Category: Statistics

Stat Med. 2026 Jan;45(1-2):e70383. doi: 10.1002/sim.70383.

ABSTRACT

Derived variables are variables that are constructed from one or more source variables through established mathematical operations or algorithms. For example, body mass index (BMI) is a derived variable constructed from two source variables: weight and height. When using a derived variable as the outcome in a statistical model, complications arise when some of the source variables have missing values. In this paper, we propose how one can define a single fully integrated Bayesian model to simultaneously impute missing values and sample from the posterior. We compare our proposed method with alternative approaches that rely on multiple imputation (MI), with examples including an analysis to estimate the risk of microcephaly (a derived variable based on sex, gestational age, and head circumference at birth) in newborns exposed to the ZIKA virus.

PMID:41569594 | DOI:10.1002/sim.70383

Nutr Hosp. 2026 Jan 19. doi: 10.20960/nh.05908. Online ahead of print.

ABSTRACT

BACKGROUND: disordered eating behaviors (DEBs) encompass altered eating behaviors that do not meet the diagnostic criteria to be considered eating disorders, yet, like the latter, are associated with multiple medical, psychological, and social complications.

OBJECTIVE: this study aimed to analyze the influence of the internalization of beauty ideals (specifically thinness and muscularity), depressive symptoms, body mass index (BMI), and type of university on DEBs.

METHODS: a correlational, cross-sectional study was conducted with two independent samples of university students from two universities, one public and one private, in Mexico City (n = 1571; 20.8  2.07 years). Data analysis included frequency and percentage estimation, mean comparison, and linear regression analysis.

RESULTS: students enrolled at the private university scored higher for all the variables studied, with statistically significant differences, except for BMI, where public university students scored higher. When compared by BMI, overweight and obese students scored higher for DEBs and internalization. In women, DEBs were predicted by thin-ideal internalization, BMI, and type of university. In male participants, predictors included BMI, depressive symptoms, and type of university.

CONCLUSIONS: the results confirmed previous findings in the literature, with socioeconomic status being a determining factor for the presence of DEBs.

PMID:41569591 | DOI:10.20960/nh.05908

Br J Surg. 2025 Dec 24;113(1):znaf293. doi: 10.1093/bjs/znaf293.

ABSTRACT

BACKGROUND: Health system performance assessment helps identify areas for improvement and guides policy initiatives. Although well-validated indicators exist for measuring organ donation and transplantation performance at the facility level, consensus on indicators for assessing national programmes is lacking. The aim of this study was to develop a comprehensive scorecard for evaluating national organ donation and transplantation programmes.

METHODS: A three-step approach was used. First, a targeted literature review identified potential indicators from regulatory documents, national transplant organization reports, and databases. Second, indicators were mapped to an established transplant system framework and refined through preliminary expert consultations. Third, a modified Delphi consensus process validated the indicators. The Delphi panel comprised international experts in health policy, organ donation, transplantation, and patient representation. Participants rated 168 indicators using a five-point Likert scale across two rounds (24 experts completed round 1 and 22 experts completed round 2). Consensus for inclusion required 80% agreement.

RESULTS: Of 168 indicators evaluated, 103 achieved consensus for inclusion. After consolidation of organ-specific indicators, the final set contained 84 indicators across seven domains: monitoring and reporting (8 indicators), prevention and need (9 indicators), waiting lists (11 indicators), consent (4 indicators), donation (28 indicators), transplantation (14 indicators), and follow-up (10 indicators). The indicator set incorporates established metrics such as waiting list statistics, donation rates, and complication rates alongside novel system-level indicators addressing structural factors, patient-centredness, and equity in care delivery.

CONCLUSION: This validated indicator set provides a standardized tool for assessing and comparing transplant system performance across European countries, supporting performance benchmarking and evidence-informed policy development.

PMID:41569582 | DOI:10.1093/bjs/znaf293

Nutr Hosp. 2026 Jan 21. doi: 10.20960/nh.06109. Online ahead of print.

ABSTRACT

OBJECTIVES: this cross-sectional study investigated the association between the Cardiometabolic Index (CMI) and heart failure (HF) prevalence in hypertensive individuals.

METHODS: this cross-sectional study analyzed dataset from the National Health and Nutrition Examination Survey (NHANES) 2009-2018, focusing on hypertensive adults with complete information on CMI and HF prevalence, employed CMI based on the following formula: [waist circumference (cm)/height (cm)] × [TG (mmol/L)/HDL-C (mmol/L)]. The relationships between CMI and HF prevalence were assessed using weighted multivariable logistic regression and subgroup analysis. Additionally, the threshold effect was determined by applying a two-piece linear regression model.

