Cumulative Estimates Research Articles

Dealing with regression models’ endogeneity by means of an adjusted estimator for the Gaussian copula approach

AbstractEndogeneity in regression models is a key marketing research concern. The Gaussian copula approach offers an instrumental variable (IV)-free technique to mitigate endogeneity bias in regression models. Previous research revealed substantial finite sample bias when applying this method to regression models with an intercept. This is particularly problematic as models in marketing studies almost always require an intercept. To resolve this limitation, our research determines the bias’s sources, making several methodological advances in the process. First, we show that the cumulative distribution function estimation’s quality strongly affects the Gaussian copula approach’s performance. Second, we use this insight to develop an adjusted estimator that improves the Gaussian copula approach’s finite sample performance in regression models with (and without) an intercept. Third, as a broader contribution, we extend the framework for copula estimation to models with multiple endogenous variables on continuous scales and exogenous variables on discrete and continuous scales, and non-linearities such as interaction terms. Fourth, simulation studies confirm that the new adjusted estimator outperforms the established ones. Further simulations also underscore that our extended framework allows researchers to validly deal with multiple endogenous and exogenous regressors, and the interactions between them. Fifth, we demonstrate the adjusted estimator and the general framework’s systematic application, using an empirical marketing example with real-world data. These contributions enable researchers in marketing and other disciplines to effectively address endogeneity problems in their models by using the improved Gaussian copula approach.

Deep Learning for Opportunistic Rain Estimation via Satellite Microwave Links

Accurate precipitation measurement is critical for managing flood and drought risks. Traditional meteorological tools, such as rain gauges and remote sensors, have limitations in resolution, coverage, and cost-effectiveness. Recently, the opportunistic use of microwave communication signals has been explored to improve precipitation estimation. While there is growing interest in using satellite-to-earth microwave link (SMLs) for machine learning-based precipitation estimation, direct rainfall estimation from raw signal-to-noise ratio (SNR) data via deep learning remains underexplored. This study investigates a range of machine learning (ML) approaches, including deep learning (DL) models and traditional methods like gradient boosting machine (GBM), for estimating rainfall rates from SNR data collected by interactive satellite receivers. We develop real-time models for rainfall detection and estimation using downlink SNR signals from satellites to user terminals. By leveraging a year-long dataset from multiple locations—including SNR measurements paired with disdrometer and rain-gauge data—we explore and evaluate various ML models. Our final models include ensemble approaches for both rainfall detection and cumulative rainfall estimation. The proposed models provide a reliable solution for estimating precipitation using Earth–satellite microwave links, potentially improving precipitation monitoring. Compared to the state-of-the-art power-law-based models applied to similar datasets reported in the literature, our ML models achieve a 46% reduction in the RMSE

Evaluating the connection between mean platelet volume (MPV) and peripheral arterial disease risk: a meta-analysis

Background: Numerous studies have been conducted to evaluate the role of Mean Platelet Volume (MPV) in relation to Peripheral Artery Disease (PAD). However, the results of these studies have been inconsistent regarding the significance of MPV as an indicator for PAD. Objective: This meta-analysis aimed to clarify the role of MPV in PAD by collecting and analyzing data from various studies. The goal was to provide a more definitive assessment of whether MPV levels could serve as a reliable indicator for PAD Methods: We conducted a meta-analysis from July to August 2024, utilizing data from three major databases: Scopus, Embase, and PubMed. We gathered data on MPV levels from studies comparing PAD patients with control groups. The meta-analysis included cumulative effect estimates, with analysis performed using the inverse variance method to synthesize data and evaluate the overall effect of MPV on PAD. Results: Nine studies were included in this meta-analysis, comprising 1,214 PAD cases and 6,568 controls. Our analysis demonstrated that MPV was a significant marker in PAD, with PAD patients having higher MPV levels compared to controls (MD: 0.46; 95%CI: 0.25, 0.66; p Egger: 0.0911; p Heterogeneity <0.0001; p <0.0001). Conclusion: Our findings support that MPV is an important indicator in the context of PAD. Further study is needed to explore the clinical applications of MPV in PAD and to establish standardized thresholds for its use in clinical practice. Keyword: diagnosis, mean platelet volume, peripheral disease, predictor

Outcomes of atrial fibrillation ablation in community hospitals with and without onsite cardiothoracic surgery availability.

