Category: Statistics

Lifetime Data Anal. 2024 Oct 23. doi: 10.1007/s10985-024-09640-z. Online ahead of print.

ABSTRACT

We propose a two-stage estimation procedure for a copula-based model with semi-competing risks data, where the non-terminal event is subject to dependent censoring by the terminal event, and both events are subject to independent censoring. With a copula-based model, the marginal survival functions of individual event times are specified by semiparametric transformation models, and the dependence between the bivariate event times is specified by a parametric copula function. For the estimation procedure, in the first stage, the parameters associated with the marginal of the terminal event are estimated using only the corresponding observed outcomes, and in the second stage, the marginal parameters for the non-terminal event time and the copula parameter are estimated together via maximizing a pseudo-likelihood function based on the joint distribution of the bivariate event times. We derived the asymptotic properties of the proposed estimator and provided an analytic variance estimator for inference. Through simulation studies, we showed that our approach leads to consistent estimates with less computational cost and more robustness than the one-stage procedure developed in Chen YH (Lifetime Data Anal 18:36-57, 2012), where all parameters were estimated simultaneously. In addition, our approach demonstrates more desirable finite-sample performances over another existing two-stage estimation method proposed in Zhu H et al., (Commu Statistics-Theory Methods 51(22):7830-7845, 2021) . An R package PMLE4SCR is developed to implement our proposed method.

PMID:39441437 | DOI:10.1007/s10985-024-09640-z

J Clin Immunol. 2024 Oct 23;45(1):32. doi: 10.1007/s10875-024-01818-2.

ABSTRACT

Distinguishing between primary (PID) and secondary (SID) immunodeficiencies, particularly in relation to hematological B-cell lymphoproliferative disorders (B-CLPD), poses a major clinical challenge. We aimed to analyze and define the clinical and laboratory variables in SID patients associated with B-CLPD, identifying overlaps with late-onset PIDs, which could potentially improve diagnostic precision and prognostic assessment. We studied 37 clinical/laboratory variables in 151 SID patients with B-CLPD. Patients were classified as “Suspected PID Group” when having recurrent-severe infections prior to the B-CLPD and/or hypogammaglobulinemia according to key ESID criteria for PID. Bivariate association analyses showed significant statistical differences between “Suspected PID”- and “SID”-groups in 10 out of 37 variables analyzed, with “Suspected PID” showing higher frequencies of childhood recurrent-severe infections, family history of B-CLPD, significantly lower serum Free Light Chain (sFLC), immunoglobulin concentrations, lower total leukocyte, and switch-memory B-cell counts at baseline. Rpart machine learning algorithm was performed to potentially create a model to differentiate both groups. The model developed a decision tree with two major variables in order of relevance: sum κ + λ and history of severe-recurrent infections in childhood, with high sensitivity 89.5%, specificity 100%, and accuracy 91.8% for PID prediction. Identifying significant clinical and immunological variables can aid in the difficult task of recognizing late-onset PIDs among SID patients, emphasizing the value of a comprehensive immunological evaluation. The differences between “Suspected PID” and SID groups, highlight the need of early, tailored diagnostic and treatment strategies for personalized patient management and follow up.

PMID:39441407 | DOI:10.1007/s10875-024-01818-2

Arch Gynecol Obstet. 2024 Oct 23. doi: 10.1007/s00404-024-07783-w. Online ahead of print.

ABSTRACT

PURPOSE: To examine the relationship between quality of life (QoL) and chronic pelvic pain (CPP), including an evaluation of whether differences exist between reported races and coping mechanisms used.

METHODS: We used a cross-sectional survey design and analyzed data using descriptive and inferential statistics. We administered two surveys: the World Health Organization Quality of Life-BREF (26 items) and the Impact of Female Chronic Pelvic Pain Questionnaire (8 items). We recruited young adults aged 18-25 who menstruate from college campuses in a large metropolitan area in the Midwest region of the United States, utilizing flyers, online social media platforms, and snowball sampling techniques.

