Equivalence Testing Research Articles

Validating a Practical Correction for Intravenous Contrast on Computed Tomography–Based Muscle Density

Objective Computed tomography (CT) measured muscle density is prognostic of health outcomes. However, the use of intravenous contrast obscures prognoses by artificially increasing CT muscle density. We previously established a correction to equalize contrast and noncontrast muscle density measurements. While this correction was validated internally, the objective of this study was to obtain external validation using different patient cohorts, muscle regions, and CT series. Methods CT images from 109 patients with kidney tumors who received abdominal CT scans with a multiphase intravenous contrast protocol were analyzed. Paraspinal muscle density measurements taken during noncontrast, venous phase, and delayed phase contrast scans were collected. An a priori correction of −7.5 Hounsfield units (HU) was applied to muscle measurements. Equivalence testing was utilized to determine statistical similarity. Results In the sample of 109 patients (mean age: 63 years [SD: 14.3]; 41.3% female), densities in smaller regions of interest within the paraspinal muscles and the entire paraspinal muscle density (PS) in venous and delayed phase contrast scans were higher than in noncontrast. Equivalence testing showed that average corrected contrast and noncontrast muscle densities were within 3 HU for both muscle measures for the total patient sample, and for a majority of male and female subsamples. The correction is suitable for regions of interests of venous contrast (90% CI: −1.90, −0.69 HU) and delayed contrast scans (90% CI: 0.075, 1.29 HU) and within the PS measures of venous contrast (90% CI: −2.04, −0.94 HU) and delayed contrast scans (90% CI: −0.11, 0.89 HU) Conclusions The previously established correction for contrast of −7.5 HU was applied in a new patient population, axial muscle region, muscle measurement size, and expanded on previously studied contrast phases. The correction produced contrast-corrected muscle densities that were statistically equivalent to noncontrast muscle densities. The simplicity of the correction gives clinicians a tool that seamlessly integrates into practice or research to improve harmonization of data between contrast and noncontrast scans.

Impact of proxymetacaine on the dynamics of cyclopentolate in White 6‐ to 7‐year‐olds

AbstractPurposeThis study compared the efficacy of cyclopentolate hydrochloride at 10‐, 20‐ and 30‐min post‐instillation in White 6‐ to 7‐year‐olds, with and without prior instillation of proxymetacaine hydrochloride. The primary aim was to determine if accurate autorefraction values can be obtained sooner than the current standard of 30‐min post‐cycloplegia. The secondary aim was to investigate whether proxymetacaine hydrochloride enhances the efficiency of cyclopentolate.MethodsParticipants were 112 White 6‐ to 7‐year‐olds from the Child Eye Health Study. The right eye received 0.5% proxymetacaine hydrochloride and 1.0% cyclopentolate hydrochloride, and the left eye received only 1.0% cyclopentolate hydrochloride. Non‐cycloplegic and cycloplegic refractive error (at 0, 10, 20 and 30 min) was measured using a binocular, open‐field autorefractometer. Data were analysed through paired t‐tests, concordance analysis, linear regression, equivalence testing and Bland–Altman analysis, using the 95% limits of agreement.ResultsMean spherical equivalent refraction (SER) (SD) in the right eye at 0‐, 10‐, 20‐ and 30‐min post‐instillation was 0.62 (1.45) D, 1.52 (1.80) D, 1.64 (1.81) D and 1.72 (1.80) D, respectively. Mean left eye SER (SD) were 0.68 (1.24) D, 1.42 (1.66) D, 1.56 (1.66) D and 1.68 (1.72) D, respectively. Bland–Altman analysis showed a high level of agreement, and equivalence testing confirmed that there was no clinically significant difference in SER at 20 and 30 min in both eyes (within ±0.50 D), with mean differences of 0.08 (0.23) D in the right eye and 0.13 (0.30) D in the left eye (p = 0.21). However, SER at 10 and 30 min were equivalent in the right eye only.ConclusionsAccurate autorefraction values can be obtained 20‐min post‐instillation of 1.0% cyclopentolate in white children aged 6–7 years, potentially reducing clinical testing times. Proxymetacaine pre‐instillation allows for reliable measurements as early as 10‐min post‐instillation of cyclopentolate. Further research is needed to validate these findings in non‐White populations and to determine the safe discharge time post‐proxymetacaine instillation.