Limited data exist on outcomes of atrial fibrillation (AF) catheter ablation based on hospital setting and, specifically, the availability of onsite cardiothoracic surgery (CTS). We aimed to describe the characteristics and outcomes of catheter ablation for AF performed at a facility with and without CTS. This was a retrospective study of consecutive patients who underwent catheter ablation for AF at hospital with (CTS) and without cardiothoracic surgery (N-CTS) from January 2011 through December 2019. Clinical and procedural characteristics, complications, and 1-year outcomes, including clinical events and AF recurrence, were collected. There were 326 unique patients who underwent an index AF ablation procedure: 206 CTS patients and 120 N-CTS patients. There were no differences inoverall cardiac complications (2.5% vs. 5.8%), including mapping catheter entrapment requiring open-heart surgery (0% vs. 0.5%), pericardial effusion requiring pericardiocentesis (0.8% vs. 0.5%), hemopericardium (1.7% vs. 0.5%), acute myocardial infarction (0% vs. 1.0%), and sinus node injury (0% versus 0.5%) (all P values > .05)between N-CTS and CTS patients. Likewise, overall noncardiac complications (20.7% vs. 19.8%, P = .85), including bleeding, cerebrovascular accident, and phrenic or vagus nerve injury, were similar between N-CTS and CTS hospitals. Also, 1-year cumulative Kaplan-Meier estimates of overall AF recurrence (11.6% vs. 16.4%; log-rank P = 0.21; HR 1.47; 95% CI, 0.79-2.74) were not statistically significant between N-CTS and CTS hospitals. Catheter ablation procedure is safe and effective regardless of onsite CTS presence, and there were no significant differences between the two hospital settings.

Relationship between cumulative silica exposure and silicosis: a systematic review and dose-response meta-analysis

BackgroundSilicosis, a chronic respiratory disease caused by crystalline silica exposure, is a persistent global lung health issue. No systematic review of the relationship between cumulative respirable crystalline silica (RCS) exposure...

Short-term primary and revision modular dual-mobility cup total hip arthroplasty outcomes in high-risk dislocation patients: a retrospective study

PurposeModular dual-mobility cups (MDMCs) have a lower risk for dislocation after total hip arthroplasty (THA). The primary aims of our study were to analyze implant survivorship and to determine complications, especially dislocation, and revision rates of primary THAs used for hip fracture patients and for revision THAs. Secondary aims were to evaluate mortality after MDMC surgery and to find out if introduction of MDMC at our institution (Kuopio University Hospital, Finland) have decreased dislocation rate.MethodsThis retrospective cohort study consisted of 101 MDMC patients who were consecutively operated at our institution between April 1, 2018 and June 30, 2020. The implant survival rate, complications and mortality were evaluated with minimum of 2-year follow-up. Finnish Hospital Discharge Register was used to find out yearly dislocation rates following THA at our institution.ResultsThe cumulative estimate implant survival after MDMC in the primary THA group was 97% at 2 years, and in the revision THA group, it was 90% at 2 years. Dislocation was a rare complication in the primary THA group (1.4%), while it was common in revision THA group (12.9%). The cumulative estimate for mortality after MDMC in the primary THA group was 13% at 2 years, and in the revision group, it was also 13% at 2 years. The yearly number of patients who had re-hospitalization period due to THA dislocation decreased 46% after implementation of MDMC.ConclusionShort-term survival and complication rates after MDMC were excellent after primary THA and moderate after revision THA. Implementation of MDMC THA for hip fracture patients seems to have effectively decrease dislocation rate during a short follow-up.

Occupational exposure to benzene and risk of non-Hodgkin lymphoma in an extended follow-up of two population-based prospective cohorts of Chinese men and women.

