Rasch analysis of the modified Fatigue Severity Scale in neuromuscular disorders and comparison between sex, age and diagnoses.

INTRODUCTION/AIMS: Fatigue is a common and debilitating symptom encountered in the neuromuscular clinic. The 7-item Fatigue Severity Scale (FSS-7) is a Rasch-modified assessment validated in inflammatory neuropathies but not across a typical neuromuscular patient population. The aim of this study was to validate this measure in neuromuscular disorders and to compare between patient sex, age and diagnoses. METHODS: The modified FSS-7 was mailed to patients recruited from a specialist neuromuscular clinic at the Walton Centre. Responses were subjected to Rasch analysis and descriptive statistics were performed on the Rasch converted data. RESULTS: The mFSS-7 met the Rasch model expectations with an overall Chi-square probability of 0.4918, a strict unidimensional scale free from differential item functioning (DIF) that satisfied the model with substantial test-retest reliability using Lin's concordance correlation coefficient 0.71 (95% CI 0.63-0.77). A 15.7% ceiling effect was observed in this patient cohort. Post hoc analysis did not show any significant difference in fatigue between sex, age or neuromuscular diagnoses. DISCUSSION: The self-completed Rasch mFSS-7 showed acceptable test-retest reliability across patients with varied disorders under follow-up in a specialist neuromuscular clinic. The ceiling effect constrains its use for those with the most severe fatigue. Future considerations could include assessment of the benefits of clinical interventions, particularly multidisciplinary team input or dedicated fatigue clinics.

A case of olfactory ganglioneuroblastoma in a dog: immunohistochemical comparison with olfactory neuroepithelia and olfactory neuroblastomas.

In the present study, histopathological and immunohistochemical findings of olfactory ganglioneuroblastoma in a dog were compared to those of canine olfactory neuroepithelia and neuroblastomas. Olfactory ganglioneuroblastoma consists of ganglion cell-like tumor cells with Schwannian stroma and neuroblast-like tumor cells. Immunohistochemically, ganglion cell-like tumor cells were immunopositive for synaptophysin, ß3-tubulin, and tyrosine hydroxylase, Schwannian stroma was immunopositive for GFAP and SOX2, and neuroblast-like tumor cells were immunopositive for OLIG2, ß3-tubulin, SOX2, cytokeratin AE1/AE3, and p63. The immunohistochemical results of olfactory neuroepithelia and olfactory neuroblastomas were similar to those of neuroblast-like tumor cells. These results suggest that the ganglion cell-like tumor cells in the present case have a sympathetic neuron immunophenotype, whereas neuroblast-like tumor cells have an olfactory neuroepithelial immunophenotype.

Establishing the origin of Marcus-inverted-region behaviour in the excited-state dynamics of cobalt(III) polypyridyl complexes.

Growing interest in the use of first-row transition metal complexes in a number of applied contexts-including but not limited to photoredox catalysis and solar energy conversion-underscores the need for a detailed understanding of their photophysical properties. A recent focus on ligand-field photocatalysis using cobalt(III) polypyridyls in particular has unlocked unprecedented excited-state reactivities. Photophysical studies on Co(III) chromophores in general are relatively uncommon, and so here we carry out a systematic study of a series of Co(III) polypyridyl complexes in order to delineate their excited-state dynamics. Compounds with varying ligand-field strengths were prepared and studied using variable-temperature ultrafast transient absorption spectroscopy. Analysis of the data establishes that the ground-state recovery dynamics are operating in the Marcus inverted region, in stark contrast to what is typically observed in other first-row metal complexes. The analysis has further revealed the underlying reasons driving this excited-state behaviour, thereby enabling potential advancements in the targeted use of the Marcus inverted region for a variety of photolytic applications.

Comparison of Surgical Modalities for Giant Pituitary Adenoma: A Systematic Review and Meta-Analysis of 1413 Patients.