Pharmaceutical Equivalence of Film-Coated and Chewable Tablets: A Comparative Dissolution Study Using Pulverized Chewable Tablets

Famotidine is a histamine H2 receptor antagonist used in the treatment of gastrointestinal disorders. It is available in multiple formulations, including film-coated tablets, chewable tablets, oral suspension, and injections. The purpose of this study was to develop and evaluate the film-coated tablet (FT) containing famotidine, magnesium hydroxide, and precipitated calcium carbonate, designed to be pharmaceutically equivalent to the marketed chewable tablet (CT). To achieve the pharmaceutical equivalence of two tablets, the dissolution profiles of FT should be similar to those of CT. However, since CT is intended to be chewed before swallowing, testing it in its intact form would not provide accurate results. Therefore, pulverized chewable tablets (PCT) were used as the reference product. The dissolution, performed by the paddle method at 50 rpm, was analyzed by the validated UV method. Similarity factor (f2) and difference factor (f1) were calculated to assess the equivalence of the dissolution profiles. The results demonstrated that the dissolution profiles of the FT and CT were similar. Additionally, the acid-neutralizing capacity test confirmed the equivalence of the two antacids. This study is one of the first to propose that dissolution tests for pharmaceutical equivalence should be conducted on pulverized CTs when developing generic equivalents to CTs.

Comparison of Computational Statistical Packages for the Analysis of Continuous Glucose Monitoring Data with a Reference Software, "Ambulatory Glucose Profile," in Type 1 Diabetes.

Objective: To compare the accuracy of commonly used continuous glucose monitoring (CGM) analysis programs with ambulatory glucose profile (AGP) and Dexcom Clarity (DC) in analyzing CGM metrics in patients with type 1 diabetes (T1D). Research Methods: CGM data up to 90 days from 152 adults using the same CGM and automated insulin delivery system with T1D were collected. Six of the 19 CGM analysis programs (CDGA, cgmanalysis, Glyculator, iglu, EasyGV, and GLU) were selected to compare with AGP and DC. Metrics were compared etween all tools with two one-sided t-tests equivalence testing. For the equivalence test, the acceptable range of deviation was set as ±2 mg/dL for mean glucose, ±2% for time in range (TIR), ±1% for time above range (TAR), time above range level 1 (TAR1), time above range level 2 (TAR2), and coefficient of variation (CV). Results: All packages were compared with each other for all CGM metrics, and most of them had statistically significant differences for at least some metrics. All tools were equivalent to AGP for mean glucose, TIR, TAR, TAR1, and TAR2 within ±2 mg/dL, ±2%, ±1%, ±1% and 1%, respectively. CDGA, Glyculator, cgmanalysis, and iglu were not equivalent to AGP for CV within ±1%. All tools were equivalent to DC for mean glucose, TIR, and TAR2 within ±2 mg/dL, ±2%, and ±1%, respectively. Glyculator was not equivalent for TAR1, TAR, and CV. CGDA, cgmanalysis, and iglu were not equivalent to DC for TAR1 and TAR. EasyGV and GLU were not equivalent for TAR within ±1%. Conclusions: CGM analysis programs reported CGM metrics statistically differently, but these differences may not be applicable in clinical practice. The equivalence test also confirmed that the differences are negligible for TIR and mean glucose, while they can be important for hyperglycemic ranges and CV. A standardization for CGM data handling and analysis is necessary for clinical studies reporting CGM-generated outcomes.

Total and appendicular body composition comparisons between near-infrared reactance spectroscopy and dual energy X-ray absorptiometry.