The carcinogenicity of benzene was reevaluated by the International Agency for Research on Cancer in 2017, with the Working Group reaffirming positive yet inconclusive associations with non-Hodgkin lymphoma (NHL). To extend our previous observation of a significant exposure-response for cumulative occupational benzene exposure and NHL risk among Chinese women in a population-based cohort in Shanghai, we extended follow-up of this cohort and pooled the data with a similarly designed population-based cohort of men in Shanghai. Cumulative exposure estimates were derived for 134,449 participants in the pooled analysis by combining ordinal job-exposure matrix intensity ratings with quantitative benzene measurements from an inspection database of Shanghai factories. Associations between benzene exposure metrics and NHL (n = 363 cases including multiple myeloma [MM]) were assessed using Cox proportional hazard models. Ever occupational exposure to benzene in the pooled population was associated with NHL risk (HR = 1.5, 95% CI = 1.2-2.0), and exposure-response relationships were observed for increasing duration (ptrend = .003) and cumulative exposure (ptrend = .003). Associations with ever exposure, duration, and cumulative exposure were similar for NHL with and without MM in the case definition, including lifetime cumulative exposures in the highest quartile (HR = 1.6, 95% CI = 1.1-2.4 with MM included; HR = 1.7, 95% CI = 1.1-2.7 with MM excluded). An elevated risk of the chronic lymphocytic leukemia subtype was suggested in the pooled analyses (HR for ever vs. never exposure = 2.3, 95% CI = 0.9-5.6). These observations provide additional support for a plausible association between occupational benzene exposure and risk of NHL.

Evidence-based radiology 5years on-a single-centre review of image referral appropriateness.

The iRefer guidelines provide evidence-based recommendations on imaging and are designed to facilitate appropriate referrals and limit unnecessary radiation exposure. In 2017, a review at this institution assessed the appropriateness of imaging referrals. This study provides an update 5years later on the referral appropriateness and aims to assess what impact the previous review has had on referral appropriateness. A retrospective study of 945 referrals across GPs, ED, and inpatients was audited against the iRefer guidelines with costs and cumulative dose estimates calculated for inappropriate referrals considering salaries of those involved, the average time spent performing and reporting radiographs, and the median effective dose values. Results show a decrease in the volume of requests overall with the relative proportion of inappropriate requests rising significantly. Inappropriate requests for abdominal X-rays from GPs decreased from 72 to 37.5%, whereas inappropriate ED referrals increased from 38 to 46% and inappropriate inpatient requests remained static at 30%. The proportion of inappropriate GP requests for spinal radiographs significantly increased for cervical, thoracic, and lumbar spine radiographs, respectively (18 to 66%; 47 to 72%; 53 to 80%; p-value < 0.001). Inappropriate radiographs represent an increased financial and dose-based burden. The volume of radiograph requests reduced after over a 5-year interval; however, the relative proportion of inappropriate requests rose significantly. The iRefer guidelines provide a useful resource to ensure that imaging is used appropriately, effectively, and safely; however, more work is needed to ensure that requests are adhering to these guidelines.

Assessment of regulatory ecosystem services of green plants in urban ecosystems

The article presents the results of research on the assessment of ecosystem services of green tree stands on the territory of the first academic campus of the National University of Kyiv-Mohyla Academy using the MyTree tool. It is a part of the i-Tree tool set developed by the Forest Service of the United States Department of Agriculture (USDA) of the comprehensive program, designed to assess the ecosystem services provided by individual trees or small groups of trees. Research has established that the most important regulatory services were carbon dioxide absorption, microclimate regulation, energy saving, air purification from ozone and sulfur dioxide. Calculations by the MyTree tool show the annual cost of tree planting services on campus and its projected cumulative growth after 20 years. According to the calculations of the MyTree tool, this year’s cost of tree plantation services of the first academic campus of the National University of Kyiv-Mohyla Academy was $847.29, and according to forecasts, after 20 years it will cumulatively increase to $18,895.36. Estimates of the cost of individual components of regulatory ecosystem services are provided. The cumulative estimate over the next 20 years for CO2 sequestration was $4,129.15, which includes the sequestration of 21,963.55 kg of carbon. Air purification for 20 years is estimated at $1,342.66, which includes absorption and neutralization of 656.24 kg of O3, 117.47 kg of SO2, 54.45 kg of NO2, and 34.26 kg of solid dust particles PM2.5. Energy savings are estimated at $10,791.14, which includes energy savings of 100,448.21 kW. The tree species Aesculus hippocastanum (Bitter chestnut), Picea abies (European spruce), Picea pungens (Blue spruce), Betula pendula (Hanging birch) and Ulmus laevis (Smooth elm) provide the highest value of services. The results of this study can be used in the future to improve the planning and management of green areas of the university campus, taking into account the value of their ecosystem services.In general, the study confirmed the importance of monitoring and evaluating the ecosystem services of green spaces in urban ecosystems for making sustainable decisions regarding the development of urban areas, supporting the well-being and health of the population.

