Promoting toddlers' self-regulation and healthy eating habits among families living in poverty: A randomized controlled trial of Recipe 4 Success.

The Recipe 4 Success preventive intervention targeted multiple factors critical to the health and well-being of toddlers living in poverty. This randomized controlled trial, which was embedded within Early Head Start home visits for 12 weeks, included 242 racially and ethnically diverse families (51% girls; toddler mean age = 2.58 years; data collected 2016-2019). Compared to parents in usual practice home visits, parents in Recipe 4 Success displayed greater sensitive scaffolding of toddlers' learning and more responsive food parenting practices (Cohen's d = .21-.30). Toddlers in Recipe 4 Success exhibited greater self-regulation and had healthier eating habits (Cohen's d = |.16-.35|). Results highlight the value of Recipe 4 Success in promoting parent and toddler behavior change that could have life-long benefits.

Evolving approaches in paediatric thyroid cytopathology: A review.

The guidelines for the workup of thyroid nodules have been established in adult populations and secondarily applied to paediatric populations. In particular, The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) is commonly applied to both adult and paediatric thyroid nodules. However, as paediatric nodules have distinct molecular drivers and behavioural trajectories, there is renewed interest in diagnostic and management strategies that are paediatric specific. Here, we review key differences between paediatric and adult thyroid cancer and recent literature evaluating the use of TBSRTC in paediatric populations.

Evaluation and application of American College of Radiology Thyroid Imaging Reporting and Data System for improved malignancy detection in paediatric thyroid nodules.

OBJECTIVE: The American College of Radiology Thyroid Imaging Reporting and Data System (TI-RADS) is a widely used method for the management of adult thyroid nodules. However, its use in paediatric patients is controversial because adult fine needle aspiration biopsy (FNAB) recommendations may lead to delayed diagnoses of cancer in children. The objectives of this study were to evaluate the performance of TI-RADS in paediatric thyroid nodules and to tailor FNAB recommendations for children. METHODS: Consecutive surgically resected paediatric thyroid nodules from two tertiary care centres between 2003 and 2021 were reviewed. Ultrasounds were blindly scored by radiologists according to TI-RADS. Management recommendations based on TI-RADS were evaluated. Various modelling methodologies were used to determine the optimal cutoff for FNAB in children. RESULTS: Of the 96 patients, 79 (82%) were female and the median age at surgery was 16.1 years. Fifty (52%) nodules were malignant on surgical pathology. The area under the receiver operating characteristic curve of TI-RADS for predicting malignancy was 0.78. Adult TI-RADS recommendations would have resulted in 4% of cancerous nodules being lost to follow-up. Modifications to TI-RADS (FNAB of all TR3 nodules ≥1.5 cm, FNAB of TR4 and TR5 nodules ≥0.5 cm, surveillance of nodules ≥1 cm, consider surgery for nodules >4 cm) reduced this missed malignancy rate to 0%. CONCLUSIONS: TI-RADS can risk-stratify paediatric thyroid nodules. However, the system requires modifications to reduce the missed malignancy rate in paediatric thyroid nodules. Our data suggest that lower size thresholds for FNAB are warranted in children.

Impact of comorbidities on immediate post-operative complications in oral cavity free flap patients.

PURPOSE: To examine the relationship between comorbidities and the development of immediate post-operative complications in patients undergoing oral cavity composite resection (OCCR) with free flap (FF) reconstruction. MATERIALS AND METHODS: Retrospective analysis was completed on all consecutive OCCRs with FF reconstruction performed at a single quaternary care facility between 1999 and 2020. Comorbidities, immediate post-operative complications, patient demographics, and tumor characteristics were collected. Odds ratios (OR) with 95 % confidence intervals were calculated for associations between comorbidities and immediate post-operative complications. RESULTS: 320 patients who underwent OCCR with FF reconstruction were included. One hundred twenty-one (37.8 %) patients developed a post-operative complication during their initial hospital admission. The most common complications were non-pneumonia cardiopulmonary events (14.1 %), pneumonia (9.4 %), and wound infection (8.4 %). Other complications included flap compromise, bleeding, and fistula. On multivariate analysis, patients without comorbid conditions were less likely to develop a post-operative complication (OR 0.64; 0.41-0.98). Atrial fibrillation (OR 2.94; 1.17-7.39) and cerebrovascular disease (OR 2.28; 1.08-4.84) were associated with increased odds of developing any complications. Furthermore, cerebrovascular disease (OR: 2.33; 1.04-5.39) and peripheral vascular disease (OR: 2.7; 1.2-6.08) were independently associated with pneumonia. CONCLUSION: In this retrospective review of patients undergoing OCCR with FF reconstruction for oral cavity SCC, lack of identifiable comorbidities appeared to be protective for post-operative complications while atrial fibrillation and cerebrovascular disease were associated with increased odds of any complication. Pre-existing vascular disease was also associated with an increased risk of pneumonia.