Near-infrared reactance spectroscopy (NIRS) has become increasingly popular in personal and professional settings now that it has been adapted to provide comprehensive body composition assessments. However, whether NIRS agrees with criterion methods remains unknown. Thus, this study aimed to determine the agreement between NIRS and DXA-derived body composition estimates. Ninety-seven participants completed body composition assessments using DXA, and first-generation (NIRSG1), second-generation (NIRSG2), and muscle-specific NIRS (NIRSFIT) devices. On a separate day, a subset of participants (n = 63) performed maximal voluntary contractions (MVC) on a handgrip dynamometer, which were used in conjunction with total appendicular lean mass (ALM) estimates to provide ratios (MVC/total ALM or MVC/ALM of the arms only) depicting muscle quality index (MQI). Fat mass, fat-free mass, body fat %, and ALM, from NIRSG2, but not bone mineral content (BMC), and NIRSFIT demonstrated equivalence (using equivalence tests) with DXA with R2 from 0.83 to 0.97; though BMC revealed concordance coefficients of 0.83 and an R2 of 0.88. MQI using total ALM from NIRS was not equivalent to DXA, but demonstrated low root mean squared error (0.08 kg/kg) and 95% limits of agreement (±0.21 kg/kg). Indices of visceral adipose tissue (iVAT) from NIRSG1 and NIRSG2 were significantly different (p < 0.001), but were both significantly associated with DXA VAT (NIRSG1 R2: 0.53; NIRSG2 R2: 0.62; both p < 0.001). NIRS appears to demonstrate acceptable agreement with DXA and continual improvements could make NIRS a viable alternative for comprehensive body composition assessments.

Attention and executive delays in early childhood: a meta-analysis of neurodevelopmental conditions.

The objective of this review was to evaluate attention and executive function performance in children with neurodevelopmental conditions across the first 5 years of life, compared to neurotypical peers. MEDLINE, EMBASE, and PsycINFO databases were searched until June 30, 2023, and studies comparing attention or executive function between children with (or at risk for) neurodevelopmental conditions and neurotypical (or low risk) peers, 0 to 5 years old, were included. Of the 4338 studies identified, 111 studies with 12292 participants were included in the meta-analysis. The qualitative analysis of brain development included 5 studies. Primary outcomes were the standardised mean difference (Hedges' g) in attention and executive function between groups. Meta-regressions examined moderating effects of age, biological sex, diagnosis, and measure type. Children with neurodevelopmental conditions showed small delays in attention (n = 49 studies, k = 251 outcomes, g = 0.36, 95% CI 0.23-0.48, p < 0.001) and moderate delays in executive function (n = 64 studies, k = 368 outcomes, g = 0.64,95% CI 0.53-0.76, p < 0.001). Attention and executive function delays could not be identified in the first year (equivalence tests, p < 0.001), small to moderate delays were found in toddlerhood and moderate delays by preschool. Delays identified were largely transdiagnostic, although there was some evidence of diagnosis-specific delays for attention and moderation by measure type (informant rating vs performance-based vs physiological). Qualitative analysis described how delays were underpinned by a divergence of brain development in medial prefrontal regions. These findings highlight the potential of using attention and executive measures to detect delay and to intervene in neurodevelopmental conditions early in life.

Nationwide prevalence and geographic variation of idiopathic intracranial hypertension among women in the United States