BACKGROUND AND OBJECTIVES: Giant pituitary adenomas (GPAs) are a challenging clinical entity, composing 5% to 15% of all pituitary adenomas. While the endoscopic endonasal transsphenoidal (EET) approach has surpassed the microsurgical transsphenoidal (MT) and transcranial (TC) approaches as the first-line surgical modality in most institutions, a systematic review comparing the 3 approaches has not been undertaken since 2012. Given growing adoption of EET and development of novel operative techniques over the past decade, an updated comparison of GPA surgical modalities is warranted. METHODS: We identified all studies related to the surgical management of GPAs in PubMed, Embase, and Web of Science from inception to December 31, 2021. End points assessed included gross total resection (GTR) rates, postoperative visual improvement, mortality, and perioperative complications. RESULTS: After screening of 1701 studies, we identified 45 studies on the surgical management of GPAs for meta-analysis. Thirty-one used the EET approach (n = 1413), 11 studies used the MT approach (n = 601), and 10 used the TC approach (n = 416). The cumulative number of patients treated by EET did not exceed that of patients treated by the TC or MT approaches until 2014 and 2015, respectively. Despite patients undergoing EET having the highest average tumor diameter, pooled rates for GTR were significantly higher for EET (42%) than MT (33%, P < .001) and TC (8%, P < .001) and EET similarly exhibited superior rates of visual improvement (85%) than MT (73%, P < .001) and TC (56%, P < .001). Mortality rates were comparable between EET (0.6%) and MT (1.6%), but EET had significantly lower mortality than TC (2.7%, P < .001). Compared with MT, EET had lower rates of hypopituitarism (8.5% vs 14.9%, P = .012) but higher rates of diabetes insipidus (3.1% vs 0.5%, P = .001). CONCLUSION: In an updated meta-analysis of 1413 patients with GPA, EET resection conferred significantly higher rates of visual improvement and GTR, when compared with the MT and TC approaches.

Detection of periodic peaks in Karenia brevis concentration consistent with the time-delay logistic equation.

The logistic equation models single-species population growth with a sigmoid curve that begins as exponential and ends with an asymptotic approach to a final population determined by natural system carrying capacity. But the population of a natural system often does not stabilize as it approaches carrying capacity. Instead, it exhibits periodic change, sometimes with very large amplitudes. The time-delay modification of the logistic equation accounts for this behavior by connecting the present rate of population growth to conditions at an earlier time. The periodic change in population with time can progress from a monotonic approach to the carrying capacity; to oscillation around the carrying capacity; to limit-cycle periodic change; and, finally, to chaotic change. The presence of multiple species and inadequate sampling frequency and spatial coverage hinder the application of the time-delay logistic equation to real-world populations. Blooms of Karenia brevis along the southwest Florida Gulf Coast, however, provide a unique opportunity in that blooms are nearly monospecific and are sampled frequently over a wide geographic region; they are good candidates for testing the time-delay logistic equation. We show that these blooms exhibit peaks in concentration with periods in the range of 40-100 days, consistent with that predicted by the time-delay logistic equation. Cell concentrations in the valleys between the peaks are at least 2-3 orders of magnitude lower than peak values, offering predictable windows of opportunity for potential mitigation efforts.

Efficacy and adverse events of L-Asparaginase administration as a first-line treatment for feline large-cell gastrointestinal lymphoma.

L-Asparaginase (L-Asp) is often used to induce remission in feline large-cell gastrointestinal lymphoma (LCGIL). However, no study has evaluated the efficacy and adverse events following the initial use of this drug as a first-line treatment in feline LCGIL. We retrospectively reviewed medical records of cats with LCGIL treated with L-Asp to induce remission. This study included 43 cats. The response rate (RR) after the first administration of L-Asp was 37.2% (Complete remission: 7.0%, partial remission: 30.2%). RR was significantly higher in cases with primary gastric lesions (64.3%) than in those with primary intestinal lesions (24.1%) (P=0.018), and it was also higher in cases without anemia (57.1%) than those with anemia (15.0%) (P=0.009). The most common adverse event was hyperammonemia, which occurred in 10 of 12 cases where we could compare plasma ammonia concentrations before and after the first dose of L-Asp. Plasma phosphate concentrations were also significantly increased (P<0.001) within 24 hr after the first dose. Decreased appetite, vomiting, and diarrhea were also observed in five, three, and seven cases, respectively, and Grade 3 or higher gastrointestinal signs were observed as adverse events in three cases. The median overall survival of all cats was 150 days (range, 5-1,065 days), and the median progression-free survival was 104 days (range, 2-978 days). In conclusion, L-Asp was effective to induce remission, and severe adverse events were uncommon in feline LCGIL.

Safety and efficacy of histotripsy delivery through overlying gas-filled small bowel in an ex vivo swine model.