Addressing Barriers and Facilitators to African Americans' and Hispanics' Participation in Clinical and Genomic Research Through a Bioethical Sensitive Video.

Research advances on effective methods to prevent, diagnose, and treat cancer continue to emerge through clinical and genomic research. Most clinical trial and genomic research participants identify as White which limits the generalizability of research findings to non-White populations. With the development and access to technology, digital delivery of salient and tailored health education may provide innovative pathways to increase representation of African Americans (AA) and Hispanics in research. This project focused on the creation of a bioethical sensitive education video aimed at increasing participation in clinical trials and genomic research by bringing together experts from the community, healthcare, biomedical research, and public health. The goal was to utilize existing educational resources to create a tailored message to address AA/Hispanics' beliefs, values, and bioethical concerns related to participation in clinical and genomic research. Models of behavior change and communication theories were leveraged to frame key components of the message, which then informed the framework for the animated video. Development of the video consisted of six iterative phases: 1) writing sessions; 2) storyboarding; 3) animating; 4) screening/revisions; 5) acceptability testing; 6) finalization. The final animated video is approximately 5 min in length and covers several topics including the goal of clinical research, disparities in research participation, bioethical concerns, and genomic research regulations. Increasing AA and Hispanic participation in clinical and genomic research is imperative to achieving health equity. Tailored messages via short videos may assist in addressing the barriers and facilitators towards research participation and increase intentions to enroll in trials.

The Bead Maze Hand Function Test for Children.

IMPORTANCE: There is a need for a pediatric hand function test that can be used to objectively assess movement quality. We have developed a toy-based test, the Bead Maze Hand Function (BMHF) test, to quantify how well a child performs an activity. This is achieved by assessing the control of forces applied while drawing a bead over wires of different complexity. OBJECTIVE: To study the psychometric properties of the BMHF test and understand the influence of age and task complexity on test measures. DESIGN: A cross-sectional, observational study performed in a single visit. SETTING: Clinical research laboratory. PARTICIPANTS: Twenty-three participants (ages 4-15 yr) were recruited locally. They were typically developing children with no illness or conditions that affected their movement. Interventions/Assessments: Participants performed the BMHF test and the Box and Block test with both hands. OUTCOMES AND MEASURES: Total force and completion time were examined according to age and task complexity using a linear mixed-effects model. We calculated intraclass correlation coefficients to measure interrater reliability of the method and estimated concurrent validity using the Box and Block test. RESULTS: Total force and completion time decreased with age and depended on task complexity. The total force was more sensitive to task complexity. The Box and Block score was associated with BMHF completion time but not with total force. We found excellent interrater reliability. CONCLUSIONS AND RELEVANCE: A familiar toy equipped with hidden sensors provides a sensitive tool to assess a child's typical hand function. Plain-Language Summary: We developed the Bead Maze Hand Function (BMHF) test to determine how well a child performs an activity with their hands. The BMHF test is a toy equipped with hidden sensors. Twenty-three typically developing children with no illnesses or conditions that affected their hand movement participated in the study. We asked the children to perform the BMHF test with both hands. Our study found that occupational therapists can reliably use the BMHF test to assess a child's hand function.

Yeast life span extension by depletion of 60s ribosomal subunits is mediated by Gcn4.

In nearly every organism studied, reduced caloric intake extends life span. In yeast, span extension from dietary restriction is thought to be mediated by the highly conserved, nutrient-responsive target of rapamycin (TOR), protein kinase A (PKA), and Sch9 kinases. These kinases coordinately regulate various cellular processes including stress responses, protein turnover, cell growth, and ribosome biogenesis. Here we show that a specific reduction of 60S ribosomal subunit levels slows aging in yeast. Deletion of genes encoding 60S subunit proteins or processing factors or treatment with a small molecule, which all inhibit 60S subunit biogenesis, are each sufficient to significantly increase replicative life span. One mechanism by which reduced 60S subunit levels leads to life span extension is through induction of Gcn4, a nutrient-responsive transcription factor. Genetic epistasis analyses suggest that dietary restriction, reduced 60S subunit abundance, and Gcn4 activation extend yeast life span by similar mechanisms.

