Linear Mixed Model Analysis Research Articles

Effects of psychosocial characteristics on cognitive function in middle-aged and older adults: Focusing on change by year using the Korean Longitudinal Study of Aging panel data (2014-2018).

Old age is associated with a higher risk of dementia. Psychosocial characteristics frequently affect cognitive function; however, the exact mechanism underlying the effect of psychosocial factors on cognitive function is unclear. Therefore, this study aimed to investigate the effects of psychosocial characteristics on cognitive function. The participants comprised 4809 middle-aged and older (years 50+) adults. The analysis used data from the Korean Longitudinal Study of Aging from 2014 to 2018. The effects of neighborhood interaction, depression, life satisfaction, and economic activity on cognitive function were examined, and a linear mixed model analysis was performed to assess the change in cognitive function by year. A statistically significant association was found between neighborhood interaction and time. Additionally, cognitive function decreased in the presence of depression and with time. In men, significant interactions were found between depression and time and between economic activity and time. In women, significant interactions were found between life satisfaction and time. The findings indicate that since active neighborhood interaction positively affects cognitive function, it is necessary to develop various community-wide social activity programs for middle-aged and older adults. As depression is a risk factor for cognitive impairment, it is crucial to prevent cognitive decline through continuous management of depression. Given the positive effects of economic activity on cognitive function in men, it is essential to expand infrastructure to sustain economic activity by developing educational programs and creating job opportunities for middle-aged and older men.

Intentional Imperfection Program: A pilot randomised controlled trial to help university students manage perfectionism

Given that perfectionism has been associated with interpersonal, academic, and mental health difficulties in university students, helping them manage their perfectionism is crucial. This pilot trial examined the feasibility, acceptability, and potential efficacy of an online perfectionism program designed to target the mechanisms that link perfectionism to psychological distress. Seventy first-year psychology students from Macquarie University with high levels of perfectionism were recruited into this two-arm pilot trial and randomised to either the intervention (i.e., perfectionism program) or attention placebo control (i.e., lifestyle program) condition. We assessed indicators of feasibility and acceptability, as well as measures related to perfectionism, psychological distress, emotion regulation skills, interpersonal and academic functioning at baseline, one-month post treatment, and three-month follow-up (blinded outcome assessment). Our analyses revealed that, while participants expressed overall satisfaction with the program, there was low engagement with it (Mcompletion rate=36.23%), and retention in the study was low (response rates for post-treatment: 65.71% and follow-up: 48.57%). Bearing this in mind, our linear mixed model analyses revealed greater reductions in perfectionistic traits and cognitions, interpersonal hostility, and loneliness, as well as increases in self-compassion in the intervention group compared to the control group at post-treatment and/or follow-up. However, we did not observe statistically significant changes in other important treatment outcomes (e.g.,psychological distress). Given these findings, adjustments to improve engagement and retention should occur before proceeding with a larger, definitive trial. This trial was retrospectively registered on the Australian and New Zealand Clinical Trials Registry (no. ACTRN12622000960752).

Playing surface and sport contact status modulate time to lower extremity musculoskeletal injury at a greater level than concussion history among collegiate student-athletes