PURPOSE: To evaluate the safety and efficacy of performing histotripsy through overlying gas-filled bowel in an ex vivo swine model. METHODS: An ex vivo model was created to simulate histotripsy treatment of solid organs through gas-filled bowel. Spherical 2.5 cm histotripsy treatments were performed in agar phantoms for each of five treatment groups: 1) control with no overlying bowel (n = 6), 2) bowel 0 cm above phantom (n = 6), 3) bowel 1 cm above phantom (n = 6), 4) bowel 2 cm above phantom (n = 6), and 5) bowel 0 cm above the phantom with increased treatment amplitude (n = 6). Bowel was inspected for gross and microscopic damage, and treatment zones were measured. A ray-tracing simulation estimated the percentage of therapeutic beam path blockage by bowel in each scenario. RESULTS: All histotripsy treatments through partial blockage were successful (24/24). No visible or microscopic damage was observed to intervening bowel. Partial blockage resulted in a small increase in treatment volume compared to controls (p = 0.002 and p = 0.036 for groups with bowel 0 cm above the phantom, p > 0.3 for bowel 1 cm and 2 cm above the phantom). Gas-filled bowel was estimated to have blocked 49.6%, 35.0%, and 27.3% of the therapeutic beam at 0, 1, and 2 cm, respectively. CONCLUSION: Histotripsy has the potential to be applied through partial gas blockage of the therapeutic beam path, as shown by this ex vivo small bowel model. Further work in an in vivo survival model appears indicated.

Cytoplasmic aggregation of TDP43 and topographic correlation with tau and α-synuclein accumulation in the rTg4510 mouse model of tauopathy.

In patients with TDP43 proteinopathy, phosphorylated TDP43 (p-TDP43) accumulates in the cytoplasm of neurons. The accumulation of p-TDP43 has also been reported in patients with tauopathy and α-synucleinopathy. We investigated spatiotemporal changes in p-TDP43 accumulation in the brains of rTg4510 mice that overexpressed human mutant tau (P301L) and exhibited hyperphosphorylated tau (hp-tau) and phosphorylated αSyn (p-αSyn) accumulation. Immunohistochemically, p-TDP43 aggregates were observed in the cytoplasm of neurons, which increased with age. A significant positive correlation was observed between the number of cells with p-TDP43 aggregates and hp-tau and p-αSyn aggregates. Suppression of the human mutant tau (P301L) expression by doxycycline treatment reduces the accumulation of p-TDP43, hp-tau, and p-αSyn. Proteinase K-resistant p-TDP43 aggregates were found in regions with high hp-tau, and p-αSyn accumulation. Western blotting of the sarkosyl-insoluble fraction revealed bands of monomeric TDP43 and p-TDP43. These results indicate that the accumulation of mouse p-TDP43 is associated with the accumulation of human mutant tau (P301L) in rTg4510 mouse brains. The accumulation of hp-tau and p-αSyn may promote sarkosyl-insoluble p-TDP43 aggregates that are resistant to proteinase K. The synergistic effects of tau, TDP43, and αSyn may be involved in the pathology of proteinopathies, leading to the accumulation of multiple abnormal proteins.

Neuropsychiatric Complications of Hypervitaminosis D: Diagnosis, Evaluation, and Treatment.

The Psychiatric Consultation Service at Massachusetts General Hospital sees medical and surgical inpatients with comorbid psychiatric symptoms and conditions. During their twice-weekly rounds, Dr Stern and other members of the Consultation Service discuss diagnosis and management of hospitalized patients with complex medical or surgical problems who also demonstrate psychiatric symptoms or conditions. These discussions have given rise to rounds reports that will prove useful for clinicians practicing at the interface of medicine and psychiatry.Prim Care Companion CNS Disord 2024;26(3):23f03680. Author affiliations are listed at the end of this article.

Harnessing landrace diversity empowers wheat breeding.

Harnessing genetic diversity in major staple crops through the development of new breeding capabilities is essential to ensure food security1. Here we examined the genetic and phenotypic diversity of the A.E. Watkins landrace collection2 of bread wheat (Triticum aestivum), a major global cereal, through whole-genome re-sequencing (827 Watkins landraces and 208 modern cultivars) and in-depth field evaluation spanning a decade. We discovered that modern cultivars are derived from just two of the seven ancestral groups of wheat and maintain very long-range haplotype integrity. The remaining five groups represent untapped genetic sources, providing access to landrace-specific alleles and haplotypes for breeding. Linkage disequilibrium (LD) based haplotypes and association genetics analyses link Watkins genomes to the thousands of high-resolution quantitative trait loci (QTL), and significant marker-trait associations identified. Using these structured germplasm, genotyping and informatics resources, we revealed many Watkins-unique beneficial haplotypes that can confer superior traits in modern wheat. Furthermore, we assessed the phenotypic effects of 44,338 Watkins-unique haplotypes, introgressed from 143 prioritised QTL in the context of modern cultivars, bridging the gap between landrace diversity and current breeding. This study establishes a framework for systematically utilising genetic diversity in crop improvement to achieve sustainable food security.

