Category: Statistics

Ann Thorac Surg. 2023 Jul 8:S0003-4975(23)00693-8. doi: 10.1016/j.athoracsur.2023.06.024. Online ahead of print.

ABSTRACT

BACKGROUND: We aim to longitudinally compare expanded-polytetrafluoroethylene (ePTFE) valved vs pulmonary homograft (PH) conduits after right ventricular outflow tract reconstruction in the Ross procedure.

METHODS: We identified patients undergoing a Ross procedure from June 2004 to December 2021. Echocardiographic data, catheter-based interventions or conduit replacement as well as time to first reintervention or replacement were comparatively assessed between handmade ePTFE-valved and PH conduits.

RESULTS: A total of 90 patients were identified. The median age, and weight were 13.8 years (IQR 8.08-17.80) and 48.3 kg (IQR 26.8-68.7). There were 66% (n=60) ePTFE-valved conduits and 33% (n=30) PH. The median size was 22 mm (IQR 18-24) for ePTFE-valved conduits and 25 mm (IQR 23-26) for PH conduits (p<0.001). Conduit type has no differential effect in the gradient evolution or the odds of presenting with severe regurgitation in the last follow-up echocardiogram. Out of the 26 first reinterventions, 81% were catheter-based interventions, without statistically significant differences between the groups (69% PH vs. 83% ePTFE). The overall surgical conduit replacement was 15% (n=14), being higher in the homograft group (30% vs 8%; p=0.008). However, conduit type was not associated with increased hazard for reintervention or reoperation after adjusting for covariates.

CONCLUSIONS: RVOT reconstruction using handmade ePTFE-valvedconduits after a Ross procedure provides encouraging midterm results, without a differential effect in hemodynamic performance or valve function compared to PH. These results reassure the utilization of handmade valved conduits in pediatric population and young adults. Longer follow-up of tricuspid conduits will complement valve competency assessment.

PMID:37429515 | DOI:10.1016/j.athoracsur.2023.06.024

J Biomed Inform. 2023 Jul 8:104440. doi: 10.1016/j.jbi.2023.104440. Online ahead of print.

ABSTRACT

The imputation of missing values in multivariate time series (MTS) data is a critical step in ensuring data quality and producing reliable data-driven predictive models. Apart from many statistical approaches, a few recent studies have proposed state-of-the-art deep learning methods to impute missing values in MTS data. However, the evaluation of these deep methods is limited to one or two data sets, low missing rates, and completely random missing value types. This survey performs six data-centric experiments to benchmark state-of-the-art deep imputation methods on five time series health data sets. Our extensive analysis reveals that no single imputation method outperforms the others on all five data sets. The imputation performance depends on data types, individual variable statistics, missing value rates, and types. Deep learning methods that jointly perform cross-sectional (across variables) and longitudinal (across time) imputations of missing values in time series data yield statistically better data quality compared to traditional imputation methods. Although computationally expensive, deep learning methods are practical given the current availability of high-performance computing resources, especially when data quality and sample size are highly important in healthcare informatics. Our findings highlight the importance of data-centric selection of imputation methods to optimize data-driven predictive models.

PMID:37429511 | DOI:10.1016/j.jbi.2023.104440

J Endod. 2023 Jul 8:S0099-2399(23)00391-6. doi: 10.1016/j.joen.2023.07.002. Online ahead of print.

ABSTRACT

INTRODUCTION: This study evaluated the effects of diabetes mellitus (DM) on the nanostructure of root canal dentin using high-resolution transmission electron microscopy (HRTEM) and inductively coupled plasma mass spectrometry (ICP-MS).

METHODS: Twenty extracted human premolars from diabetic and non-diabetic patients (n=10 in each group) were decoronated and sectioned horizontally into forty 2-mm-thick dentin discs, with each disc designated for a specific test. ICP-MS was used to determine the different elemental levels of Cu, Li, Zn, Se, Sr, Mn, and Mg in diabetic and non-diabetic specimens. HRTEM was used to analyze the shape and quantity of the apatite crystals in diabetic and non-diabetic dentin at the nanostructural level. Statistical analysis was performed using Kolmogorov-Smirnov and student’s t-test (p<0.05).

RESULTS: ICP-MS revealed significant differences in trace element concentrations between the diabetic and non-diabetic specimens (p<0.05), with lower levels of Mg, Zn, Sr, Li, Mn, and Se (p<0.05), and higher levels of Cu in diabetic specimens (p<0.05). HRTEM revealed that diabetic dentin exhibited a less compact structure with smaller crystallites and significantly more crystals in the 2500 nm² area (p<0.05).

CONCLUSION: Diabetic dentin exhibited smaller crystallites and altered elemental levels than non-diabetic dentin, which could explain the higher root canal treatment failure rate in diabetic patients.

