 phthalate metabolites in children's urine and used the 19 metabolites detected in at least 40% of samples. Our primary outcome was BMI z-scores calculated using the World Health Organization growth standards. Skinfold z-scores were secondary outcomes. We used multivariable linear regression to evaluate the association between tertiles of phthalate concentrations and each anthropometric measure. We also used weighted quantile sum regression to identify priority exposures of concern. Our analytic sample included 189 singleton-born children with complete anthropometric data. Children with concentrations of the parent compound di-n-butyl phthalate (∑DnBP) in the third tertile had 0.475 (95% CI: 0.068, 0.883) higher BMI z-scores than those in the lower tertile. ∑DnBP was identified as a priority exposure in the weighted quantile sum regression BMI model. In this population of Canadian preschool aged children, we identified DnBP as a potential chemical of concern in regard to childhood obesity. Future research with serial phthalate measurements and anthropometric measurements in young children will help confirm these findings.

Exploring the dimensionality of kindergarten written composition

Despite increasing pressure for children to learn to write at younger ages, there are many unanswered questions about composition skills in early elementary school. The goal of this research was to examine the dimensionality of composition skills in kindergarten children, thereby adding to current knowledge about the measurement of young children’s writing and its component skills. The writing of 282 kindergarten children were assessed using three different scoring methods. Confirmatory factor analyses were used to investigate the dimensionality of various methods of scoring. Results indicated that a qualitative scoring system and a productivity scoring system capture distinct dimensions of kindergartners’ compositions. A scoring system for curriculum-based measurement could not attain acceptable fit, which may suggest that CBM is ill-suited for capturing the important components of composition for kindergartners. This study indicated that the measurement and components of composition in kindergarten may be qualitatively different from the compositions of older children.

Surface- and voxel-based brain morphologic study in Rett and Rett-like syndrome with MECP2 mutation

Rett syndrome (RTT) is a rare congenital disorder which in most cases (95%) is caused by methyl-CpG binding protein 2 (MECP2) mutations. RTT is characterized by regression in global development, epilepsy, autistic features, acquired microcephaly, habitual hand clapping, loss of purposeful hand skills, and autonomic dysfunctions. Although the literature has demonstrated decreased volumes of the cerebrum, cerebellum, and the caudate nucleus in RTT patients, surface-based brain morphology including cortical thickness and cortical gyrification analyses are lacking in RTT. We present quantitative surface- and voxel-based morphological measurements in young children with RTT and Rett-like syndrome (RTT-l) with MECP2 mutations. The 8 structural T1-weighted MR images were obtained from 7 female patients with MECP2 mutations (3 classic RTT, 2 variant RTT, and 2 RTT-l) (mean age 5.2 [standard deviation 3.3] years old). Our analyses demonstrated decreased total volumes of the cerebellum in RTT/RTT-l compared to gender- and age-matched controls (t (22)=-2.93, p = .008, Cohen’s d = 1.27). In contrast, global cerebral cortical surface areas, global/regional cortical thicknesses, the degree of global gyrification, and global/regional gray and white matter volumes were not statistically significantly different between the two groups. Our findings, as well as literature findings, suggest that early brain abnormalities associated with RTT/RTT-l (with MECP2 mutations) can be detected as regionally decreased cerebellar volumes. Decreased cerebellar volume may be helpful for understanding the etiology of RTT/RTT-l.