The prevalence of idiopathic intracranial hypertension (IIH) is increasing, but this has not been examined on a nationwide scale. Our objective was to determine the nationwide prevalence and geographic distribution of IIH among women in the U.S. Retrospective cross-sectional study using Medicaid claims and electronic health record data from the IRIS® Registry (Intelligent Research in Sight) and Sight Outcomes Research Collaborative (SOURCE). Female Medicaid beneficiaries aged 18-55 with IIH diagnoses and prescriptions for acetazolamide or methazolamide in 2018, excluding those with other causes of intracranial hypertension. We also calculated the proportion of female IIH patients in the U.S. who were insured by Medicaid by combining analyses from the IRIS® Registry and SOURCE. To calculate the total number of IIH patients in the U.S. and by state, we divided the number of Medicaid beneficiaries with IIH by the proportion of IIH patients insured by Medicaid. We then used census data from the 2018 American Community Survey to calculate prevalence. We compared the geographic distribution of IIH to obesity prevalence data from the 2018 Behavioral Risk Factor Surveillance System, using the Moran's I statistic to test for spatial variation. In a validation study, we compared the calculated prevalence of IIH in Minnesota to similar data from the Rochester Epidemiology Project. Of 13,959 female Medicaid beneficiaries with IIH, 6,828 had a prescription for acetazolamide or methazolamide. In the IRIS® Registry and SOURCE, 25% of IIH patients were insured by Medicaid (95 % CI: 16-33%), suggesting that there were 27,312 women aged 18-55 with IIH taking acetazolamide or methazolamide in 2018 (6,828 / 0.25 = 27,312). Prevalence was 3.44 per 10,000 (95% CI: 2.61-5.39), and there was significant geographic variation (Moran's I statistic 0.20, P = 0.03) with higher prevalence in states where obesity was more common. The calculated prevalence of IIH in Minnesota was statistically equivalent to Rochester Epidemiology Project data (P < 0.05 for equivalence test). IIH affects 3.44 per 10,000 women aged 18-55 in the U.S., and there is significant geographic variation, some of which is explained by variation in obesity prevalence.

Feasibility and accuracy of pediatric core temperature measurement using an esophageal probe inserted through the gastric lumen of a second-generation supraglottic airway device: a prospective observational study.

Accurate core temperature measurement in children is crucial; however, measuring esophageal temperature (TE) using a supraglottic airway device (SAD) can be challenging. Second-generation SADs, which have a gastric channel, can measure TE, and reduce gastric air volume. This study aimed to compare TE, measured using a probe inserted through the SAD gastric channel, with tympanic membrane (TTM) and forehead (TZHF) temperatures, measured using a zero-heat-flux cutaneous thermometer, with rectal temperature (TR). Temperature was recorded at 10-min intervals from 10 min after probe insertion until completion of surgery. We performed an equivalence test to evaluate whether the TE, TTM, and TZHF were equivalent to TR, with a margin of 0.3°C. Additionally, intraclass correlation coefficients (ICC) were calculated to assess the reliability of TE and TR at each time point. We included 41 patients in the final analysis. In all patients, the esophageal probe was successfully inserted through the gastric channel of the SAD. When assessing agreement with TR as a reference, TE demonstrated equivalent results at all time points (P < 0.001 at 0, 10, 20, 30, and 40-min intervals and P = 0.018 at the 50-min interval), except at the completion of surgery (P = 0.697). TE also demonstrated good reliability with TR as a reference throughout the surgery (ICC > 0.75). In children with SAD insertion, TE can be accurately and feasibly measured through the SAD's gastric channel, making it suitable for routine application.

Assessing the criterion validity of the activPAL CREA v1.3 algorithm and ActiPASS 2023.12 software for detecting steps during a progressive treadmill-based laboratory protocol

ABSTRACT Thigh-worn accelerometry is commonly implemented to measure step cadence. The default activPAL CREA algorithm is a valid measure of cadence during walking, but its validity during running is unknown. The ActiPASS software is designed to analyse tri-axial accelerometry data from various brands. We tested the validity of CREA v1.3 and ActiPASS 2023.12 to measure step cadence against manually-counted steps. Forty-five participants (26♀, 23.4 ± 4.6 years) completed 5 walking (6 min each, 2–4 mph) and 5 running treadmill (5–7 mph) stages (423 total stages completed). Based on equivalence testing, walking cadence (stages 1–5: 92–124 steps/min) from CREA was statistically equivalent (zone: <±2.2% of the manually-counted mean) to manual counts (92–125 steps/min). However, CREA underpredicted cadence during running stages (stages 6–10: 143–135 steps/min) by ~ 11–20 steps/min (p < 0.001). The ActiPASS-derived cadences were equivalent (zone: <±3.3%) to manual counts for all walking stages (99–127 steps/min) except Stage 1 (zone: ±10.5%). ActiPASS underpredicted cadences during running (stages 6–10: 137–153 steps/min) by ~ 10–16 steps/min (p < 0.001) compared to manual counts (stages 6–10: 154–164 steps/min). The CREA v1.3 algorithm is a valid measure of cadence during walking while ActiPASS 2023.12 is a valid measure of cadence during medium-fast walking. Further research is required to improve step cadence estimation across ambulation speeds.