Presence of refractory GERD-like symptoms following laparoscopic fundoplication is rarely indicative of true recurrent GERD.

BACKGROUND: Laparoscopic fundoplication (LF) is the gold standard for gastroesophageal reflux disease (GERD). Recurrent GERD is a known complication; however, the incidence of recurrent GERD-like symptoms and long-term fundoplication failure is rarely reported. Our objective was to identify the rate of recurrent pathologic GERD in patients with GERD-like symptoms following fundoplication. We hypothesized that patients with recurrent GERD-like symptoms refractory to medical management do not have evidence of fundoplication failure as indicated by a positive ambulatory pH study. METHODS: This is a retrospective cohort study of 353 consecutive patients undergoing LF for GERD between 2011 and 2017. Baseline demographics, objective testing, GERD-HRQL scores, and follow-up data were collected in a prospective database. Patients with return visits to clinic following routine post-operative visits were identified (n = 136, 38.5%), and those with a primary complaint of GERD-like symptoms (n = 56, 16%) were included. The primary outcome was the proportion of patients with a positive post-operative ambulatory pH study. Secondary outcomes included proportion of patients with symptoms managed with acid-reducing medications, time to return to clinic, and need for reoperation. P values < 0.05 were considered significant. RESULTS: Fifty-six (16%) patients returned during the study period for an evaluation of recurrent GERD-like symptoms with a median interval of 51.2 (26.2-74.7) months. Twenty-four patients (42.9%) were successfully managed expectantly or with acid-reducing medications. Thirty two (57.1%) presented with GERD-like symptoms and failure of management with medical acid suppression and underwent repeat ambulatory pH testing. Of these, only 5 (9%) were found to have a DeMeester score of > 14.7, and three (5%) underwent recurrent fundoplication. CONCLUSION: Following LF, the incidence of GERD-like symptoms refractory to PPI therapy is much higher than the incidence of recurrent pathologic acid reflux. Few patients with recurrent GI symptoms require surgical revision. Evaluation, including objective reflux testing, is critical to evaluating these symptoms.

Ouratea spectabilis and its Biflavanone Ouratein D Exert Potent Anti-inflammatory Activity in MSU Crystal-induced Gout in Mice.

Gouty arthritis (GA) is an inflammatory arthritis triggered by the deposition of monosodium urate monohydrate (MSU) crystals, causing pain, inflammation, and joint damage. Several drugs are currently employed to manage acute flares of GA, but they either have limited effectiveness or induce severe adverse reactions. Ouratea spectabilis is traditionally used in Brazil to treat gastric ulcers and rheumatism. The ethanolic extract of O. spectabilis stems (OSpC) and four biflavanones (ouratein A - D) isolated thereof were evaluated in a murine model of GA induced by the injection of MSU crystals. The underlying mechanism of action of ouratein D was investigated in vitro in cell cultures by measurement of IL-1ß levels by ELISA and Western blot analysis. The administration of OSpC (10, 30 or 100 mg/Kg, p. o.) reduced the migration of total inflammatory cells, monocytes, and neutrophils and diminished the levels of IL-1ß and CXCL1 in the synovial tissue. Among the tested compounds, only ouratein D (1 mg/Kg) reduced the migration of the inflammatory cells and it was shown to be active up to 0.01 mg/Kg (equivalent to 0.34 nM/Kg, p. o.). Treatment of pre-stimulated THP-1 cells (differentiated into macrophages) or BMDMs with ouratein D reduced the release of IL-1ß in both macrophage lines. This biflavanone reduced the activation of caspase-1 (showed by the increase in the cleaved form) in supernatants of cultured BMDMs, evidencing its action in modulating the inflammasome pathway. The obtained results demonstrate the anti-gout properties of O. spectabilis and point out ouratein D as the bioactive component of the assayed extract.

Changes in Health Care Utilization and Associated Costs After Supportive Housing Placement by an Urban Community Mental Health Center.

Permanent supportive housing (PSH) for individuals experiencing homelessness and living with mental illness can reduce utilization of crisis care services and increase utilization of outpatient care, although the extent to which pre-housing utilization patterns influence post-housing utilization remains unclear. Therefore, pre- and post-housing health service utilization was examined in 80 individuals living with a chronic mental illness who were and were not utilizing health care services in the years pre- and post-housing. Overall, the proportion of tenants utilizing outpatient services, including outpatient behavioral health services, increased from pre- to post-housing. Tenants who did not use outpatient behavioral health services prior to housing were disproportionately less likely than their peers to use those services after being housed. Among tenants who utilized crisis care services prior to being housed, reductions were observed in the number of crisis care visits. Results suggest PSH leads to changes in health care utilization and associated costs.