The utility of procalcitonin for identifying secondary infections in patients with influenza or COVID-19 receiving extracorporeal membrane oxygenation.

Background: Identifying secondary infections in patients receiving extracorporeal membrane oxygenation (ECMO) presents challenges due to the ECMO circuit's influence on traditional signs of infection. Objectives: This study evaluates procalcitonin as a diagnostic marker for secondary infections in patients receiving ECMO with influenza or COVID-19 infection. Design: Single-center retrospective cohort study. Methods: All adult patients receiving veno-venous ECMO with underlying influenza or COVID-19 from November 2017 to October 2021 were included. Patient demographics, time receiving ECMO, culture data, and procalcitonin levels were examined. The first procalcitonin within 3 days of infection was compared to negative workups that were collected at least 10 days from the last positive culture. Furthermore, we compared procalcitonin levels by the type of pathogen and site of infection. Results: In this study, 84 patients with influenza or COVID-19 who received ECMO were included. A total of 276 procalcitonin labs were ordered in this cohort, with 33/92 (36%) of the secondary infections having an associated procalcitonin value. When comparing procalcitonin levels, there was no significant difference between the infection and negative workup groups [1 ng/mL (interquartile ranges, IQR: 0.4-1.2) versus 1.3 (0.5-4.3), p = 0.19]. Using 0.5 ng/mL as the cut-off, the sensitivity of procalcitonin was 67% and the specificity was 30%. In our cohort, the positive predictive value of procalcitonin was 14.5% and the negative predictive value was 84%. There was no difference in procalcitonin by type of organism or site of infection. Procalcitonin levels did not routinely decline even after an infection was identified. Conclusion: While procalcitonin is a proposed potential diagnostic marker for secondary infections in patients receiving ECMO, this single-center study demonstrated low sensitivity and specificity of procalcitonin in identifying secondary infections. Furthermore, there was no association of procalcitonin levels with etiology of infection when one was present. Procalcitonin should be used cautiously in identifying infections in veno-venous ECMO.

BACKGROUND: It is very difficult to determine whether patients receiving ECMO have infections as both vital signs and laboratory markers have not shown good utility. Procalcitonin is a laboratory test sometimes used to identify infections, but its test performance is not known in this population. METHODS: We performed a study of adult patient patients receiving ECMO to determine if there were differences in procalcitonin levels when patients had infections as compared to when they did not have infections. We also looked to see if procalcitonin levels routinely dropped after an infection was diagnosed. RESULTS: Procalcitonin values were no different when patients had an infection as compared to when they did not have an infection. Using standard laboratory cut-offs, the procalcitonin sensitivity was 67%, and specificity was 30%. Procalcitonin levels did not routinely decline even after an infection was identified. CONCLUSIONS: Procalcitonin poorly differentiated patients with infections from those without infections and should be used with caution in patients receiving ECMO.

The utility of procalcitonin for identifying secondary infections in patients with influenza or COVID-19 receiving extracorporeal membrane oxygenation Aim: To determine if procalcitonin performs well as a diagnostic marker in identifying additional infections in adult patients receiving ECMO with influenza or COVID-19.

Could 'Isochoric Freezing' Revolutionise Food Preservation?

The present article responds to the food engineering community's growing interest in an emerging and lauded approach to food preservation, popularised by its developers as 'isochoric freezing'. A strong campaign in the scientific literature and mass media has recently promoted this technique as a universal replacement for traditional food freezing and the frozen supply chain by highlighting a number of alleged advantages of 'isochoric freezing'. Some of these claims therefore require a more neutral and critical assessment against the background of the today's state of the art in food freezing technologies. Hence, this article spotlights several concerns regarding the plausibility, energy expenditure, resource efficiency, process rate, throughput and safety of 'isochoric freezing', as well as the correct use of food refrigeration terminology. The aspects considered are intended to make food scientists, technologists and engineers more aware of the real capabilities and the application perspectives of this still immature mode of refrigerated food processing.

(S)-2-Carb-oxy-ethyl l-cysteinyl sulfone.