Convergent Validity of Garmin Vivofit Jr. 3 and Fitbit Ace 3 for Monitoring Daily Physical Activity of Children

ABSTRACT This study aimed to assess the agreement in physical activity (PA) estimates from Garmin Vivofit Jr. 3 (VFJ 3) and Fitbit Ace 3 (Ace 3) with a research-grade accelerometer (wGT3X-BT) in children under free-living conditions. Twenty-five children (Girls: 56%, Age: 10.1 ± 2.5 years, BMI: 17.1 ± 2.4 kg/m2) performed daily activities for 7 consecutive days while wearing VFJ 3, Ace 3, and wGT3X-BT. Pearson correlations, Bland–Altman plots, mean percent error (MPE), mean absolute percent error (MAPE), and equivalence tests were conducted to evaluate the agreement of VFJ 3 and Ace 3 with wGT3X-BT. VFJ 3 and Ace 3 had strong positive correlations (range: r = 0.71 to 0.95) with wGT3X-BT in estimating steps and moderate-to-vigorous PA (MVPA) and provided relatively valid estimates for daily steps. Although Ace 3 had no systematic bias and a low group measurement error (MPE: −10.1%) in estimating MVPA, VFJ 3 consistently overestimated daily MVPA. Collectively, VFJ 3 and Ace 3 can be valid devices to monitor children’s PA levels with daily step counts.

Proactive control for conflict resolution is intact in subclinical obsessive-compulsive individuals.

BackgroundObsessive-compulsive (OC) traits (i.e., tendency to implement stereotyped behaviors to avoid negative consequences) are transversally observed in psychiatric disorders largely differing in terms of clinical manifestations and etiopathogenesis. Interestingly, OC traits were also extensively found in the prodromal phases of the full-blown psychopathology and in healthy relatives of affected individuals. Moreover, OC traits were found to be associated—and possibly underlain by—cognitive control impairments. Nonetheless, the role of such interplay in the onset of OC disorders is yet to be understood. We hypothesized that OC traits are associated with abnormalities in proactively implement cognitive control for solving conflict.MethodsWe administered healthy individuals (n = 104) with the perifoveal spatial Stroop task to measure their ability of solving conflict in a proactive fashion, and with Obsessive-Compulsive Inventory (OCI) to stratify population according to the severity of OC traits.ResultsAnalysis of response times by means of Linear Mixed-effect models revealed that proactive control performance was not associated with and the severity of OC traits. Furthermore, an equivalence test (Two One-Sided Test) revealed that the association between OCI scores and task performance was equivalent to zero.ConclusionThese results suggest that the interplay between OC traits and proactive control abnormalities might not contribute to the development of OC-related disorders. Therefore, the role of other cognitive endophenotypes should be scrutinized for exploiting alternative prevention and intervention strategies.

Development of an accelerometer-based wearable sensor approach for alcohol consumption detection.

