Category: Statistics

J Korean Med Sci. 2026 Apr 13;41(14):e113. doi: 10.3346/jkms.2026.41.e113.

ABSTRACT

BACKGROUND: Updated data on stroke care trends are crucial for advancing stroke treatment. This study aimed to assess trends in inpatient care for first-ever stroke patients in South Korea over a 12-year period, focusing on demographic shifts and acute treatments including rehabilitation.

METHODS: This multicenter cohort study analyzed first-ever stroke patients admitted to three representative hospitals in South Korea during 2008 (n = 911), 2014 (n = 1,489), and 2020 (n = 1,434). The 2008 data were collected retrospectively, while 2014 and 2020 data were obtained from a prospective cohort study. Data included demographics, risk factors, stroke characteristics, hospital course, and rehabilitation treatments.

RESULTS: From 2008 to 2020, the mean age of stroke patients increased from 62.0 to 66.2 years. The proportion of ischemic stroke cases increased markedly from 47.3% to 74.5% while risk factors such as diabetes mellitus and hyperlipidemia showed increasing prevalence. Mechanical thrombectomy increased from 0% to 3.3%. Mean hospital stay decreased from 25.2 to 14.9 days, while in-hospital mortality declined from 5.9% to 3.7%. Rehabilitation consultations increased from 27.8% to 80.6%, occurring earlier during hospitalization. Rehabilitation therapy during hospitalization increased from 23.7% to 55.8%, and transfers to rehabilitation medicine rose from 12.8% to 19.1%. Home discharge increased from 34.8% to 60.0%.

CONCLUSION: Management of first-ever stroke patients in Korea improved substantially over 12 years, reflecting positive impacts of national quality initiatives and advancing stroke care.

PMID:41978925 | DOI:10.3346/jkms.2026.41.e113

J Korean Med Sci. 2026 Apr 13;41(14):e34. doi: 10.3346/jkms.2026.41.e34.

ABSTRACT

BACKGROUND: Hybrid closed-loop (HCL) systems adjust basal insulin levels using real-time glucose levels obtained from continuous glucose monitors (CGM). This study evaluated the MiniMed 770G system in Korean youths with childhood-onset type 1 diabetes (T1D).

METHODS: Of the 457 patients followed-up for childhood-onset T1D for > 1 year at Seoul National University Children’s Hospital and Seoul National University Bundang Hospital between February 2022 and May 2023, 20 patients (10 boys, 10 girls) who used a MiniMed 770G system for ≥ 3 months with a CGM active time of > 70% were enrolled. Glycemic outcomes, including glycated hemoglobin A1c (HbA1c), and CGM-derived metrics (time in range [TIR], time below range, time above range > 180 mg/dL and > 250 mg/dL [TAR 180 and TAR 250], and coefficient of variation [CV]) were analyzed. Generalized estimating equation (GEE) analysis compared glycemic outcomes between auto-mode users (> 85% and ≤ 85%) during the 1-year follow-up.

RESULTS: The median age at HCL initiation was 14.0 years (interquartile range [IQR], 11.2, 17.9), with a median diabetes duration of 6.5 years (IQR, 5.7, 8.9). The numbers of auto-mode (> 85%) users at 3, 6, 9, and 12 months were 10, 9, 9, and 7, respectively. Compared to auto-mode (≤ 85%) users, auto-mode (> 85%) users demonstrated 0.75 lower HbA1c (P = 0.037), 7.0 higher TIR (P = 0.015), 6.7 lower TAR 180 (P = 0.031), and 3.2 lower CV (P = 0.001) during the year using GEE analysis. In an analysis of auto-mode (> 85%) users, the median TIR, TAR, and CV significantly improved from 59% at baseline to 74.5% at 3 months (P = 0.008), and from 65% at baseline to 73% at 6 months (P = 0.012). Neither severe hypoglycemia nor diabetic ketoacidosis was observed throughout the year. The most common reasons for auto-mode exit were hyperglycemia and a lack of calibration.

CONCLUSION: Use of HCL system with auto-mode (> 85%) enhanced glycemic control in youth with childhood-onset T1D during the study period.

PMID:41978923 | DOI:10.3346/jkms.2026.41.e34

J Korean Med Sci. 2026 Apr 13;41(14):e10. doi: 10.3346/jkms.2026.41.e10.