RESULTS: Out of the 585 respondents, 153 (26%) reported “yes,” and 95 (16%) were “unsure” they had CPP. Those with CPP and unsure reported using various coping mechanisms for pain. They had lower scores in all four domains (physical health, psychological, social relationship, and environment) and statistically significant lower scores in three domains (physical health, social relationship, and environment) on the World Health Organization Quality of Life-BREF when compared to those who said “no.” Respondents identifying as Black, Indigenous, or People of Color had statistically significantly lower QoL in the physical health and environment domains compared to white respondents.

CONCLUSION: Young adults with CPP experience a significantly lower QoL than those without CPP, and racial differences further widen this gap. Future research should explore coping mechanisms that could benefit young adults’ daily lives.

PMID:39441406 | DOI:10.1007/s00404-024-07783-w

Eur Radiol. 2024 Oct 23. doi: 10.1007/s00330-024-11145-0. Online ahead of print.

ABSTRACT

OBJECTIVES: To compare standard-resolution balanced steady-state free precession (bSSFP) cine images with cine images acquired at low resolution but reconstructed with a deep learning (DL) super-resolution algorithm.

MATERIALS AND METHODS: Cine cardiovascular magnetic resonance (CMR) datasets (short-axis and 4-chamber views) were prospectively acquired in healthy volunteers and patients at normal (cine_NR: 1.89 × 1.96 mm², reconstructed at 1.04 × 1.04 mm²) and at a low-resolution (2.98 × 3.00 mm², reconstructed at 1.04 × 1.04 mm²). Low-resolution images were reconstructed using compressed sensing DL denoising and resolution upscaling (cine_DL). Left ventricular ejection fraction (LVEF), end-diastolic volume index (LVEDVi), and strain were assessed. Apparent signal-to-noise (aSNR) and contrast-to-noise ratios (aCNR) were calculated. Subjective image quality was assessed on a 5-point Likert scale. Student’s paired t-test, Wilcoxon matched-pairs signed-rank-test, and intraclass correlation coefficient (ICC) were used for statistical analysis.

RESULTS: Thirty participants were analyzed (37 ± 16 years; 20 healthy volunteers and 10 patients). Short-axis views whole-stack acquisition duration of cine_DL was shorter than cine_NR (57.5 ± 8.7 vs 98.7 ± 12.4 s; p < 0.0001). No differences were noted for: LVEF (59 ± 7 vs 59 ± 7%; ICC: 0.95 [95% confidence interval: 0.94, 0.99]; p = 0.17), LVEDVi (85.0 ± 13.5 vs 84.4 ± 13.7 mL/m²; ICC: 0.99 [0.98, 0.99]; p = 0.12), longitudinal strain (-19.5 ± 4.3 vs -19.8 ± 3.9%; ICC: 0.94 [0.88, 0.97]; p = 0.52), short-axis aSNR (81 ± 49 vs 69 ± 38; p = 0.32), aCNR (53 ± 31 vs 45 ± 27; p = 0.33), or subjective image quality (5.0 [IQR 4.9, 5.0] vs 5.0 [IQR 4.7, 5.0]; p = 0.99).

CONCLUSION: Deep-learning reconstruction of cine images acquired at a lower spatial resolution led to a decrease in acquisition times of 42% with shorter breath-holds without affecting volumetric results or image quality.

KEY POINTS: Question Cine CMR acquisitions are time-intensive and vulnerable to artifacts. Findings Low-resolution upscaled reconstructions using DL super-resolution decreased acquisition times by 35-42% without a significant difference in volumetric results or subjective image quality. Clinical relevance DL super-resolution reconstructions of bSSFP cine images acquired at a lower spatial resolution reduce acquisition times while preserving diagnostic accuracy, improving the clinical feasibility of cine imaging by decreasing breath hold duration.

PMID:39441391 | DOI:10.1007/s00330-024-11145-0

Sud Med Ekspert. 2024;67(5):10-14. doi: 10.17116/sudmed20246705110.

ABSTRACT

OBJECTIVE: To study the incidence of sudden cardiac death (SCD) among overall and primary morbidity of diseases of the circulatory system (DCS) during the COVID-19 pandemic, as well as several years before it in urban and rural populations of the Penza region.