ObjectivesWhile previous investigations have demonstrated a positive correlation between previous concussion and risk of subsequent lower extremity musculoskeletal injury (LEMSKI), the effect of sport- and patient-specific factors on time to injury has not been thoroughly described. This study's main objective was to evaluate the relationship between prior concussion and time to LEMSKI among a population of collegiate student-athletes. Secondary objectives were to evaluate the relationship between playing surface, sport contact status, and biologic sex on time to LEMSKI. We hypothesized that those with previous concussions, those competing on synthetic surfaces, and those competing in collision sports would experience decreased latency to LEMSKI overall. MethodsA retrospective observational analysis of National Collegiate Athletic Association (NCAA) Division I student-athletes was conducted utilizing a mixed linear model analysis with contrasts. Inclusion criteria included participation in the Pac-12 Health Analytics Program with a documented LEMSKI between 2017 and 2020. Exclusion criteria included concurrent concussion and LEMSKI, injury resulting in serious morbidity or mortality, and incomplete medical record. Participants were classified by whether they sustained a concussion prior to LEMSKI in each athletic season. ResultsOf 1179 athletes included, 1140 had no previous concussion and 37 had a previous concussion. There was no observed effect of previous concussion (F ​= ​0.038; p ​= ​0.846) on time to LEMSKI overall. Student-athletes competing on constructed surfaces sustained a subsequent LEMSKI 14.5 days sooner (SE ​= ​5.255; p ​= ​0.045), and those competing on organic surfaces sustained a subsequent LEMSKI 23.5 days sooner (SE ​= ​4.018; p ​< ​0.001) in the season than those competing on synthetic surfaces. Contact sport student-athletes sustained a subsequent LEMSKI 52.1 days sooner than collision sport student-athletes (SE ​= ​5.248; p ​< ​0.001), and limited contact sport student-athletes sustained a subsequent LEMSKI 42.29 days sooner than collision sport student-athletes (SE ​= ​4.463; p ​< ​0.001). There was no observed effect of biologic sex (F ​= ​0.602; p ​= ​0.438) on time to LEMSKI overall. ConclusionThere was no observed impact of concussion on time on LEMSKI overall in this collegiate athletic population. Contact sports were associated with decreased time to LEMSK, while synthetic surfaces were associated with increased time to LEMSKI in this population. There was no observed impact of biologic sex on time to LEMSKI. Level of evidenceCase-control, level of evidence III.

Vitamin K2 Supplementation in Hospitalised COVID-19 Patients: A Randomised Controlled Trial.

Background: In observational studies, high levels of desphospho-uncarboxylated matrix gla protein (dp-ucMGP) that result from vitamin K deficiency were consistently associated with poor clinical outcomes during COVID-19. Vitamin K-activated matrix gla protein (MGP) is required to protect against elastic fibre degradation, and a deficiency may contribute to pathology. However, intervention trials assessing the effects of vitamin K supplementation in COVID-19 are lacking. Methods: This is a single-centre, phase 2, double-blind, randomised, placebo-controlled trial investigating the effects of vitamin K2 supplementation in 40 hospitalised COVID-19 patients requiring supplemental oxygen. Individuals were randomly assigned in a 1:1 ratio to receive 999 mcg of vitamin K2-menaquinone-7 (MK-7)-or a placebo daily until discharge or for a maximum of 14 days. Dp-ucMGP, the rate of elastic fibre degradation quantified by desmosine, and hepatic vitamin K status quantified by PIVKA-II were measured. Grade 3 and 4 adverse events were collected daily. As an exploratory objective, circulating vitamin K2 levels were measured. Results: Vitamin K2 was well tolerated and did not increase the number of adverse events. A linear mixed model analysis showed that dp-ucMGP and PIVKA-II decreased significantly in subjects that received supplementation compared to the controls (p = 0.008 and p = 0.0017, respectively), reflecting improved vitamin K status. The decrease in dp-ucMGP correlated with higher plasma MK-7 levels (p = 0.015). No significant effect on desmosine was found (p = 0.545). Conclusions: These results demonstrate that vitamin K2 supplementation during COVID-19 is safe and decreases dp-ucMGP. However, the current dose of vitamin K2 failed to show a protective effect against elastic fibre degradation.

Course of growth and nutritional status in Swiss children with food allergies

Summary Purpose Studies suggest that children with immunoglobulin E (IgE)-mediated food allergies (FA) are at risk of impaired growth, especially those with cow’s milk or multiple FA. However, there is limited long-term data available on this topic. This analysis presents the growth of Swiss children for the first year after FA diagnosis. Methods This is a secondary analysis of data from a multicentered study following food allergic children (0–10 years) over 1 year post diagnosis, comparing those who received dietary counselling with those who did not. Growth z‑scores were calculated based on World Health Organization (WHO) standards, using data reported by caregivers. To analyze data, linear mixed models with between-subject factors related to dietary counselling, number of FA, and cow’s milk allergy were fitted to the data. Results In the 48 children (median age 16 months) studied, we observed an increasing prevalence of wasting (weight-for-length/height z‑score &lt; 2; 2–10%) and a lower prevalence of stunting (length/height-for-age &lt; 2; 0–2%) over the 1‑year period. Twelve months after diagnosis, all median z‑scores showed an increase. Linear mixed model analysis did not find any significant within-subject and between-subject effects on growth. Conclusion Children with IgE-mediated FA can have normal growth if children with cow’s milk allergy or multiple food allergies receive dietary counselling. Routine length/height and weight measurements should be taken to identify individual malnutrition and to initiate tailored nutritional interventions. Larger studies with longer duration are needed to assess further growth development in children with IgE-mediated food allergies.