PMID:37429496 | DOI:10.1016/j.joen.2023.07.002

Clin Biomech (Bristol, Avon). 2023 Jul 6;107:106040. doi: 10.1016/j.clinbiomech.2023.106040. Online ahead of print.

ABSTRACT

BACKGROUND: Rotator cuff muscles are responsible for humeral rotation. Moment arms of different regions of these muscles during humeral rotation were analyzed in neutral and abducted positions.

METHODS: In eight cadaveric shoulders, subregions of the rotator cuff muscles were identified and their excursion during humeral rotation was measured in neutral and abducted positions from an internal rotation of 30° to an external rotation of 45°, with 15° increments, using a 3-D digitizing system. Statistical tests were used to assess differences between subregions within a single muscle.

FINDINGS: The posterior-deep subregion of the supraspinatus muscle had greater moment arms compared to the anterior-superficial and anterior-middle subregions in both positions (p < 0.001). The middle and inferior subregions of the infraspinatus muscle and the teres minor muscle showed differences in moment arms compared to the superior region in an abducted position (p < 0.042). The superior subregion of the subscapularis muscle showed differences in moment arms compared to the middle and inferior subregions in an abducted position (p < 0.001).

INTERPRETATION: The posterior-deep subregion of the supraspinatus muscle behaved similar to the infraspinatus muscle, as an external rotator. The anterior-superficial and anterior-middle subregions of the supraspinatus muscle showed a biphasic behavior during rotation at a neutral position, but acted as pure external rotators during rotation at an abducted position. Inferior subregions of the infraspinatus and subscapularis muscles showed the largest moment arms compared to superior subregions. These findings support distinct functional roles of the rotator cuff muscle subregions.

PMID:37429101 | DOI:10.1016/j.clinbiomech.2023.106040

Am J Cardiol. 2023 Jul 8;202:119-130. doi: 10.1016/j.amjcard.2023.06.066. Online ahead of print.

ABSTRACT

Iron deficiency is an independent risk factor for heart failure (HF) exacerbation. We aim to study the safety and efficacy of intravenous (IV) iron therapy in patients with HF with reduced ejection fraction (HFrEF). A literature search was conducted on MEDLINE (Embase and PubMed) using a systematic search strategy by PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) until October 2022. CRAN-R software (The R Foundation for Statistical Computing, Vienna, Austria) was used for statistical analysis. The quality assessment was performed using the Cochrane Risk of Bias and Newcastle-Ottawa Scale. We included 12 studies with a total of 4,376 patients (IV iron n = 1,985 [45.3%]; standard of care [SOC] n = 2,391 [54.6%]). The mean age was 70.37 ± 8.14 years and 71.75 ± 7.01 years in the IV iron and SOC groups, respectively. There was no significant difference in all-cause mortality and cardiovascular mortality (risk ratio [RR] 0.88, 95% confidence interval [CI] 0.74 to 1.04, p <0.15). However, HF readmissions were significantly lower in the IV iron group (RR 0.73, 95% CI 0.56 to 0.96, p = 0.026). Non-HF cardiac readmissions were not significantly different between the IV iron and SOC groups (RR 0.92, 95% CI 0.82 to 1.02, p = 0.12). In terms of safety, there was a similar rate of infection-related adverse events in both arms (RR 0.86, 95% CI 0.74 to 1, p = 0.05). IV iron therapy in patients with HFrEF is safe and shows a significant reduction in HF hospitalizations compared with SOC. There was no difference in the rate of infection-related adverse events. The changing landscape of HFrEF pharmacotherapy in the last decade may warrant a re-demonstration of the benefit of IV iron with current SOC. The cost-effectiveness of IV iron use also needs further study.

PMID:37429060 | DOI:10.1016/j.amjcard.2023.06.066

Poult Sci. 2023 Jul 1;102(9):102902. doi: 10.1016/j.psj.2023.102902. Online ahead of print.