MATERIAL AND METHODS: Statistical analysis of data using correlation (Pearson’s coefficient), regression methods, t-test was performed to determine the significance of results.

RESULTS: The higher incidence of DCS among men in urban areas has been found. COVID-19 morbidity did not cause an increase in the incidence of SCD in the rural population in comparison with primary DCS morbidity, which was strongly correlated with the prevalence of novel coronavirus infection.

PMID:39440558 | DOI:10.17116/sudmed20246705110

Sud Med Ekspert. 2024;67(5):5-9. doi: 10.17116/sudmed2024670515.

ABSTRACT

The article presents results of a retrospective analysis of the commission forensic medical examinations of «medical malpractice cases» for 2017-2021 on materials of RCFME MH KR. It has been established that the number of commission examinations showed a pronounced tendency to increase in the analyzed period: 64 (9.78%) cases – in 2017, 86 (12.63%) – in 2018, 92 (16.46%) – in 2019, 179 (29.1%) – in 2020 and 80 (13.96%) in 2021 out of 501 cases of commission examinations on «medical malpractice cases». The considerable number of ordered examinations concerned the professional activity of obstetricians-gynecologists (131 cases; 26.1%) and surgeons (65 cases; 12.9%). Quite a large part of the examinations was represented by investigations regarding COVID-19 (72 cases; 14.37%) and AIDS infection (47 cases; 9.3%) among the commission examinations. Medical violations also concerned specialists who are not related to extreme medicine (tuberculosis specialists, oncologists, therapists, neurologists).

PMID:39440557 | DOI:10.17116/sudmed2024670515

Ann Afr Med. 2024 Oct 23. doi: 10.4103/aam.aam_28_24. Online ahead of print.

ABSTRACT

BACKGROUND: Hepatitis B virus (HBV) and neonatal tetanus infections remain endemic in Nigeria despite the availability of safe, effective vaccines. We aimed to determine health facilities’ capacity for hepatitis B vaccine birth dose (HepB-BD) and maternal tetanus-diphtheria (Td) vaccination and to assess knowledge, attitudes, and practices of HepB-BD and maternal Td vaccine administration among health facility staff in Nigeria.

MATERIALS AND METHODS: This was a cross-sectional study assessing public primary and secondary health facilities in Adamawa and Enugu States. A multistage sampling approach was used to select 40 facilities and 79 health-care workers (HCWs) from each state. A structured facility assessment tool and standardized questionnaire evaluated facility characteristics and HCW knowledge, attitudes, and practices related to HepB-BD and maternal Td vaccination. Frequencies and proportions were reported as descriptive statistics.

RESULTS: The survey of 80 facilities revealed that 73.8% implemented HepB-BD and maternal Td vaccination policies. HepB-BD was administered within 24 h of birth at 61.3% of facilities and at all times at 57.5%. However, administration seldom occurred in labor and delivery (35%) or maternity wards (16.3%). Nearly half of the facilities (46.3%) had HCWs believing there were contraindications to HepB-BD vaccination. Among 158 HCWs, 26.5% believed tetanus could be transmitted through unprotected sex, prevented by vaccination at birth (46.1%), or by avoiding sharing food and utensils. 65% of HCWs knew HBV infection had the worst outcome for newborns.

CONCLUSIONS: The limited implementation of national policies on HepB-BD and maternal Td vaccination, coupled with knowledge gaps among HCWs, pose significant challenges to timely vaccination, necessitating interventions to address these gaps.

PMID:39440555 | DOI:10.4103/aam.aam_28_24

Cancer Med. 2024 Oct;13(20):e70318. doi: 10.1002/cam4.70318.

ABSTRACT

BACKGROUND: Despite remarkable progress in contemporary medical technology and enhanced survival outcomes for various cancer types, pancreatic cancer (PC) continues to stand out as a particularly deadly gastrointestinal malignancy. Given a persistent rise in both incidence and the corresponding mortality rates of PC globally, evaluations of PC burden by sex are of great importance. Here, we used the illness-death multi-state model (IDM) to forecast the prevalence of PC through the year 2040.