RESULTS: a total of 3,706 subjects with hypertension were enrolled, with heart failure being reported in 6.77 % of cases. A positive relationship was observed between CMI and HF prevalence. In the fully adjusted model, a one-unit rise in CMI corresponded to a 14 % increased likelihood of HF (OR = 1.14, 95 % CI: 1.03-1.26). Subjects in the top CMI tertile were 49 % more likely to progress to HF than those in the bottom tertile (OR = 1.49, 95 % CI: 1.01-2.21). We did not detect statistically significant interactions across subgroups. An inverted U-shaped correlation was identified between CMI and HF prevalence. The breakpoint was identified at 6.00. On the left of the breakpoint, a positive relationship between CMI and HF prevalence (OR = 1.56, 95 % CI: 1.35-1.79) was observed.

CONCLUSIONS: these findings suggest a positive association between elevated CMI levels and a higher prevalence of HF in hypertensive adults.

PMID:41569581 | DOI:10.20960/nh.06109

JAMA Netw Open. 2026 Jan 2;9(1):e2553518. doi: 10.1001/jamanetworkopen.2025.53518.

ABSTRACT

IMPORTANCE: Unhealthy alcohol use is a leading cause of preventable deaths and is associated with many societal and health problems. Fewer than one-third of people who visit primary care practices in the US are asked about or ever discuss alcohol use with a health professional.

OBJECTIVE: To evaluate the association between primary care practice facilitation and adoption of evidence-based screening and brief counseling for unhealthy alcohol use.

DESIGN, SETTING, AND PARTICIPANTS: The Stop Unhealthy Alcohol Use Now (STUN) single arm, multi-site implementation study was performed at 21 primary care practices across North Carolina between February 1, 2020, and September 1, 2023.

INTERVENTION: Enrolled practices received 12 months of the practice facilitation implementation strategy, including quality improvement coaching, electronic health record support (eg, creating smart phrases or flowsheets, retrieving data), and clinician training on screening and counseling for unhealthy alcohol use.

MAIN OUTCOMES AND MEASURES: Implementation outcomes reflected adoption of evidence-based screening and counseling, including number and percentage of adult patients who were screened for unhealthy alcohol use and who received brief counseling after a positive screening result.

RESULTS: The 21 practices served 54 294 adult patients (mean [SD], 3386.2 [3418.0] per practice). Mean screening rates increased significantly, from 17.4% (95% CI, 6.0%-28.9%) per practice to 57.6% (95% CI, 29.1%-86.1%) by the end of the second quarter of practice facilitation (primary outcome; P < .001). Among screened patients, a weighted 13.9% (95% CI, 6.8%-21.1%) had positive results. The percentage of adult patients with documentation of receiving brief counseling after a positive screening result increased from 0 to 32.3% (95% CI, 13.3%-51.4%) by the end of the second quarter of practice facilitation (P < .001). After month 6, assessment of the implementation outcomes showed sustainment. There was significant variability across participating practices for screening and counseling outcomes.

CONCLUSIONS AND RELEVANCE: The findings of this quality improvement study suggest that practice facilitation was associated with increased adoption of evidence-based screening and counseling for unhealthy alcohol use when provided to small and medium-sized primary care practices. This increase is projected to substantially reduce the harms of unhealthy alcohol use.

PMID:41569565 | DOI:10.1001/jamanetworkopen.2025.53518

JAMA Netw Open. 2026 Jan 2;9(1):e2553530. doi: 10.1001/jamanetworkopen.2025.53530.

ABSTRACT

IMPORTANCE: Nutritional status is a key determinant of child health. While undernutrition and stunting persist among vulnerable populations, overweight and obesity have emerged as growing public health concerns. Quantifying these conditions across subpopulations is essential for guiding interventions.

OBJECTIVE: To describe and compare height-for-age and body mass index (BMI)-for-age adequacy, including the prevalence of overweight, obesity, and stunting, among low-income children in Brazil by region, age, sex, and ethnoracial group.

DESIGN, SETTING, AND PARTICIPANTS: This cohort study used administrative health records of 6 494 753 Brazilian children aged 0 to 10 years who were born between January 1, 2001, and December 31, 2015, and were enrolled in the public primary health care system. Data were obtained from 3 administrative databases-the Unified Registry, Live Birth Information System, and Food and Nutrition Surveillance System-and evaluated at 9 years of age until December 31, 2018. Descriptive statistics were used to summarize baseline characteristics, and prevalence estimates were presented with SEs. Data were analyzed from December 1, 2024, to June 31, 2025.

EXPOSURE: Demographic characteristics (age, sex, and ethnoracial group) and geographic region of residence.