Ultrasound normalized cumulative residual entropy imaging: Theory, methodology, and application

Background and Objective:Ultrasound information entropy imaging is an emerging quantitative ultrasound technique for characterizing local tissue scatterer concentrations and arrangements. However, the commonly used ultrasound Shannon entropy imaging based on histogram-derived discrete probability estimation suffers from the drawbacks of histogram settings dependence and unknown estimator performance. In this paper, we introduced the information-theoretic cumulative residual entropy (CRE) defined in a continuous distribution of cumulative distribution functions as a new entropy measure of ultrasound backscatter envelope uncertainty or complexity, and proposed ultrasound CRE imaging for tissue characterization. Methods:We theoretically analyzed the CRE for Rayleigh and Nakagami distributions and proposed a normalized CRE for characterizing scatterer distribution patterns. We proposed a method based on an empirical cumulative distribution function estimator and a trapezoidal numerical integration for estimating the normalized CRE from ultrasound backscatter envelope signals. We presented an ultrasound normalized CRE imaging scheme based on the normalized CRE estimator and the parallel computation technique. We also conducted theoretical analysis of the differential entropy which is an extension of the Shannon entropy to a continuous distribution, and introduced a method for ultrasound differential entropy estimation and imaging. Monte-Carlo simulation experiments were performed to evaluate the estimation accuracy of the normalized CRE and differential entropy estimators. Phantom simulation and clinical experiments were conducted to evaluate the performance of the proposed normalized CRE imaging in characterizing scatterer concentrations and hepatic steatosis (n = 204), respectively. Results:The theoretical normalized CRE for the Rayleigh distribution was π/4, corresponding to the case where there were ≥10 randomly distributed scatterers within the resolution cell of an ultrasound transducer. The theoretical normalized CRE for the Nakagami distribution decreased as the Nakagami parameter m increased, corresponding to that the ultrasound backscattered statistics varied from pre-Rayleigh to Rayleigh and to post-Rayleigh distributions. Monte-Carlo simulation experiments showed that the proposed normalized CRE and differential entropy estimators can produce a satisfying estimation accuracy even when the size of the test samples is small. Phantom simulation experiments showed that the proposed normalized CRE and differential entropy imaging can characterize scatterer concentrations. Clinical experiments showed that the proposed ultrasound normalized CRE imaging is capable to quantitatively characterize hepatic steatosis, outperforming ultrasound differential entropy imaging and being comparable to ultrasound Shannon entropy and Nakagami imaging. Conclusion:This study sheds light on the theory and methodology of ultrasound normalized CRE. The proposed ultrasound normalized CRE can serve as a new, flexible quantitative ultrasound envelope statistics parameter. The proposed ultrasound normalized CRE imaging may find applications in quantified characterization of biological tissues. Our code will be made available publicly at https://github.com/zhouzhuhuang.

Serum calcium and mortality in pediatric pneumonia patients admitted to the PICU: a retrospective cohort study

This study investigates serum calcium’s prognostic value in pediatric pneumonia, focusing on its correlation with PICU mortality, to enhance understanding and treatment approaches in this field. Data from 414 pediatric pneumonia patients (2010–2019) admitted to the intensive care units at the Children’s Hospital, Zhejiang University School of Medicine were analyzed. The study utilized restricted cubic spline analysis, Cox proportional hazard regression, and Kaplan–Meier survival curve analysis to assess the relationship between serum calcium levels at admission and PICU mortality risk. After adjusting for multivariate factors, for each 1 mmol/dL increase in serum calcium, the risk of mortality decreased by 24% (HR: 0.76, 95% CI 0.67–0.87). Among the three levels of serum calcium groups, higher serum calcium levels were linked to a 63% reduction in the mortality rate compared to lower levels (HR: 0.37, 95% CI 0.16–0.84). The cumulative hazard estimates of mortality significantly differed across serum calcium groups (log-rank P = 0.032). This association was consistent across diverse subgroups (P for interaction > 0.05). Higher serum calcium levels are associated with decreased PICU mortality in pediatric pneumonia, highlighting its potential as a prognostic marker.

Invited Commentary: Influence of Incomplete Death Information on Cumulative Risk Estimates.