ABSTRACT

Driven by a global trend of applying replace-reduce-refine or 3Rs’ guidance for experimental animals in life sciences, chick embryo and particularly allantois with its chorioallantoic membrane have been increasingly utilized to substitute laboratory animals, which call for more extensive and updated knowledge about this novel experimental setup. In this study, being noninvasive, nonionizing, and super-contrasting with high spatiotemporal resolutions, magnetic resonance imaging (MRI) was chosen as an imaging modality for in ovo monitoring morphologic evolution of the chick embryo, allantois, and chorioallantoic membrane longitudinally throughout embryonic day (ED) 1 until ED20. Cooled in 0°C ice bath for 60 min to reduce MRI motion artifacts, 3 chick embryos (n = 60 in total) on each ED were scanned by a clinical 3.0T MRI scanner to demonstrate 3D images of both T2- and T1-weighted imaging (T2WI, T1WI) sequences at axial, sagittal, and coronal slices. The volumes of both the entire chick embryo and allantois were semi-automatically segmented based on intensity-based thresholding and region-growing algorithms. The morphometries or quantified 3D structures were achieved by refined segmentation, and confirmed by histological analyses (one for each ED). After MRI, the rest of chick embryos (n = 40) continued for incubation. The images from ED2 to ED4 could demonstrate the structural changes of latebra, suggesting its transition into a nutrient supplying channel of yolk sac. The allantois could be recognized by MRI, and its relative volumes on each ED revealed an evolving profile peaked on ED12, with a statistically significant difference from those of earlier and later EDs (P < 0.01). The hypointensity of the yolk due to the susceptibility effect of its enriched iron content overshadowed the otherwise hyperintensity of its lipid components. The chick embryos survived prior cooling and MRI till hatching on ED21. The results could be further developed into a 3D MRI atlas of chick embryo. Clinical 3.0T MRI proved effective as a noninvasive approach to study in ovo 3D embryonic development across the full period (ED1-ED20), which can complement the present knowhow for poultry industry and biomedical science.

PMID:37429051 | DOI:10.1016/j.psj.2023.102902

Ann Intern Med. 2023 Jul 11. doi: 10.7326/M22-2504. Online ahead of print.

ABSTRACT

BACKGROUND: Medical groups, health systems, and professional associations are concerned about potential increases in physician turnover, which may affect patient access and quality of care.

OBJECTIVE: To examine whether turnover has changed over time and whether it is higher for certain types of physicians or practice settings.

DESIGN: The authors developed a novel method using 100% of traditional Medicare billing to create national estimates of turnover. Standardized turnover rates were compared by physician, practice, and patient characteristics.

SETTING: Traditional Medicare, 2010 to 2020.

PARTICIPANTS: Physicians billing traditional Medicare.

MEASUREMENTS: Indicators of physician turnover-physicians who stopped practicing and those who moved from one practice to another-and their sum.

RESULTS: The annual rate of turnover increased from 5.3% to 7.2% between 2010 and 2014, was stable through 2017, and increased modestly in 2018 to 7.6%. Most of the increase from 2010 to 2014 came from physicians who stopped practicing increasing from 1.6% to 3.1%; physicians moving increased modestly from 3.7% to 4.2%. Modest but statistically significant (P < 0.001) differences existed across rurality, physician sex, specialty, and patient characteristics. In the second and third quarters of 2020, quarterly turnover was slightly lower than in the corresponding quarters of 2019.

LIMITATION: Measurement was based on traditional Medicare claims.

CONCLUSION: Over the past decade, physician turnover rates have had periods of increase and stability. These early data, covering the first 3 quarters of 2020, give no indication yet of the COVID-19 pandemic increasing turnover, although continued tracking of turnover is warranted. This novel method will enable future monitoring and further investigations into turnover.

PRIMARY FUNDING SOURCE: The Physicians Foundation Center for the Study of Physician Practice and Leadership.

PMID:37429029 | DOI:10.7326/M22-2504

JAMA Otolaryngol Head Neck Surg. 2023 Jul 10. doi: 10.1001/jamaoto.2023.1975. Online ahead of print.

ABSTRACT

IMPORTANCE: Standard cancer prognosis models typically do not include much specificity in characterizing competing illnesses or general health status when providing prognosis estimates, limiting their utility for individuals, who must consider their cancer in the context of their overall health. This is especially true for patients with oral cancer, who frequently have competing illnesses.

OBJECTIVE: To describe a statistical framework and accompanying new publicly available calculator that provides personalized estimates of the probability of a patient surviving or dying from cancer or other causes, using oral cancer as the first data set.

DESIGN, SETTING, AND PARTICIPANTS: The models used data from the Surveillance, Epidemiology, and End Results (SEER) 18 registry (2000 to 2011), SEER-Medicare linked files, and the National Health Interview Survey (NHIS) (1986 to 2009). Statistical methods developed to calculate natural life expectancy in the absence of the cancer, cancer-specific survival, and other-cause survival were applied to oral cancer data and internally validated with 10-fold cross-validation. Eligible participants were aged between 20 and 94 years with oral squamous cell carcinoma.

EXPOSURES: Histologically confirmed oral cancer, general health status, smoking, and selected serious comorbid conditions.

MAIN OUTCOMES AND MEASURES: Probabilities of surviving or dying from the cancer or from other causes, and life expectancy in the absence of the cancer.