ABSTRACT

BACKGROUND: This study aims to report the nationwide risk stratification of prostate cancer (PCa) over the past decade-an analysis that has not been previously conducted, as such data are not available through the medical insurance-based big data registry of South Korea.

METHODS: Nationwide data on the clinicopathologic variables of PCa at the time of diagnosis through biopsy, prostate-specific antigen (PSA) levels, clinical stage, Gleason grade, and residential area of the patient were obtained from 51 general hospitals (with ≥ 200 beds) across South Korea in 2010, 2012, 2014, 2016, 2018, and 2020. The risk criteria were based on universal guidelines defined in the 2010s, with high risk defined as PSA levels > 20 ng/mL, clinical stage ≥ cT3a, and Gleason group (GG) ≥ 4; low risk was defined as PSA levels < 10 ng/mL, clinical stage ≤ cT2a, and GG < 1.

RESULTS: Data from 27,075 cases, representing 37.9% of the 71,403 patients registered in the National Cancer Statistics during the study period, were obtained from 51 hospitals. High-risk PCa (50.6%) was the most prevalent disease during the study period, while the proportion of low-risk diseases, including potential low-risk cases, decreased from 11.4% in 2010 to 7.6% in 2020. High-risk PCa was most prevalent in 9 of the 17 administrative regions, with 55.4% of high-risk cancer cases originating in rural areas compared to 47.7% from urban areas (P < 0.001).

CONCLUSION: Approximately 50% of the patients with PCa detected in South Korea in the 2010s had high-risk disease, which was a consistent nationwide. The higher prevalence of low-risk disease among residents of the capital metropolitan area, compared to the higher frequency of high-risk disease among rural residents, suggests disparities in access to early PCa detection and diagnosis.

PMID:41978922 | DOI:10.3346/jkms.2026.41.e10

J Int Soc Sports Nutr. 2026 Dec 31;23(1):2658171. doi: 10.1080/15502783.2026.2658171. Epub 2026 Apr 14.

ABSTRACT

BACKGROUND: The link between long-term protein intake and muscle performance in older adults has been hard to define, partly because most studies rely on short dietary windows and are vulnerable to confounding and measurement noise. In this work, we attempted to estimate the usual protein intake and functional limitation among U.S. adults aged ≥ 60 years using a target-trial emulation framework with overlap weighting and semiparametric estimators.

METHODS: Data were drawn from four NHANES survey cycles (2011-2018), including 5,736 adults aged ≥ 60 years with complete exposure, outcome, and covariate data. Usual protein intake (g/kg/day) was derived from available 24-hour recalls to approximate habitual intake. The primary outcome was PFQ-defined mobility limitation across cycles; grip strength (2011-2014) was analyzed separately as a secondary outcome. Causal contrasts across predefined intake categories (<0.8, 0.8- < 1.0, 1.0- < 1.2, ≥1.2 g/kg/day) were evaluated using covariate-balancing propensity score overlap weighting (ATO estimand) followed by marginal structural models. Doubly robust sensitivity analyses were conducted using augmented inverse probability weighting and targeted maximum likelihood estimation with generalized linear models. Simulation extrapolation (SIMEX) was applied to assess potential bias from dietary measurement error. Exploratory analyses evaluated hs-CRP as a potential mediator and tested effect modification by vitamin D status and physical activity.

RESULTS: Mean usual protein intake was 0.93 g/kg/day, and approximately 42% of participants consumed at least 0.8 g/kg/day, the current Recommended Dietary Allowance (RDA) for the general adult population. In the prespecified overlap-weighted marginal structural model (ATO estimand), higher intake was associated with lower odds of mobility limitation, although the primary contrast comparing ≥ 1.2 versus < 0.8 g/kg/day was modest and not statistically significant (OR 0.89, 95% CI 0.54-1.47). A doubly robust binary contrast yielded a -6.6 percentage-point difference in predicted limitation (95% CI -25.8 to 12.7), consistent in direction but imprecise. In cycle-specific analyses, the inverse association was more pronounced in 2015-2018 (OR 0.80, 95% CI 0.65-0.98). Spline models suggested a steeper decline in predicted limitation below approximately 1.0-1.1 g/kg/day, with a flatter trajectory at higher intakes. Exploratory mediation models indicated a potential indirect component through hs-CRP, though these estimates were not overlap-weighted and should be interpreted cautiously.