Censoring at death is the only feasible option if death is not recorded and individuals who died simply no longer contribute visits, such as in the setting of Barberio et al (Am J Epidemiol. 2024) before they acquired access to mortality information. Censoring at death is known to lead to biased estimates of the probability of the event of interest before time $t$. Barberio et al show through simulations that this bias increases with increasing mortality. However, when analyzing claims data it is often important to not exclude individuals with shorter life expectancies: an important strength of observational studies is that they allow estimating treatment effects in more varied populations than typically included in randomized clinical trials. We derive an analytic expression for the bias, and provide two upper bounds for the bias. The bounds inform the usefulness of obtaining mortality information. If the probability of death before the event is known to be small, wider confidence intervals can be created using the first bound on the bias; we provide an algorithm. If the bias is large, obtaining mortality information is important. Barberio et al show that obtaining mortality information can be essential in practice.

Impact of Ambient Temperature on Mortality Burden and Spatial Heterogeneity in 16 Prefecture-Level Cities of a Low-Latitude Plateau Area in Yunnan Province: Time-Series Study.

The relation between climate change and human health has become one of the major worldwide public health issues. However, the evidence for low-latitude plateau regions is limited, where the climate is unique and diverse with a complex geography and topography. This study aimed to evaluate the effect of ambient temperature on the mortality burden of nonaccidental deaths in Yunnan Province and to further explore its spatial heterogeneity among different regions. We collected mortality and meteorological data from all 129 counties in Yunnan Province from 2014 to 2020, and 16 prefecture-level cities were analyzed as units. A distributed lagged nonlinear model was used to estimate the effect of temperature exposure on years of life lost (YLL) for nonaccidental deaths in each prefecture-level city. The attributable fraction of YLL due to ambient temperature was calculated. A multivariate meta-analysis was used to obtain an overall aggregated estimate of effects, and spatial heterogeneity among 16 prefecture-level cities was evaluated by adjusting the city-specific geographical characteristics, demographic characteristics, economic factors, and health resources factors. The temperature-YLL association was nonlinear and followed slide-shaped curves in all regions. The cumulative cold and heat effect estimates along lag 0-21 days on YLL for nonaccidental deaths were 403.16 (95% empirical confidence interval [eCI] 148.14-615.18) and 247.83 (95% eCI 45.73-418.85), respectively. The attributable fraction for nonaccidental mortality due to daily mean temperature was 7.45% (95% eCI 3.73%-10.38%). Cold temperature was responsible for most of the mortality burden (4.61%, 95% eCI 1.70-7.04), whereas the burden due to heat was 2.84% (95% eCI 0.58-4.83). The vulnerable subpopulations include male individuals, people aged <75 years, people with education below junior college level, farmers, nonmarried individuals, and ethnic minorities. In the cause-specific subgroup analysis, the total attributable fraction (%) for mean temperature was 13.97% (95% eCI 6.70-14.02) for heart disease, 11.12% (95% eCI 2.52-16.82) for respiratory disease, 10.85% (95% eCI 6.70-14.02) for cardiovascular disease, and 10.13% (95% eCI 6.03-13.18) for stroke. The attributable risk of cold effect for cardiovascular disease was higher than that for respiratory disease cause of death (9.71% vs 4.54%). Furthermore, we found 48.2% heterogeneity in the effect of mean temperature on YLL after considering the inherent characteristics of the 16 prefecture-level cities, with urbanization rate accounting for the highest proportion of heterogeneity (15.7%) among urban characteristics. This study suggests that the cold effect dominated the total effect of temperature on mortality burden in Yunnan Province, and its effect was heterogeneous among different regions, which provides a basis for spatial planning and health policy formulation for disease prevention.