The title compound {systematic name: (2S)-2-aza-niumyl-3-[(2-carb-oxy-ethane)-sulfon-yl]propano-ate}, C6H11NO6S, forms enanti-opure crystals in the monoclinic space group P21 and exists as a zwitterion, with a protonated α-amino group and a deprotonated α-carboxyl group. Both the carboxyl groups and the amino group are involved in an extensive multicentered inter-molecular hydrogen-bonding scheme. In the crystal, the diperiodic network of hydrogen bonds propagates parallel to (101) and involves inter-connected heterodromic R 4 3(10) rings. Electrostatic forces are major contributors to the structure energy, which was estimated by DFT calculations as E total = -333.5 kJ mol-1.

Social Determinants of Health and Outcomes After Pediatric Ventricular Assist Device Implantation.

BACKGROUND: Limited research exists on the influence of social determinants of health (SDOH) on outcomes in pediatric patients with advanced heart failure receiving mechanical circulatory support. METHODS: Linkage of the Pediatric Interagency Registry for Mechanical Circulatory Support (Pedimacs) and Society of Thoracic Surgeon's Congenital Heart Surgery Database (STS-CHSD) identified pediatric patients who underwent ventricular assist device (VAD) implantation from 2012 to 2022 with available residential zip codes. Utilizing the available zip codes, each patient was assigned a Childhood Opportunity Index (COI) score. Level of childhood opportunity, race, and insurance type were used as proxies for SDOH. Major outcomes included death, transplant, alive with device, and recovery. Secondary outcomes were adverse events. Statistical analyses were performed using the Kaplan-Meier survival, competing risk analyses, and multivariable Cox proportional hazards model. RESULTS: Three hundred seventeen patients were included in the study. Childhood opportunity level and insurance status did not significantly impact morbidity or mortality after VAD implantation. White race was associated with reduced 1-year survival (71% in White vs. 87% in non-White patients, p = 0.05) and increased risk of pump thrombosis (p = 0.02). CONCLUSION: Childhood opportunity level and insurance status were not linked to morbidity and mortality in pediatric patients after VAD implantation. Notably, White race was associated with higher mortality rates. The study underscores the importance of considering SDOH in evaluating advanced therapies for pediatric heart failure and emphasizes the need for accurate socioeconomic data collection in future studies and national registries.

Same-sex sexual behaviour among mammals is widely observed, yet seldomly reported: Evidence from an online expert survey.

Same-sex sexual behaviour (SSSB) occurs in most animal clades, but published reports are largely concentrated in a few taxa. Thus, there remains a paucity of published reports for most mammalian species. We conducted a cross-sectional expert survey to better understand the underlying reasons for the lack of publications on this topic. Most respondents researched Primates (83.6%, N = 61), while the rest studied Carnivora (6.9%, N = 5), Rodentia (4.1%, N = 3), Artiodactyla (2.7%, N = 2), and Proboscidea (2.7%, N = 2). Most respondents (76.7%, N = 56) had observed SSSB in their study species, but only 48.2% (N = 27) collected data on SSSB, and few (18.5%, N = 5) had published papers on SSSB. Of the unique species identified as engaging in SSSB in the survey, 38.6% (N = 17) have no existing reports of SSSB to the knowledge of the authors. In both the survey questions and freeform responses, most respondents indicated that their lack of data collection or publication on SSSB was because the behaviours were rare, or because it was not a research priority of their lab. No respondents reported discomfort or sociopolitical concerns at their university or field site as a reason for why they did not collect data or publish on SSSB. Multiple logistic regressions were performed to assess whether taxa studied, education level, or identification within the LGBTQ+ community predicted observing, collecting data on, or publishing on SSSB, but none of these variables were significant predictors. These results provide preliminary evidence that SSSB occurs more frequently than what is available in the published record and suggest that this may be due to a publishing bias against anecdotal evidence.

Autotrophic adaptive laboratory evolution of the acetogen Clostridium autoethanogenum delivers the gas-fermenting strain LAbrini with superior growth, products, and robustness.

Microbes able to convert gaseous one-carbon (C1) waste feedstocks are increasingly important to transition to the sustainable production of renewable chemicals and fuels. Acetogens are interesting biocatalysts since gas fermentation using Clostridium autoethanogenum has been commercialised. However, most acetogen strains need complex nutrients, display slow growth, and are not robust for bioreactor fermentations. In this work, we used three different and independent adaptive laboratory evolution (ALE) strategies to evolve the wild-type C. autoethanogenum to grow faster, without yeast extract and to be robust in operating continuous bioreactor cultures. Multiple evolved strains with improved phenotypes were isolated on minimal media with one strain, named "LAbrini", exhibiting superior performance regarding the maximum specific growth rate, product profile, and robustness in continuous cultures. Whole-genome sequencing of the evolved strains identified 25 mutations. Of particular interest are two genes that acquired seven different mutations across the three ALE strategies, potentially as a result of convergent evolution. Reverse genetic engineering of mutations in potentially sporulation-related genes CLAU_3129 (spo0A) and CLAU_1957 recovered all three superior features of our ALE strains through triggering significant proteomic rearrangements. This work provides a robust C. autoethanogenum strain "LAbrini" to accelerate phenotyping and genetic engineering and to better understand acetogen metabolism.