CONCLUSIONS: Higher usual protein intake was directionally associated with lower odds of mobility limitation among older U.S. adults within a target trial emulation framework, although the primary overlap-weighted estimates were modest and imprecise. Evidence of nonlinearity suggests that intakes near 1.0-1.1 g/kg/day may mark a range where predicted limitation declines more steeply, but uncertainty increases at higher intake levels. Given the cross-sectional design and residual potential for confounding, these findings should be interpreted cautiously. Prospective studies are needed to determine whether sustained protein intake in this range meaningfully preserves functional capacity over time.

PMID:41978913 | DOI:10.1080/15502783.2026.2658171

PeerJ. 2026 Apr 9;14:e21007. doi: 10.7717/peerj.21007. eCollection 2026.

ABSTRACT

Allosauroidea, Ceratosauria, Megalosauroidea, Megaraptora, and Tyrannosauroidea are five clades containing obligate faunivorous megatheropods. These clades included apex predators from the Early Jurassic until the end of the Cretaceous Period. Studying the timeline of median size class change for ceratosaurians, tyrannosauroids, and megaraptorans compared to the extinction of the incumbent apex predator clades, allosauroids and megalosauroids, is important regarding megatheropod guild structure. This study used the median size classes exhibited by these clades throughout the Jurassic and Cretaceous Periods, along with the relationship of the median number of missing size classes under different apex predatory regimes. We calculated size class medians for each clade during six discrete time bins. Statistical tests on the median size class data were run to identify potential significant differences and test if increases in median size class occurred after the Cretaceous Thermal Maximum (KTM). Statistical tests were run on the number of missing size classes for each type of apex predator regime to determine if previously proposed hypotheses may explain potential differences. Statistical differences were found between four pairs of clades and their respective median size classes. Median size class increased after the Cretaceous Thermal Maximum for tyrannosauroids and potentially megaraptorans, but increased before the Cretaceous Thermal Maximum for ceratosaurians and did not change afterwards. The median number of missing size classes was found to be higher in the abelisauroid, abelisauroid/megaraptoran, and tyrannosauroid ecosystems compared to allosauroid/megalosauroid ecosystems. The median number of missing size classes between allosauroid/megalosauroid environments and tyrannosauroid-dominated environments was found to be significantly different, with a higher median number of missing size classes in tyrannosauroid-dominated environments. The analysis provides support for hypotheses, such as intraclade niche partitioning or niche shifting, to explain the differences in the median number of missing size classes between abelisauroid, abelisauroid/megaraptoran, and tyrannosauroid ecosystems and allosauroid/megalosauroid ecosystems. This study implies a complex history regarding the timing of the increase in the median size class for clades that survived the Cretaceous Thermal Maximum, which requires further study.

PMID:41978889 | PMC:PMC13070321 | DOI:10.7717/peerj.21007

PeerJ. 2026 Apr 9;14:e21049. doi: 10.7717/peerj.21049. eCollection 2026.

ABSTRACT

BACKGROUND: Cervical spine pain, particularly among car and motorbike drivers, is a common musculoskeletal issue due to prolonged static postures and repetitive neck movements. This study investigates the prevalence and correlation between cervical spine pain and mobility in car and motorbike drivers.

METHODS: In this cross-sectional study, conducted at Integral Hospital and Research Centre, India, 100 participants (50 car drivers and 50 motorbike drivers) were randomly selected with individuals reporting cervical pain. Participants completed demographic information, driving duration, and cervical pain severity and underwent cervical mobility assessments using smartphone-based tools. Statistical analysis was conducted using independent t-tests and Pearson’s correlation with 95% confidence intervals and Cohen’s d effect sizes, at a significance level of p ≤ 0.05.

RESULTS: Car drivers (mean age 39.2, driving experience 15.6 years, 70% male) and motorbike drivers (mean age 34.8, experience 12.4 years, 80% male) were studied. Motorbike drivers reported higher cervical pain on visual analogue scale (VAS) 5 compared to car drivers VAS 4. Inverse correlations between cervical pain and mobility were noted, with motorbike drivers showing significantly lower cervical mobility across all movements. Negative correlations varied in strength across different movements for both groups, generally more substantial for car drivers.