MAIN OUTCOMES AND MEASURES: Anthropometric adequacy was assessed using height-for-age and BMI-for-age z scores, classified according to World Health Organization standards. Outcomes included the prevalence of stunting (height-for-age z scores less than -2), overweight (BMI-for-age z scores greater than 1), and obesity (BMI-for-age z scores greater than 2), reported overall and by subgroups.

RESULTS: Among the 6 494 753 million children, 51.48% were female, with a mean (SD) age of 3.6 (2.8) years. In terms of race and ethnicity, 0.26% were Asian; 3.84%, Black; 0.90%, Indigenous; 61.71%, Parda; and 28.72%, White; 4.57% had missing or inconsistent data. Overall, 433 754 children (6.68%) experienced stunting, 818 967 (12.61%) had overweight, and 489 541 (7.54%) had obesity. Estimated obesity prevalence (SE) at 5 years of age was 8.48% (0.02%), increasing to 10.09% (0.05%) at 9 years of age. Obesity was more frequent boys (14.12% [0.12%]) than girls (10.09% [0.05%]) at 9 years of age. Among girls, obesity prevalence (SE) was 11.8% (0.09%) among those who identified as White, 9.12% (0.06%) among those who identified as Parda, and 7.46% (0.48%) among those who identified as Indigenous.

CONCLUSIONS AND RELEVANCE: This large-scale cohort study highlights persistent regional and ethnoracial disparities in both growth faltering and excess weight gain. The coexistence of undernutrition and obesity in the same population underscores the urgency for targeted nutrition and health policies in early childhood.

PMID:41569564 | DOI:10.1001/jamanetworkopen.2025.53530

JAMA Netw Open. 2026 Jan 2;9(1):e2554972. doi: 10.1001/jamanetworkopen.2025.54972.

ABSTRACT

IMPORTANCE: Since 2012, the Hospital Readmissions Reduction Program (HRRP) has penalized hospitals for excess, risk-adjusted 30 day readmissions among traditional Medicare (TM) beneficiaries. While risk adjustment may address observable differences in patient severity, it cannot account for unobservable differences. Medicare Advantage (MA) enrollment has continued to increase, and MA beneficiaries have been found to be both observably and unobservably healthier than their TM counterparts. Because relatively lower-severity patients are increasingly likely to enroll in MA, hospitals with higher MA penetration may have unobservably higher-severity TM patients, resulting in higher-than-estimated readmission risk and excessive HRRP penalties.

OBJECTIVE: To determine whether unobserved selection, as proxied by MA penetration, could be associated with distorted HRRP penalties and how associations may be moderated by peer grouping, which was incorporated into HRRP’s 2019 revision to penalty calculations.

DESIGN, SETTING, AND PARTICIPANTS: This retrospective cohort study included hospitals serving Medicare beneficiaries from fiscal years 2019 to 2022 for 6 HRRP-targeted conditions, including acute myocardial infarction, chronic obstructive pulmonary disease, heart failure, pneumonia, coronary artery bypass graft surgery, and elective primary total hip or knee arthroplasty. Data were analyzed from January 2024 to October 2025.

EXPOSURE: MA penetration at the hospital-year level.

MAIN OUTCOMES AND MEASURES: Excess readmission ratios (ERRs) and calculated HRRP penalties at the hospital-year level. To test whether HRRP penalties could have been distorted by unobserved selection, the association between the share of hospital admissions for MA patients (MA penetration) and excess readmission ratios (ERRs) for all patients was estimated, controlling for county-level variation and hospital-level covariates. The ERRs were rescaled by MA penetration to account for unobserved selection, and the rescaled ERRs were used to reestimate HRRP penalties under non-peer grouping and peer grouping paradigms.

RESULTS: This study included 3203 hospitals and 12 135 hospital-years. After adjusting for MA penetration, estimates indicated that hospitals in the first quintile of MA penetration would be penalized by a mean (SD) of $30 736 ($24 819.75) more, while hospitals in the fifth quintile would be penalized by a mean (SD) of approximately $26 915 ($42 017.23) less. Peer grouping does not mitigate these penalty distortions. Across hospitals, penalty redistributions would amount to $284 to $297 million annually.

CONCLUSIONS AND RELEVANCE: The findings of this study suggest that including MA penetration explicitly in risk adjustment or in peer group definitions may dampen distortions from unobservable patient severity in HRRP penalty calculations.

PMID:41569562 | DOI:10.1001/jamanetworkopen.2025.54972

Nutr Hosp. 2026 Jan 20. doi: 10.20960/nh.06129. Online ahead of print.

NO ABSTRACT

PMID:41569559 | DOI:10.20960/nh.06129

JAMA. 2026 Jan 22. doi: 10.1001/jama.2025.26179. Online ahead of print.

ABSTRACT

IMPORTANCE: For patients with idiopathic pulmonary fibrosis (IPF), cough impairs quality of life; effective treatments for IPF-associated cough are needed.