Neonatal screening for spinal muscular atrophy: A pilot study in Brazil.

Spinal muscular atrophy (SMA) is considered one of the most common autosomal recessive disorders, with an estimated incidence of 1 in 10,000 live births. Testing for SMA has been recommended for inclusion in neonatal screening (NBS) panels since there are several therapies available and there is evidence of greater efficacy when introduced in the pre/early symptomatic phases. In Brazil, the National Neonatal Screening Program tests for six diseases, with a new law issued in 2021 stating that it should incorporate more diseases, including SMA. In the present study, dried blood spot (DBS) samples collected by the Reference Services of Neonatal Screening of RS and SP, to perform the conventional test were also screened for SMA, using real-time PCR, with SALSA MC002 technique. A total of 40,000 samples were analyzed, enabling the identification of four positive cases of SMA, that were confirmed by MLPA. Considering our sampling, Brazil seems to have an incidence comparable to the described in other regions. This work demonstrated that the use of the MC002 technique in samples routinely collected for the conventional NBS program is suitable to screen for SMA in our conditions and can be included in the expansion of the neonatal screening programs.

Systemic follicular lymphoma in a patient with a history of thyroid eye disease: a case report.

The most common cause of both unilateral and bilateral proptosis in adults is thyroid eye disease (TED), and the diagnosis in typical cases is made without imaging. However, many other orbital diseases, including inflammatory, infectious, and neoplastic processes, can mimic the symptoms of thyroid eye disease, highlighting the importance of imaging and biopsy in challenging cases. There are limited reports in the literature of orbital lymphoma being diagnosed in patients with a history of thyroid eye disease. Here, we present the case of a patient with long-standing TED who developed new asymmetric proptosis and was subsequently diagnosed with systemic follicular lymphoma.

Survival Analysis Using Albumin-Bilirubin (ALBI) Grade for Patients Treated with Drug-Eluting Embolic Transarterial Chemoembolization for Hepatocellular Carcinoma.

PURPOSE: The albumin-bilirubin (ALBI) grade has been established as an improved predictor of survival in patients with hepatocellular carcinoma (HCC) treated with conventional transarterial chemoembolization and yttrium-90 radioembolization. The purpose of the study was to investigate the utility of ALBI grade in prognosticating outcomes in patients with HCC treated with drug-eluting embolic (DEE) transarterial chemoembolization (TACE). MATERIALS AND METHODS: A single-center retrospective review was performed to compare the efficacy of ALBI grade and Child-Pugh (CP) classification in predicting the survival of patients with HCC receiving DEE-TACE. A total of 303 patients with HCC were identified who had received DEE-TACE without concomitant locoregional therapy within 30 days. Survival analysis was performed using Kaplan-Meier methods and censored for curative therapy. Survival curves were stratified based on the ALBI grade, CP class, Barcelona Clinic Liver Cancer (BCLC) stage, Eastern Cooperative Oncology Group performance status, and presence of ascites. The discriminatory ability of survival curves was calculated by C-Index. RESULTS: Kaplan-Meier survival curves stratified by the ALBI grade produced distinct, nonoverlapping curves (P < .001), showing greater discriminatory ability than the CP classification (C-index = 0.568 and 0.545, respectively). The substratification of the BCLC stage by the ALBI grade yielded greater discriminatory ability than the substratification by the CP classification (C-index = 0.573 and 0.565, respectively). For patients with BCLC stage B, the substratification by the ALBI grade yielded distinct curves, whereas the substratification by the CP classification did not (P = .011 and P = .379, respectively). CONCLUSIONS: ALBI grade showed improved discriminatory ability compared with CP classification in differentiating overall survival among patients with HCC receiving DEE-TACE. Furthermore, ALBI grade was effective in substratifying survival among patients categorized as CP class A and patients with BCLC stage B, whereas CP classification was not effective.

Contemporary Management of Acute Pulmonary Embolism: Evolution of Catheter-based Therapy.