METHODS: IDM was established based on obtainable data to predict the future prevalence of PC on global, regional, and national scales from 2019 to 2040. Analyses were also performed regarding sex and 95% confidence intervals (CIs) are presented for all estimates.

RESULTS: The projected prevalence rate for 2040 is anticipated to be 6.093 ([95% CI 5.47-6.786] per 100,000) worldwide, indicating a significant increase of 31.45% since 1990, and a 12.29% increase since 2019. The estimated average annual increase since 2020 was 0.5%. Considering sex differences, females are expected to have a steeper slope in prevalence rate than males. Intriguingly, when considering the percentage changes between the periods of 2019-2040 and 1990-2019 for both sexes, females exhibited 29% and 11% increase relative to males (2.6-fold greater increase).

CONCLUSIONS: By 2040, it is predicted that the prevalence of PC will increase globally, with women being at higher risk of developing the disease. Considering the percentage changes, regions with lower socioeconomic status are anticipated to face a greater risk of experiencing PC compared to other geographical areas.

PMID:39440551 | DOI:10.1002/cam4.70318

Ann Afr Med. 2024 Oct 23. doi: 10.4103/aam.aam_203_23. Online ahead of print.

ABSTRACT

AIMS: We have compared sealing pressure, usability, and complications of two second-generation supraglottic airway devices-Baska® mask and I-gel.

SETTINGS AND DESIGNS: The study design involves prospective randomized controlled trial.

MATERIALS AND METHODS: The study was undertaken involving 44 patients of the American Society of Anesthesiologists physical status I and II, aged 20-70 years, who underwent surgical procedures of short duration under general anesthesia. Patients were randomly categorized into two groups of 22 each: Group B (Baska® mask) and Group I (I-gel). The main objective was to compare oropharyngeal leak pressure (OLP).

STATISTICAL ANALYSIS: Continuous variables were compared between the two groups using an unpaired t-test. Categorical variables were compared using the Chi-square test and insertion attempts using Fisher’s exact test.

RESULTS: Group B had significantly higher mean OLP (32.22 ± 2.52 cmH2O vs. 26.18 ± 2.42 cmH2O, P < 0.001). In Group I, 97.1% of patients had very easy insertion (Grade 1), 2.9% had easy insertion (Grade 2) and Group B had very easy insertion in 50% of patients, easy in 36.4%, and difficult in 13.6% of patients (P = 0.009). Group B took a longer time for successful insertion than Group I (39.89 ± 7.15 s vs. 28.19 ± 3.29 s, P < 0.001).

CONCLUSION: For positive pressure ventilation, both I-gel and Baska® masks proved to be successful, with I-gel being easier and quicker to insert. It is possible to employ the Baska® mask with superior seal pressures as an alternative to endotracheal intubation in elective surgeries if there are no patient contraindications.

PMID:39440544 | DOI:10.4103/aam.aam_203_23

Future Sci OA. 2024 Dec 31;10(1):2413827. doi: 10.1080/20565623.2024.2413827. Epub 2024 Oct 23.

ABSTRACT

Aim: Platelet-rich plasma (PRP), enriched with multiple growth factors, is a promising adjunctive therapy for diabetic foot ulcers (DFUs). As a classic anti-platelet drug for diabetic patients, the effects of aspirin on the content of growth factors in PRP remains unclear.Methods: Our study enrolled diabetic patients who were currently taking or not taking aspirin as the research subjects, with healthy volunteers as the control. PRP from these individuals was activated with glucose calcium and thrombin. Growth factors levels in PRP activated supernatant (PRP-AS) and wound healing ability of platelet gel (PG) in the full-thickness skin defect diabetic mouse model were compared.Results: We found the level of growth factors in PRP-AS derived from two groups of diabetic patients were not statistically different, whereas both lower than that from healthy volunteers. Similarly, we found better wound healing ability of PG from healthy volunteers than those from diabetic patients, but no difference between the two groups of diabetic patients in the mouse model.Discussion: Aspirin does not interfere with autologous PRP therapy when using calcium gluconate and thrombin as agonists. However considering the content of growth factors, PRP from healthy volunteers is a preferable option for promoting DFU repair.

PMID:39440536 | DOI:10.1080/20565623.2024.2413827