Seabird bycatch in European waters

AbstractThe incidental capture (bycatch) of seabirds is a global conservation issue and a top threat to European species that demands urgent conservation and management action. Here, we present the first European review of seabird bycatch data, considering all fishing gears and data collection methods available in the region. We calculate seabird bycatch numbers per species, family, country and European marine region and assess the reliability of the data available. The cumulative bycatch estimate extracted from this review suggests that about 195,000 seabirds (ranging from around 130,000 to 380,000) are bycaught in European waters annually. The most affected seabird species is the Common Guillemot Uria aalge with over 31,000 birds killed per year. The marine region with the highest bycatch estimate is the Northeast Atlantic (over 115,000 seabirds year−1). Gillnet fisheries are responsible for the highest bycatch levels, with over 95,000 seabirds year−1, followed by longline fisheries. The families most affected by bycatch are Anatidae and Alcidae. These numbers are likely an underestimation since we were unable to find bycatch estimates, or to extrapolate estimates from available bycatch data for 12 (out of 34) European coastal states. Our assessment also identified significant data gaps in key areas such as Gran Sol (in the north‐east Atlantic), the central and Eastern Mediterranean and the Black Sea. Combining systematic data collection with immediate implementation of mitigation measures will be crucial to fill in knowledge gaps, reduce current mortality levels and meet international conservation commitments such as those of the European Union and the Convention on Migratory Species.

Age at natural menopause and its associated characteristics among Brazilian women: cross-sectional results from ELSI-Brazil.

This study aimed to determine the median age at natural menopause and analyze lifestyle, anthropometric, and dietary characteristics associated with the age at natural menopause among Brazilian women. This cross-sectional study involved 2,731 women 50 years and over, drawn from the baseline of the Brazilian Longitudinal Study of Aging (ELSI-Brazil, 2015/16). Nonparametric Kaplan-Meier cumulative survivorship estimates were used to assess the median timing of natural menopause. Cox proportional hazards regression models were employed to estimate the associations between age at natural menopause and exposure variables. The overall median age at natural menopause was 50 years. In the adjusted Cox model, current smoking (hazard ratio [HR], 1.11; 95% CI, 1.01-1.23) and underweight (HR, 1.34; 95% CI, 1.12-1.61) were associated with earlier natural menopause. Conversely, performing recommended levels of physical activity in the last week (HR, 0.88; 95% CI, 0.80-0.97), being overweight (HR 0.86; 95% CI, 0.74-0.99), and adhering to two or three healthy eating markers (HR, 0.80; 95% CI, 0.66-0.97; HR, 0.76; 95% CI, 0.61-0.94, respectively) were associated with later age at natural menopause. Binge drinking and waist circumference were not associated with age at natural menopause. Lifestyle, anthropometric, and dietary characteristics are significant factors that affect the age at natural menopause. Our findings can contribute to public policies targeted at Brazilian women's health.

Age of Diabetes Diagnosis and Lifetime Risk of Dementia: The Atherosclerosis Risk in Communities (ARIC) Study.

The impact of age of diabetes diagnosis on dementia risk across the life course is poorly characterized. We estimated the lifetime risk of dementia by age of diabetes diagnosis. We included 13,087 participants from the Atherosclerosis Risk in Communities Study who were free from dementia at age 60 years. We categorized participants as having middle age-onset diabetes (diagnosis <60 years), older-onset diabetes (diagnosis 60-69 years), or no diabetes. Incident dementia was ascertained via adjudication and active surveillance. We used the cumulative incidence function estimator to characterize the lifetime risk of dementia by age of diabetes diagnosis while accounting for the competing risk of mortality. We used restricted mean survival time to calculate years lived without and with dementia. Among 13,087 participants, there were 2,982 individuals with dementia and 4,662 deaths without dementia during a median follow-up of 24.1 (percentile 25-percentile 75, 17.4-28.3) years. Individuals with middle age-onset diabetes had a significantly higher lifetime risk of dementia than those with older-onset diabetes (36.0% vs. 31.0%). Compared with those with no diabetes, participants with middle age-onset diabetes also had a higher cumulative incidence of dementia by age 80 years (16.1% vs. 9.4%) but a lower lifetime risk (36.0% vs. 45.6%) due to shorter survival. Individuals with middle age-onset diabetes developed dementia 4 and 1 years earlier than those without diabetes and those with older-onset diabetes, respectively. Preventing or delaying diabetes may be an important approach for reducing dementia risk throughout the life course.

Methodologies for the collection of parameters to estimate dust/soil ingestion for young children.