CONCLUSION: This study highlights the association between cervical pain and reduced mobility among drivers, particularly motorbike drivers. Although causality cannot be determined, the findings support ergonomic interventions and driver education to promote better postures and musculoskeletal health.

PMID:41978888 | PMC:PMC13070313 | DOI:10.7717/peerj.21049

PeerJ. 2026 Apr 9;14:e21080. doi: 10.7717/peerj.21080. eCollection 2026.

ABSTRACT

PURPOSE: To investigate the correlation between sperm DNA fragmentation rate and different types of spontaneous miscarriage after In Vitro Fertilization and Embryo Transfer (IVF-ET).

METHODS: A retrospective analysis was conducted on clinical data from 2,128 patients undergoing in vitro fertilization-embryo transfer treatment at the Reproductive Center of Qingdao Women and Children’s Hospital. Patients were categorized into groups based on pregnancy outcomes and types of spontaneous miscarriage, including an ongoing pregnancy group, biochemical pregnancy group, spontaneous miscarriage group (unknown cause), and spontaneous miscarriage group (embryonic chromosomal abnormality). Differences in the sperm DNA fragmentation index (DFI) among these groups were analyzed and DFI was assessed using the Sperm DNA Fragmentation Detection Kit. Adjustment for confounding factors was performed using multivariable regression analysis and propensity score matching.

RESULTS: Univariate analysis revealed that the DFI in the spontaneous miscarriage group (unknown cause) was higher than that in the ongoing pregnancy group (P = 0.006). Multivariable analysis indicated that sperm DFI (odds ratio (OR) 1.011, 95% confidence interval (CI) [1.001-1.021]) was independently associated with spontaneous miscarriage (unknown cause). Propensity score matching analysis demonstrated that even after predefined conditional matching, the DFI in the spontaneous miscarriage group (unknown cause) remained higher than that in the ongoing pregnancy group (P = 0.042). However, receiver operating characteristic (ROC) curve analysis showed that DFI was a poor discriminator for unexplained miscarriage, with an area under the curve of just 0.556 (95% CI [0.516-0.596]), which is only marginally better than chance.

CONCLUSION: Sperm DFI shows a statistical association with IVF-ET spontaneous miscarriage of unknown cause, but its discriminatory capacity is negligible and it is not a clinically useful predictor. Sperm DFI showed no significant association with biochemical pregnancy or spontaneous miscarriage with embryonic chromosomal abnormality.

PMID:41978881 | PMC:PMC13070320 | DOI:10.7717/peerj.21080

Maedica (Bucur). 2026 Mar;21(1):48-56. doi: 10.26574/maedica.2026.21.1.48.

ABSTRACT

INTRODUCTION: Type 2 diabetes mellitus (T2DM) is a rapidly growing public health challenge in India, driven by urbanization, lifestyle transitions and increasing obesity. Early identification of associated cardiometabolic risk factors is essential to reduce complications and improve disease outcomes.

OBJECTIVES: To assess the prevalence of diabetes and prediabetes and to evaluate associated clinical and socioeconomic risk factors among patients attending a tertiary care center in North India.

METHODS: This cross-sectional study included 696 participants who were evaluated for glycemic status, anthropometric measurements, blood pressure and comorbidities. Diabetes and prediabetes were classified according to standard guidelines. Obesity was defined using Asian-specific body mass index (BMI) cut-offs and hypertension was categorized based on established criteria. Sociodemographic and clinical data were collected using structured questionnaires. Statistical analysis was performed using appropriate comparative tests, with p<0.05 being considered statistically significant.

RESULTS: Among the study population, 89.08% of subjects had diabetes and 10.92% prediabetes. Overweight and obesity were observed in 31.88% and 19.34% of participants, respectively. Hypertension was highly prevalent, with 34.52% of subjects being classified as Stage 2 and 17.96% Stage 1 hypertension. A positive family history was reported in 23.85% of cases. Most patients had a disease duration of less than five years (56.32%). The clustering of obesity, hypertension and diabetes indicated a significant cardiometabolic overlap.