Alcohol is a commonly used substance associated with significant public health consequences. Treatment is often stigmatized and limited with regard to both access and affordability, demonstrating the need for innovations in alcohol treatment. Accelerometer sensors can detect drinking without user input and are widely incorporated into wearable devices, increasing accessibility and affordability. We compared a distributional and random forest classification approach to detect and evaluate sensor-based drinking data. Data were collected at a local state fair (n = 194), where participants drank water at specified intervals interspersed with confounding behaviors (e.g., touching nose, rubbing forehead, or yawning) while wearing an Android-based smartwatch for 10 min. Participants were randomized to receive one of three drinking container shapes: pint, martini, or wine. The random forest model achieved an overall testing accuracy of 93% (sensitivity = 0.32; specificity = 0.99; positive predictive value = 0.74). The distributional algorithm achieved an overall accuracy of 95% (sensitivity = 0.76; specificity = 0.97; positive predictive value = 0.72). The distributional algorithm had a significantly greater accuracy (t(193) = 7.73, p < 0.001, d = 0.56) and sensitivity (t(193) = 24.5, p < 0.001, d = 1.76). Equivalency testing demonstrated significant equivalency to the ground truth for sip duration (tlower(193) = 16.92, p < 0.001; tupper(193) = -9.85, p < 0.001) and between-sip interval (tlower(193) = 1.72, p = 0.044; thigher(193) = -3.96, p < 0.001). However, the random forest did not have significant equivalency to the ground truth for between-sip interval (tlower(193) = 1.98, p = 0.025; thigher(193) = 0.160, p = 0.564). Overall, the results indicated that consumer-grade smartwatches can be utilized to detect and measure alcohol use behavior using machine learning and distributional algorithms. This work provides the methodological foundation for future research to analyze the behavioral pharmacology of alcohol use and develop accessible just-in-time clinical interventions.

Favourable dentoalveolar changes after lower premolar extractions for Class III camouflage with completely customized lingual appliances

BackgroundThe aim of the investigation was to evaluate if the inclination of the lower anterior teeth can be controlled reliably after lower premolar extraction for Class III camouflage treatment with completely customized lingual appliances (CCLAs). Treatment outcome was tested against the null hypothesis that lower premolar extractions for non-surgical camouflage treatment of a Class III malocclusion will lead to further compensation by retroclining mandibular incisors during CCLA treatment.MethodsThis retrospective study included 25 patients (f/m 12/13; mean age 20.7 years, SD 9.5 years) with uni- or bilateral Class III molar relationship and a Wits value of ≤ -2 mm. In all consecutively debonded patients, lower premolars were extracted to correct the sagittal relationship with a non-surgical camouflage approach. Lateral head films prior to (T1) and at the end of lingual orthodontic treatment (T2) were used to evaluate skeletal and dentoalveolar effects. A paired t-test with alpha = 5% was used to define differences between the endpoints. The linear correlation between the inclination of the mandibular incisors at T1 and the achieved correction was measured with the Pearson correlation coefficient (PCC). A Schuirmann’s TOST equivalence test was used to check if the final lower incisor inclination was within the defined norms.ResultsThe null hypothesis was rejected as the mean lower incisor inclination was improved by 1.8° despite lower premolar extractions (T1: 86.8°/ T2: 88.6°). There was a strong correlation (-0.75) between the lower incisor inclination at T1 and the achieved correction indicating a controlled correction towards the norm regardless of the initial incisor position. At T2, the interincisal angle as well as the lower incisor inclination were within the norm.ConclusionLower premolar extractions for non-surgical camouflage treatment of a Class III malocclusion will not lead to undesired retroclining of mandibular incisors during CCLA treatment even in severe cases.

Equivalence Tests Before the End of Follow-up Under Box–Cox Transformation Model

Equivalence Tests Before the End of Follow-up Under Box–Cox Transformation Model

Computational Study Protocol: Leveraging Synthetic Data to Validate a Benchmark Study for Differential Abundance Tests for 16S Microbiome Sequencing Data