Waitlist Outcomes for Pediatric Heart Transplantation in the Current Era: An Analysis of the Pediatric Heart Transplant Society Database.

BACKGROUND: Waitlist mortality (WM) remains elevated in pediatric heart transplantation. Allocation policy is a potential tool to help improve WM. This study aims to identify patients at highest risk for WM to potentially inform future allocation policy changes. METHODS: The Pediatric Heart Transplant Society database was queried for patients <18 years of age indicated for heart transplantation between January 1, 2010 to December 31, 2021. Waitlist mortality was defined as death while awaiting transplant or removal from the waitlist due to clinical deterioration. Because WM is low after the first year, analysis was limited to the first 12 months on the heart transplant list. Kaplan-Meier analysis and log-rank testing was conducted to compare unadjusted survival between groups. Cox proportional hazard models were created to determine risk factors for WM. Subgroup analysis was performed for status 1A patients based on body surface area (BSA) at time of listing, cardiac diagnosis, and presence of mechanical circulatory support. RESULTS: In total 5974 children met study criteria of which 3928 were status 1A, 1012 were status 1B, 963 were listed status 2, and 65 were listed status 7. Because of the significant burden of WM experienced by 1A patients, further analysis was performed in only patients indicated as 1A. Within that group of patients, those with smaller size and lower eGFR had higher WM, whereas those patients without congenital heart disease or support from a ventricular assist device (VAD) at time of listing had decreased WM. In the smallest size cohort, cardiac diagnoses other than dilated cardiomyopathy were risk factors for WM. Previous cardiac surgery was a risk factor in the 0.3 to 0.7 m2 and >0.7 m2 BSA groups. VAD support was associated with lower WM other than in the single ventricle cohort, where VAD was associated with higher WM. Extracorporeal membrane oxygenation and mechanical ventilation were associated with increased risk of WM in all cohorts. CONCLUSIONS: There is significant variability in WM among status-1A patients. Potential refinements to current allocation system should factor in the increased WM risk we identified in patients supported by extracorporeal membrane oxygenation or mechanical ventilation, single ventricle congenital heart disease on VAD support and small children with congenital heart disease, restrictive cardiomyopathy, or hypertrophic cardiomyopathy.

Rasch analysis of the Unidimensional Self-Efficacy Scale in Neuromuscular Disorders and comparison between sex, age, and diagnoses.

INTRODUCTION/AIMS: Self-efficacy reflects a person's perceptions of their capabilities for specific tasks and influences motivation and performance. The Unidimensional Self-Efficacy in Neuromuscular Disorders (USE-NM) was modified from the Multiple Sclerosis (MS) USE-MS scale and administered to patients attending a specialist neuromuscular clinic. The aim was to investigate this measure in neuromuscular disorders and to compare between patient sex, age, and diagnosis. METHODS: The USE-NM was posted to patients recruited from a specialist neuromuscular clinic at the Walton Centre. Responses were subjected to Rasch analysis using RUMM2030 software and descriptive statistics were performed using SPSS version 28. RESULTS: One hundred and ninety-eight patients (56.1% male) grouped by age (<50; 50-59; 60-69; and >69 years) and with varied NM disorders returned the USE-NM. It did not meet the Rasch model expectations due to disordered thresholds of items 6 and 8 ("Sometimes I feel inadequate as a person because of my neuromuscular disorder" and "I feel that my social life would be better if I did not have a neuromuscular disorder"). Following item re-scoring, the modified USE-NM satisfied the Rasch model with a unidimensional scale free from differential item functioning and an overall chi-square probability of 0.146 with good reliability and validity. Post hoc nonparametric testing showed no significant difference in fatigue between sex, age, and neuromuscular diagnoses. DISCUSSION: The Rasch-modified USE-NM offers a measure of self-efficacy for neuromuscular disorders encountered in a typical specialist clinic. Future considerations could be given to assessing any benefits of multidisciplinary team input, across a specialist neuromuscular service.