Heavy metals, pesticides and a host of contaminants found in dust and soil pose a health risk to young children through ingestion. Dust/soil ingestion rates for young children can be estimated using micro-level activity time series (MLATS) as model inputs. MLATS allow for the generation of frequency and duration of children's contact activities, along with sequential contact patterns. Models using MLATS consider contact types, and transfer dynamics to assign mechanisms of contact and appropriate exposure factors for cumulative estimates of ingestion rates. The objective of this study is to describe field implementation, data needs, advanced field collection, laboratory methodologies, and challenges for integrating into and updating a previously validated physical-stochastic MLATS-based model framework called the Child-Specific Aggregate Cumulative Human Exposure and Dose (CACHED) model. The manuscript focuses on describing the methods implemented in the current study. This current multidisciplinary study (Dust Ingestion childRen sTudy [DIRT]) was implemented across three US regions: Tucson, Arizona; Miami, Florida and Greensboro, North Carolina. Four hundred and fifty participants were recruited between August 2021 to June 2023 to complete a 4-part household survey, of which 100 also participated in a field study. The field study focused on videotaping children's natural play using advanced unattended 360° cameras mounted for participants' tracking and ultimately conversion to MLATS. Additionally, children's hand rinses were collected before and after recording, along with indoor dust and outdoor soil, followed by advanced mass analysis. The gathered data will be used to quantify dust/soil ingestion by region, sociodemographic variables, age groups (from 6 months to 6 years), and other variables for indoor/outdoor settings within an adapted version of the CACHED model framework. New innovative approaches for the estimation of dust/soil ingestion rates can potentially improve modeling and quantification of children's risks to contaminants from dust exposure.

The introduction of video-enabled directly observed therapy (video-DOT) for patients with drug-resistant TB disease in Eswatini amid the COVID-19 pandemic – a retrospective cohort study

BackgroundVideo-enabled directly observed therapy (video-DOT) has been proposed as an additional option for treatment provision besides in-person DOT for patients with drug-resistant TB (DRTB) disease. However, evidence and implementation experience mainly originate from well-resourced contexts. This study describes the operationalization of video-DOT in a low-resourced setting in Eswatini facing a high burden of HIV and TB amid the emergence of the COVID-19 pandemic.MethodsThis is a retrospectively established cohort of patients receiving DRTB treatment during the implementation of video-DOT in Shiselweni from May 2020 to March 2022. We described intervention uptake (vs. in-person DOT) and assessed unfavorable DRTB treatment outcome (death, loss to care) using Kaplan-Meier statistics and multivariable Cox-regression models. Video-related statistics were described with frequencies and medians. We calculated the fraction of expected doses observed (FEDO) under video-DOT and assessed associations with missed video uploads using multivariable Poisson regression analysis.ResultsOf 71 DRTB patients eligible for video-DOT, the median age was 39 (IQR 30–54) years, 31.0% (n = 22) were women, 67.1% (n = 47/70) were HIV-positive, and 42.3% (n = 30) were already receiving DRTB treatment when video-DOT became available. About half of the patients (n = 37; 52.1%) chose video-DOT, mostly during the time when COVID-19 appeared in Eswatini. Video-DOT initiations were lower in new DRTB patients (aHR 0.24, 95% CI 0.12–0.48) and those aged ≥ 60 years (aHR 0.27, 95% CI 0.08–0.89). Overall, 20,634 videos were uploaded with a median number of 553 (IQR 309–748) videos per patient and a median FEDO of 92% (IQR 84–97%). Patients aged ≥ 60 years were less likely to miss video uploads (aIRR 0.07, 95% CI 0.01–0.51). The cumulative Kaplan-Meier estimate of an unfavorable treatment outcome among all patients was 0.08 (95% CI 0.03–0.19), with no differences detected by DOT approach and other baseline factors in multivariable analysis.ConclusionsImplementing video-DOT for monitoring of DRTB care provision amid the intersection of the HIV and COVID-19 pandemics seemed feasible. Digital health technologies provide additional options for patients to choose their preferred way to support treatment taking, thus possibly increasing patient-centered health care while sustaining favorable treatment outcomes.