Acute pulmonary embolism (PE) affects more than 100 000 people in the United States annually and is the third leading cardiovascular cause of death. The standard management for PE is systemic anticoagulation therapy. However, a subset of patients experience hemodynamic decompensation, despite conservative measures. Traditionally, these patients have been treated with systemic administration of thrombolytic agents or open cardiac surgery, although attempts at endovascular treatment have a long history that dates back to the 1960s. The technology for catheter-based therapy for acute PE is rapidly evolving, with multiple devices approved over the past decade. Currently available devices fall into two broad categories of treatment methods: catheter-directed thrombolysis and percutaneous suction thrombectomy. Catheter-directed thrombolysis is the infusion of thrombolytic agents directly into the occluded pulmonary arteries to increase local delivery and decrease the total dose. Suction thrombectomy involves the use of small- or large-bore catheters to mechanically aspirate a clot from the pulmonary arteries without the need for a thrombolytic agent. A thorough understanding of the various risk stratification schemes and the available evidence for each device is critical for optimal treatment of this complex entity. Multiple ongoing studies will improve our understanding of the role of catheter-based therapy for acute PE in the next 5-10 years. A multidisciplinary approach through PE response teams has become the management standard at most institutions. An invited commentary by Bulman and Weinstein is available online. Online supplemental material is available for this article. ©RSNA, 2022.

The oldest unvaccinated Covid-19 survivors in South America.

BACKGROUND: Although older adults are at a high risk of severe or critical Covid-19, there are many cases of unvaccinated centenarians who had a silent infection or recovered from mild or moderate Covid-19. We studied three Brazilian supercentenarians, older than 110 years, who survived Covid-19 in 2020 before being vaccinated. RESULTS: Despite their advanced age, humoral immune response analysis showed that these individuals displayed robust levels of IgG and neutralizing antibodies (NAbs) against SARS-CoV-2. Enrichment of plasma proteins and metabolites related to innate immune response and host defense was also observed. None presented autoantibodies (auto-Abs) to type I interferon (IFN). Furthermore, these supercentenarians do not carry rare variants in genes underlying the known inborn errors of immunity, including particular inborn errors of type I IFN. CONCLUSION: These observations suggest that their Covid-19 resilience might be a combination of their genetic background and their innate and adaptive immunity.

What do people find most meaningful? How representations of the self and the world provide meaning in life.

OBJECTIVE: Recent theories propose that global meaning in life (MIL) is based on feelings of coherence, purpose, and existential mattering. MIL has also been linked to mental representations-for example, beliefs, values, attitudes, and identities-that serve as "meaning frameworks" for interpreting the world and oneself. Combining these proposals, we predicted that beliefs, values, attitudes, and identities would foster a sense of MIL to the extent that they provide feelings of coherence, purpose, and existential mattering. METHOD: Using multilevel path analysis, we tested within-person associations of coherence, purpose, and existential mattering with a sense of MIL across three studies (Study 1:208 US MTurk workers; Study 2:106 UK university students; Study 3:296 from a UK nationally representative Prolific sample). We explored the generality of these associations across mental representation types and individual differences. RESULTS: Participants derived greater MIL most strongly from mental representations that provided sense of purpose, followed by existential mattering. Sense of coherence was less robustly related to MIL across mental representation types and religious orientation. CONCLUSIONS: Integrating prior theorizing on MIL, we conclude that mental representations function as "meaning frameworks" to the extent that they provide feelings of purpose, mattering, and, sometimes, coherence.

Proximal and distal honor fit and subjective well-being in the Mediterranean region.

OBJECTIVE: People's psychological tendencies are attuned to their sociocultural context and culture-specific ways of being, feeling, and thinking are believed to assist individuals in successfully navigating their environment. Supporting this idea, a stronger "fit" with one's cultural environment has often been linked to positive psychological outcomes. The current research expands the cultural, conceptual, and methodological space of cultural fit research by exploring the link between well-being and honor, a central driver of social behavior in the Mediterranean region. METHOD: Drawing on a multi-national sample from eight countries circum-Mediterranean (N = 2257), we examined the relationship between cultural fit in honor and well-being at the distal level (fit with one's perceived society) using response surface analysis (RSA) and at the proximal level (fit with one's university gender group) using profile analysis. RESULTS: We found positive links between fit and well-being in both distal (for some, but not all, honor facets) and proximal fit analyses (across all honor facets). Furthermore, most fit effects in the RSA were complemented with positive level effects of the predictors, with higher average honor levels predicting higher well-being. CONCLUSIONS: Our findings highlight the interplay between individual and environmental factors in honor as well as the important role honor plays in well-being in the Mediterranean region.

A qualitative analysis of perceptions of and reactions to COVID-19.