OBJECTIVE: To determine if nalbuphine extended release (ER), a κ opioid receptor agonist and μ-opioid receptor antagonist, decreases cough compared with placebo in patients with IPF-associated cough.

DESIGN, SETTING, AND PARTICIPANTS: In this randomized, double-blind, placebo-controlled phase 2b trial conducted at 52 sites in 10 countries, patients with IPF, chronic cough for at least 8 weeks, and a Cough Severity Numerical Rating Scale (0, no cough; 10, worst possible cough) score of 4 or higher were enrolled from February 2024 to February 2025, with last follow-up in April 2025. Statistical analyses were conducted from May to August 2025.

INTERVENTION: Patients were randomized 1:1:1:1 to receive nalbuphine ER at doses of 27 mg, 54 mg, or 108 mg or placebo twice daily for 6 weeks.

MAIN OUTCOMES AND MEASURES: The primary outcome was the relative change from baseline in 24-hour cough frequency (coughs/h), measured with a digital cough monitor, for nalbuphine ER compared with placebo at week 6. The key secondary outcome was the relative change from baseline in the patient-reported cough frequency (Evaluating Respiratory Symptoms in IPF cough subscale; scores range from 0-4, lower scores indicate lesser cough frequency) at week 6.

RESULTS: Of the 223 patients screened, 165 were randomized (42, 43, 40, and 40 to receive nalbuphine ER 27 mg, 54 mg, and 108 mg, and placebo, respectively) and 160 were included in the primary analysis (median age, 71 [range, 51-85] years; 28.5% female). The baseline mean (SD) cough count was 28.3 (27.4) coughs/h. In the nalbuphine ER 27 mg, 54 mg, and 108 mg twice-daily groups, the mean relative decrease in the cough count and the absolute decrease in coughs/h were 47.9% (from 24.6 to 11.9; P = .008), 53.4% (from 28.0 to 14.9; P < .001), and 60.2% (from 31.5 to 11.9; P < .001), respectively, compared with placebo (16.9%; from 29.4 to 28.1 coughs/h). For the key secondary outcome of patient-reported cough frequency at week 6, the relative and absolute changes were -31.4% (from 2.3 to 1.5; P = .14), -40.6% (from 2.6 to 1.4; P = .004), and -40.2% (from 2.4 to 1.4; P < .005) in the 27-mg, 54-mg, and 108-mg groups, respectively, compared with -21.9% (from 2.6 to 1.9) with placebo.

CONCLUSIONS AND RELEVANCE: For patients with IPF-associated chronic cough, all 3 doses of nalbuphine ER reduced objective cough frequency and the 2 higher doses improved patient-reported cough frequency at 6 weeks.

TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT05964335.

PMID:41569557 | DOI:10.1001/jama.2025.26179

Psychol Trauma. 2026 Jan 22. doi: 10.1037/tra0002102. Online ahead of print.

ABSTRACT

OBJECTIVE: Research demonstrates that oppression can produce symptoms consistent with posttraumatic stress disorder (PTSD), but traditional trauma assessments do not account for the impacts of oppression. This study addressed this gap by establishing the dimensionality, measurement equivalence, reliability, and convergent validity of the Oppression-Based Traumatic Stress Inventory across two samples.

METHOD: The samples comprise PTSD treatment study clients (Sample 1; n = 129) and Hispanic-serving institution undergraduate students (Sample 2; n = 227) who completed a series of questionnaires, including the Oppression-Based Traumatic Stress Inventory.

RESULTS: Confirmatory item factor analyses for the 25 ordinal Oppression-Based Traumatic Stress Inventory items were conducted for each sample. Model fit was unsatisfactory for two initial four-factor solutions: one based on the Diagnostic and Statistical Manual of Mental Disorders, fifth edition, PTSD symptom clusters and another based on exploratory factor analyses on a previous sample. Given the very high correlations among the factors, however, we refined the structure into three new factors (oppression-related distress and avoidance, fear and blame of others, and general depression and anxiety symptoms) that yielded acceptable fit after adding four error covariances. Measurement invariance testing revealed three of the 25 items had parameters that differed across samples. Excellent reliability was found for all three factors. A higher order factor appeared plausible but was largely noninvariant across samples. Finally, we provide evidence for convergent validity (with measures of standard PTSD, posttraumatic cognitions, depressive symptoms, psychosocial functioning, racial discrimination, gender discrimination, and, to some degree, material hardship).

CONCLUSIONS: Our findings strengthen the psychometric evidence supporting this novel measure of oppression-based traumatic stress, an important step in furthering intersectional research on this topic. (PsycInfo Database Record (c) 2026 APA, all rights reserved).

PMID:41569537 | DOI:10.1037/tra0002102