Long-term survival of resurfacing humeral hemiarthroplasty

IntroductionThe indication for shoulder resurfacing arthroplasty is controversial, and survival of these implants is somewhat inconsistent. This study aimed to evaluate the long-term survivorship of resurfacing humeral head implants (RHHIs) and determine risk factors for complications and revisions.Materials and methodsThis retrospective cohort study consisted of 275 cases and two types of RHHIs. The survival rate was evaluated using the Kaplan–Meier method and Cox regression for risk factor analysis. Demographic factors were studied, and the change in the humerus centre of rotation (COR) was measured.ResultsThe mean follow-up time was 8.7 years (SD 2.7 months, range 2.8–15.9 years). The mean age of the patients was 67.6 years (SD 9.6, range 33.5–84.9). Ten-year cumulative RHHI survival was 94.1%. The cumulative estimate without any complication was 98.9% at 5 years, 80.0% at 10 years and at 15 years it was 61.5%. The most common complication was persistent pain in 13.8% of the RHHIs. The risk factors for complications and revisions were implant type, preoperative conditions and change of COR > 5 mm.ConclusionsRRHIs showed excellent long-term survival, but many complications were found. The most common complication was persistent pain, which seemed to be caused by a change of COR and was more related to one type of implant.

#529 Educational level and mortality in patients receiving chronic hemodialysis in Lazio Region—Italy

Abstract Background and Aims In 2010, 2.6 million people received Kidney Replacement Treatment (KRT) worldwide. Hemodialysis (HD) is the most commonly used KRT. HD patients have a consistent risk of death. The impact of Educational Level (Edl) on the mortality in HD patients is unclear. This study aims to analyse the association between the Edls and mortality in incident chronic HD patients using the Lazio Regional Dialysis and Transplant Registry. Method A cohort of incident HD patients between 2008 and 2022 was selected. Patients under 18 years old and with a follow-up period shorter than 91 days were excluded. All patients were characterized by sociodemographic and clinical characteristics at the incident date and were followed from the incident date until the earliest of the following dates: death, transplantation, renal function recovery or end of the study (one or three years after initiation). One-year and three-year Crude Mortality Rates*100 Person Years (CMR*100PY) overall and by Edal (low: up to primary school, medium: secondary school, high: university degree and more) were calculated. Cumulative survival estimates at one year and three years since starting HD, were presented as Kaplan-Meier curves by EdL and compared using the log-rank test. Crude and adjusted Hazard Ratios (HR) and respective 95% Confidence Intervals (95% CI) of the association between EdL and one and three-year mortality were calculated using univariate and multivariate Cox regression models (reference category: low EdL). Sociodemographic and clinical characteristics were considered potential confounders or effect modifiers in the adjusted Cox regression models. Results The cohort counted 9,776; 33.5% had a low EdL, 30.7% had a medium, and 35.8% had a high EdL. The mean age decreased with increasing EdL (73 and 65 in low and high EdL, respectively) as the proportion of females (43.0% and 26.0% in low and high EdL, respectively). During the first year of HD, 1,683 deaths occurred, and 3,827 occurred within three years. One-year CMR*100PY were 24.1 (95% CI 22.4-26.0) in low EdL, 17.4 (95% CI: 15.9-19.0) in medium EdL and 15.0 (95% CI: 13.8-16.4) in high ED. The corresponding three-year CMR were 22.7 (95% CI 21.6-23.8), 17.4 (95% CI 16.4-18.4) and 15.1 (95% CI 14.2-16.0). One-year survivals estimates were 78.0% in low EdL, 83.8% in medium and 85.8% in high EdL (log-rank test: p-value &amp;lt; 0.001). The three-years survival estimates were 51.0% in low EdL, 59.3% in medium EdL and 63.7% in high EdL (log-rank test: p-value &amp;lt; 0.001). In one-year mortality the crude HRs were 0.72 (95% CI: 0.64–0.81) and 0.62 (95% CI: 0.55–0.70) of medium and high EdL vs. low EdL respectively; the corresponding adjusted HRs were 0.93 (95% CI: 0.83–1.06) and 0.92 (95% CI: 0.81–1.04) (Fig. 1). Similar results were obtained for three-year mortality: crude HRs were 0.77 (95% CI: 0.71–0.83) and 0.66 (95% CI: 0.62–0.72); adjusted HRs were 0.99 (95% CI: 0.92–1.08) and 0.97 (95% CI: 0.89–1.06), respectively (Fig. 2).). Conclusion Based on the present study, high educational level does not appear to be associated with lower mortality risk at either one-year or three-years. Hemodialysis patients are constantly monitored by National Health Service; this probably cancels the effect of low educational level on mortality. Although EdL is a strong indicator of socioeconomic position, it does not capture all dimensions of disadvantage. The mechanisms that underline the poor prognosis in Haemodialysis patients are complex and further investigations are needed.