RESULTS: A total of 22 392 patients with oral squamous cell carcinoma (13 544 male [60.5%]; 1476 Asian and Pacific Islander [6.7%]; 1792 Black [8.0%], 1589 Hispanic [7.2%], 17 300 White [78.1%]) and 402 626 NHIS interviewees were included in this calculator designed for public use for patients ages 20 to 86 years with newly diagnosed oral cancer to obtain estimates of health status-adjusted age, life expectancy in the absence of the cancer, and the probability of surviving, dying from the cancer, or dying from other causes within 1 to 10 years after diagnosis. The models in the calculator estimated that patients with oral cancer have a higher risk of death from other causes than their matched US population, and that this risk increases by stage.

CONCLUSIONS AND RELEVANCE: The models developed for the calculator demonstrate that survival estimates that exclude the effects of coexisting conditions can lead to underestimates or overestimates of survival. This new calculator approach will be broadly applicable for developing future prognostic models of cancer and noncancer aspects of a person’s health in other cancers; as registries develop more linkages, available covariates will become broader, strengthening future tools.

PMID:37429022 | DOI:10.1001/jamaoto.2023.1975

JAMA Otolaryngol Head Neck Surg. 2023 Jul 10. doi: 10.1001/jamaoto.2023.1977. Online ahead of print.

ABSTRACT

IMPORTANCE: In the setting of a new cancer diagnosis, the focus is usually on the cancer as the main threat to survival, but people may have other conditions that pose an equal or greater threat to their life than their cancer: a competing risk of death. This is especially true for patients who have cancer of the oral cavity, because prolonged exposure to alcohol and tobacco are risk factors for cancer in this location but also can result in medical conditions with the potential to shorten life expectancy, competing as a cause of death that may intervene in conjunction with or before the cancer.

OBSERVATIONS: A calculator designed for public use has been released that allows patients age 20 to 86 years who have a newly diagnosed oral cancer to obtain estimates of their health status-adjusted age, life expectancy in the absence of the cancer, and probability of surviving, dying of the cancer, or dying of other causes within 1 to 10 years after diagnosis. The models in the calculator showed that patients with oral cavity cancer had a higher than average risk of death from other causes than the matched US population, and this risk increases by stage.

CONCLUSIONS AND RELEVANCE: The Surveillance, Epidemiology and End Results Program Oral Cancer Survival Calculator supports a holistic approach to the life of the patient, and the risk of death of other causes is treated equally to consideration of the probability of death of the cancer. This tool may be usefully paired with the other available prognostic calculators for oral cancer and is an example of the possibilities now available with registry linkages to partially overlapping or independent data sets and statistical techniques that allow the use of 2 time scales in 1 analysis.

PMID:37429019 | DOI:10.1001/jamaoto.2023.1977

Prehosp Emerg Care. 2023 Jul 10:1-14. doi: 10.1080/10903127.2023.2234996. Online ahead of print.

ABSTRACT

Introduction: Pediatric asthma exacerbations are a common cause of emergency medical services (EMS) encounters. Bronchodilators and systemic corticosteroids are mainstays of asthma exacerbation therapy, yet data on the efficacy of EMS administration of systemic corticosteroids are mixed. This study’s objective was to assess the association between EMS administration of systemic corticosteroids to pediatric asthma patients on hospital admission rates based on asthma exacerbation severity and EMS transport intervals.Methods: This is a sub-analysis of the Early Administration of Steroids in the Ambulance Setting: An Observational Design Trial (EASI AS ODT). EASI AS ODT is a non-randomized, stepped wedge, observational study examining outcomes one year before and one year after seven EMS agencies incorporated an oral systemic corticosteroid option into their protocols for the treatment of pediatric asthma exacerbations. We included EMS encounters for patients ages 2 – 18 years confirmed by manual chart review to have asthma exacerbations. We compared hospital admission rates across asthma exacerbation severities and EMS transport intervals using univariate analyses. We geocoded patients and created maps to visualize the general trends of patient characteristics.Results: A total of 841 pediatric asthma patients met inclusion criteria. While most patients were administered inhaled bronchodilators by EMS (82.3%), only 21% received systemic corticosteroids, and only 19% received both inhaled bronchodilators and systemic corticosteroids. Overall, there was no significant difference in hospitalization rates between patients who did and did not receive systemic corticosteroids from EMS (33% vs. 32%, p = 0.78). However, although not statistically significant, for patients who received systemic corticosteroids from EMS, there was an 11% decrease in hospitalizations for mild exacerbation patients and a 16% decrease in hospitalizations for patients with EMS transport intervals greater than 40 minutes.Conclusion: In this study, systemic corticosteroids were not associated with a decrease in hospitalizations of pediatric patients with asthma overall. However, while limited by small sample size and lack of statistical significance, our results suggest there may be a benefit in certain subgroups, particularly patients with mild exacerbations and those with transport intervals longer than 40 minutes. Given the heterogeneity of EMS agencies, EMS agencies should consider local operational and pediatric patient characteristics when developing standard operating protocols for pediatric asthma.

PMID:37428954 | DOI:10.1080/10903127.2023.2234996