CONCLUSION: The study highlights a substantial burden of diabetes and its associated modifiable risk factors in a North Indian population. Strengthening early detection strategies, lifestyle modification programs and integrated management approaches is essential to reduce long-term complications and improve public health outcomes.

PMID:41978873 | PMC:PMC13061431 | DOI:10.26574/maedica.2026.21.1.48

Maedica (Bucur). 2026 Mar;21(1):12-20. doi: 10.26574/maedica.2026.21.1.12.

ABSTRACT

OBJECTIVES: Postoperative pain following breast surgery remains a significant clinical challenge and may delay recovery while increasing the need for systemic analgesics. Dexmedetomidine, a selective α-2 adrenergic receptor agonist, has been shown to enhance the analgesic effects of local anesthetics. This randomized comparative study aimed to evaluate the analgesic efficacy of dexmedetomidine administered alone or in combination with ropivacaine in patients undergoing modified radical mastectomy.

MATERIALS AND METHODS: This prospective randomized trial was conducted in Hippokrateio Hospital of Athens, Greece, between October 2021 and September 2022, in the first Propaedeutic Surgical Clinic, National and Kapodistrian University of Athens. Ninety female patients (Angle Side Angle – ASA I-II) aged 25-65 years old, who had been scheduled for modified radical mastectomy, were randomized into three groups (n = 30 each). Group R received 0.375% ropivacaine, Group D, dexmedetomidine (1 μg/kg) and Group RD, a combination of both agents. A standardized volume of 10 mL was infiltrated using a landmark-guided technique along the anatomical course of the long thoracic nerve and the adjacent peri-incisional fascial plane before wound closure. Postoperative pain was evaluated using the visual analog scale (VAS) at 0, 4, 8, 16, and 24 hours and only at rest measured in our study. Rescue analgesia with intravenous paracetamol and tramadol was recorded. Statistical analysis included one-way and repeated-measures ANOVA, with significance set at p < 0.05.

RESULTS: The RD group demonstrated clinically meaningful threshold VAS scores at all-time points (p < 0.001) and required substantially less rescue analgesia than Groups R and D, confirming the additive analgesic effect of dexmedetomidine when combined with ropivacaine.

CONCLUSIONS: The combination of dexmedetomidine and ropivacaine significantly improves postoperative analgesia following modified radical mastectomy without increasing adverse effects. Dexmedetomidine appears to be a safe and effective adjuvant within multimodal analgesia strategies.

PMID:41978866 | PMC:PMC13061461 | DOI:10.26574/maedica.2026.21.1.12

Maedica (Bucur). 2026 Mar;21(1):21-26. doi: 10.26574/maedica.2026.21.1.21.

ABSTRACT

Introduction: Continuous positive airway pressure (CPAP) therapy is the main therapeutic method for obstructive sleep apnea syndrome (OSAS). The way of accommodating the patient with the CPAP mask is very important for adherence to therapy. In this study, we tried to determine the patient-reported causes for suboptimal use of CPAP therapy and to draw up some recommendations for their management, with the aim to improve adherence to CPAP therapy. Materials and methods: The present study investigated 86 patients diagnosed with OSAS who were divided into two categories by CPAP adherence (at least four hours per night therapy in at least 70% of the recommended days): CPAP adherent patients (n = 50) and non-adherent patients (n = 36). All participants completed a questionnaire to report the side effects of therapy and the main reasons for suboptimal use of CPAP therapy. Results: The reported causes for the inappropriate use of therapy with statistical significance included side effects of the mask and device, misperception of disease severity and lack of confidence that CPAP therapy is useful for treating OSAS. Dry mouth, the main side effect reported by both adherent and non-adherent patients, was not a predictor of statistical significance for adherence to therapy. Suboptimal use of therapy, a statistically significant factor for adherence to treatment, occurred in some of the OSAS patients who developed anxiety related to CPAP device. Many non-adherent participants used an air humidifier attached to CPAP to treat dry mouth as a side effect, which did not help increase adherence in this group of patients. Conclusion: Multiple factors may be involved in OSAS patients’ adherence to CPAP therapy. Of these, side effects in therapy can play an important role and resolving them can be an essential factor for patient adherence.

PMID:41978863 | PMC:PMC13061430 | DOI:10.26574/maedica.2026.21.1.21