OBJECTIVE: To understand communities' perceptions, beliefs, and health-related behavior choices related to COVID-19 in order to guide public health nursing communication and interaction with patients and the community. DESIGN: A qualitative study, guided by the Health Belief Model (HBM), strove to comprehend the perceptions and reactions to COVID-19 among Wisconsinites. SAMPLE: Twenty-five diverse Wisconsin residents aged 18 or older. MEASUREMENTS: Semi-structured interviews provided information about individuals' attitudes, perceptions, and reactions to COVID-19. Interviews were audio-recorded, transcribed, and thematic analysis was conducted to identify themes. RESULTS: We identified three major themes: (1) "health care starts way before you ever enter the doors of a healthcare facility"; (2) "to live in a society is to help each other"; and (3) mental health as impacted by COVID-19. CONCLUSIONS: This study demonstrated the need for greater public health support, as well as the role of Social Determinants of Health. Understanding perceptions and reactions to COVID-19 can help public health nurses understand and better respond to future pandemics.

Different Food Sources of Fructose-Containing Sugars and Fasting Blood Uric Acid Levels: A Systematic Review and Meta-Analysis of Controlled Feeding Trials.

BACKGROUND: Although fructose as a source of excess calories increases uric acid, the effect of the food matrix is unclear. OBJECTIVES: To assess the effects of fructose-containing sugars by food source at different levels of energy control on uric acid, we conducted a systematic review and meta-analysis of controlled trials. METHODS: MEDLINE, Embase, and the Cochrane Library were searched (through 11 January 2021) for trials ≥ 7 days. We prespecified 4 trial designs by energy control: substitution (energy-matched replacement of sugars in diets); addition (excess energy from sugars added to diets); subtraction (energy from sugars subtracted from diets); and ad libitum (energy from sugars freely replaced in diets) designs. Independent reviewers (≥2) extracted data and assessed the risk of bias. Grading of Recommendations, Assessment, Development, and Evaluation was used to assess the certainty of evidence. RESULTS: We included 47 trials (85 comparisons; N = 2763) assessing 9 food sources [sugar-sweetened beverages (SSBs), sweetened dairy, fruit drinks, 100% fruit juice, fruit, dried fruit, sweets and desserts, added nutritive sweetener, and mixed sources] across 4 energy control levels in predominantly healthy, mixed-weight adults. Total fructose-containing sugars increased uric acid levels in substitution trials (mean difference, 0.16 mg/dL;  95% CI:  0.06-0.27 mg/dL;  P = 0.003), with no effect across the other energy control levels. There was evidence of an interaction by food source: SSBs and sweets and desserts increased uric acid levels in the substitution design, while SSBs increased and 100% fruit juice decreased uric acid levels in addition trials. The certainty of evidence was high for the increasing effect of SSBs in substitution and addition trials and the decreasing effect of 100% fruit juice in addition trials and was moderate to very low for all other comparisons. CONCLUSIONS: Food source more than energy control appears to mediate the effects of fructose-containing sugars on uric acid. The available evidence provides reliable indications that SSBs increase and 100% fruit juice decreases uric acid levels. More high-quality trials of different food sources are needed. This trial was registered at clinicaltrials.gov as NCT02716870.

Simple models highlight differences in the walking biomechanics of young children and adults.

Adults conserve metabolic energy during walking by minimizing the step-to-step transition work performed by the legs during double support and by utilizing spring-like mechanisms in their legs, but little is known as to whether children utilize these same mechanisms. To gain a better understanding, we studied how children (5-6 years) and adults modulate the mechanical and metabolic demands of walking at their preferred speed, across slow (75%), preferred (100%) and fast (125%) step frequencies. We quantified (1) the positive mass-specific work done by the trailing leg during step-to-step transitions and (2) the leg's spring-like behavior during single support. On average, children walked with a 36% greater net cost of transport (COT; J kg-1 m-1) than adults (P=0.03), yet both groups increased their net COT at varying step frequencies. After scaling for speed, children generated ∼2-fold less trailing limb positive scaled mechanical work during the step-to-step transition (P=0.02). Unlike adults, children did not modulate their trailing limb positive work to meet the demands of walking at 75% and 125% of their preferred step frequency. In single support, young children operated their stance limb with much greater compliance than adults ( versus 11.35; P=0.023). Our observations suggest that the mechanics of walking in children aged 5-6 years are fundamentally distinct from the mechanics of walking in adults and may help to explain a child's higher net COT. These insights have implications for the design of assistive devices for children and suggest that children cannot be simply treated as scaled-down versions of adults.