Background The utility of synthetic data in benchmark studies depends on its ability to closely mimic real-world conditions and to reproduce results obtained from experimental data. Here, we evaluate the performance of differential abundance tests for 16S metagenomic data. Building on the benchmark study by Nearing et al. (1), who assessed 14 differential abundance tests using 38 experimental datasets in a case-control design, we validate their findings by generating synthetic datasets that mimics the experimental data. We will employ statistical tests to rigorously assess the similarity between synthetic and experimental data and to validate the conclusions on the performance of these tests drawn by Nearing et al. (1). This protocol adheres to the SPIRIT guidelines and is, to our knowledge, the first of its kind in computational benchmark studies. Methods We replicate Nearing et al.’s (1) methodology, incorporating synthetic data simulated using two distinct tools, mirroring each of the 38 experimental datasets. Equivalence tests will be conducted on 43 data characteristics comparing synthetic and experimental data, complemented by principal component analysis for overall similarity assessment. The 14 differential abundance tests will be applied to both synthetic and experimental datasets, evaluating the consistency of significant feature identification and the number of significant features per tool. Correlation analysis and multiple regression will explore how differences between synthetic and experimental data characteristics may affect the results. Conclusions Synthetic data enables the validation of findings through controlled experiments. We assess how well synthetic data replicates experimental data, validate previous findings and delineate the strengths and limitations of synthetic data in benchmark studies. Moreover, to our knowledge this is the first computational benchmark study to systematically incorporate synthetic data for validating differential abundance methods while strictly adhering to a pre-specified study protocol following SPIRIT guidelines, contributing significantly to transparency, reproducibility, and unbiased research.

On the Equivalence Test and Sample Size Procedures for Simple Linear Regressions with Applications to ANCOVA and Moderation Analysis

On the Equivalence Test and Sample Size Procedures for Simple Linear Regressions with Applications to ANCOVA and Moderation Analysis

Smartphone three-dimensional imaging for body composition assessment using non-rigid avatar reconstruction.

Modern digital anthropometry applications utilize smartphone cameras to rapidly construct three-dimensional humanoid avatars, quantify relevant anthropometric variables, and estimate body composition. In the present study, 131 participants ([73 M, 58 F] age 33.7 ± 16.0 y; BMI 27.3 ± 5.9 kg/m2, body fat 29.9 ± 9.9%) had their body composition assessed using dual-energy X-ray absorptiometry (DXA) and a smartphone 3D scanning application using non-rigid avatar reconstruction. The performance of two new body fat % estimation equations was evaluated through reliability and validity statistics, Bland-Altman analysis, and equivalence testing. In the reliability analysis, the technical error of the measurement and intraclass correlation coefficient were 0.5-0.7% and 0.996-0.997, respectively. Both estimation equations demonstrated statistical equivalence with DXA based on ±2% equivalence regions and strong linear relationships (Pearson's r 0.90; concordance correlation coefficient 0.89-0.90). Across equations, mean absolute error and standard error of the estimate values were ~ 3.5% and ~ 4.2%, respectively. No proportional bias was observed. While continual advances are likely, smartphone-based 3D scanning may now be suitable for implementation for rapid and accessible body measurement in a variety of applications.

A-346 Evaluating 14-3-3η Detection in Finger Prick Blood Using Lateral Flow Technology: Advancing Clinical Laboratory Diagnostics

Abstract Background The protein 14-3-3η is a critical biomarker in the diagnosis and monitoring of autoimmune rheumatologic disorders, and its early detection is pivotal for patient outcomes. Previous research has established the significance of 14-3-3η as a biomarker, particularly in inflammatory polyarthritis, as well as patients’ and physicians’ interest in near-patient testing. While 14-3-3η is traditionally measured in serum via ELISA, this study explores the innovative use of lateral flow technology (LFT) for its detection in finger prick blood, addressing the urgent need for near-patient testing.This research aims to evaluate the technical and clinical performance of 14-3-3η measurement using LFT in comparison to standard ELISA methods, with an emphasis on its detectability in finger prick blood. Methods This study included two phases of testing involving patient serum and spiked whole blood. In the serum phase, 53 samples (19 NEG, ≤0.19 ng/mL, and 34 POS, 0.27 to 28 ng/mL 14-3-3η) were tested using LFT. LFT results were compared to JOINTstat® ELISA measurements for concordance. For whole blood, recombinant 14-3-3η and ELISA-positive serum samples were spiked into whole blood at increasing concentrations (0.4 to 3.2 ng/mL) and tested with LFT. Concordance criteria included visual inspection of test and control lines, with results captured and analyzed using a reference key card. The study was extended to assess 14-3-3η levels in consented patients with 22 matched finger prick and venous serum samples​​. Results In serum testing, LFT demonstrated 100% positivity in detecting 14-3-3η for POS samples. Among NEG samples, 85% tested negative, with 15% positive, indicating a strong concordance between LFT and ELISA. The LFT's ability to semi-quantitatively measure 14-3-3η was confirmed by a significant Kruskal-Wallis test (p&amp;lt;0.0001) across four intensity groups. In whole blood testing, LFT correctly identified all samples spiked at concentrations ≥0.5 ng/mL. The Spearman correlation showed a strong and significant association (r=0.96 to 0.98, p=0.001) between LFT test line intensity and spiked 14-3-3η levels. Finally, the equivalence testing for finger prick and venous serum samples affirmed the LFT’s reliability, with a strong correlation (p&amp;lt;0.0001), underscoring its potential for near-patient testing​​. Conclusions The study validates LFT as a reliable and semi-quantitative method for detecting 14-3-3η in finger prick blood, demonstrating strong concordance with traditional ELISA measurements. The findings support the feasibility of LFT in near-patient testing for early detection, prognosis, and monitoring of autoimmune diseases, paving the way for enhanced patient accessibility. Future research will focus on integrating this technology into routine clinical care and examining its impact on patient management and outcomes.

The Validity of Apple Watch Series 9 and Ultra 2 for Serial Measurements of Heart Rate Variability and Resting Heart Rate.

The widespread use of wearable devices has enabled continuous monitoring of biometric data, including heart rate variability (HRV) and resting heart rate (RHR). However, the validity of these measurements, particularly from consumer devices like Apple Watch, remains underexplored. This study aimed to validate HRV measurements obtained from Apple Watch Series 9 and Ultra 2 against the Polar H10 chest strap paired with the Kubios HRV software, which together served as the reference standard. A prospective cohort of 39 healthy adults provided 316 HRV measurements over a 14-day period. Generalized Estimating Equations were used to assess the difference in HRV between devices, accounting for repeated measures. Apple Watch tended to underestimate HRV by an average of 8.31 ms compared to the Polar H10 (p = 0.025), with a mean absolute percentage error (MAPE) of 28.88% and a mean absolute error (MAE) of 20.46 ms. The study found no significant impact of RHR discrepancies on HRV differences (p = 0.156), with RHR showing a mean difference of -0.08 bpm, an MAPE of 5.91%, and an MAE of 3.73 bpm. Equivalence testing indicated that the HRV measurements from Apple Watch did not fall within the pre-specified equivalence margin of ±10 ms. Despite accurate RHR measurements, these findings underscore the need for improved HRV algorithms in consumer wearables and caution in interpreting HRV data for clinical or performance monitoring.

Relationship between reasoning, autistic and alexithymic traits in moral judgments

The present research investigated whether individuals with Autism Spectrum Disorder (ASD) present with specificities of moral reasoning. Some previous exploratory studies have assessed the differences in moral judgment between ASD and control participants, but results were mixed. The present study aimed to quantify such differences using a larger sample and a standard moral task built upon the new CNI (Consequences, Norms and Generalized Inaction) model of moral judgment that resolves multiple confounds in the measurement of moral judgments. A total of 148 adults with ASD and 151 controls completed 24 sacrificial dilemmas from the CNI battery, the Toronto Alexithymia Scale and the Cognitive Reflection Task. We did not find any differences in moral judgments between ASD and control participants, and this pattern was consistent for all the CNI parameters. Equivalence tests revealed that it can be safely excluded that our study missed medium to large differences in moral judgments between ASD and control participants when assessed using sacrificial dilemmas. Additional data quality checks allow to rule out the possibility that the small differences in moral judgments between the groups are due to poor data quality. The implications of these findings and directions for future research are discussed.