Comparison of Patients Operated for Lumbar Spinal Stenosis With and Without Spondylolisthesis​​​​​: A Secondary Analysis of the NORDSTEN Trials.

Observational cohort study (secondary analysis of two randomized trials). The aim of this study was to investigate whether function, disability, pain, and quality of life before surgery and patient-reported outcome as well as complication and reoperation rates up to 2 years after surgery differ between lumbar spinal stenosis patients with and without spondylolisthesis. Lumbar spinal stenosis is a degenerative condition of the spine, which appears with or without degenerative spondylolisthesis often presenting similar signs and symptoms. This study is a secondary analysis of two randomized trials on patients with lumbar spinal stenosis with and without spondylolisthesis conducted at 16 public Norwegian hospitals. Disability, function, back pain, leg pain, quality of life, complication, and reoperation rates up to 2 years after surgery were compared between the two cohorts. A total of 704 patients were included in this study, 267 patients with spondylolisthesis [median age: 67.0 yr (IQR: 61.0-72.0 yr); 68.7% female] and 437 patients without spondylolisthesis [median age: 68.0 yr (IQR: 62.0-73.0 yr); 52.9% female]. In the linear mixed-model analysis there were no significant differences in disability, function, back pain, leg pain, and quality of life scores between the two cohorts of patient with and without spondylolisthesis before surgery or at 2 years of follow-up. The complication rate was 22.9% in patients with spondylolisthesis and 12.1% in patients without spondylolisthesis ( P <0.001). There were no significant differences in reoperation rates. In patients with lumbar spinal stenosis the symptom burden before surgery and the clinical outcome up to 2 years after surgery were similar independently of a concomitant spondylolisthesis. II.

Impact of visual impairment on physical function, activities of daily living, and length of hospital stay in patients with Phase I cardiac rehabilitation: A cohort study

The number of patients with visual impairment (VI) is increasing rapidly around the world, and its negative effects are becoming a problem. There is a strong relationship between VI and cardiovascular disease, and patients with cardiovascular disease have a higher prevalence of VI. The aim of this study was to examine the effects of VI on physical function, activities of daily living, and length of hospital stay in Phase I cardiac rehabilitation (CR) patients. This prospective multicenter cohort study included patients who underwent Phase 1 CR from October 2020 to March 2023 at four affiliated Regional Medical Care Support Hospitals in Japan. VI was assessed by a self-reported questionnaire. Linear mixed model analysis was performed to evaluate the association between VI and walking speed, short physical performance battery (SPPB), functional independence measure (FIM), and length of hospital stay, respectively. Of the 3608 patients with a hospital stay of at least 5 days and who underwent Phase 1 CR, 565 were included in this study. VI was reported by 23.9%. The VI group had slower walking speed (0.89 vs. 1.01 m/s, p &lt; .001), lower SPPB (11.0 vs. 12.0 points, p &lt; .001), and lower FIM (122.0 vs. 125.0 points, p &lt; .001) than the non-VI group. There was no significant difference in length of hospital stay between the two groups. Multivariate linear regression analysis adjusted for confounding factors showed that VI was significantly associated with walking speed ( p = .030) and length of hospital stay ( p = .017), whereas VI was not associated with SPPB and FIM. This study revealed Phase 1 CR patients with VI decreased walking speed, which corresponds to sarcopenia. Furthermore, VI was independently associated with walking speed and length of hospital stay in Phase 1 CR patients.

Persian compounds in the mental lexicon

Compound words exhibit properties of both single words and phrases, raising the question of the extent to which compounds are processed as single units or as word combinations. Most studies have addressed this in Germanic languages (English, German and Dutch) which have the similar compound structure of modifier-head ordering. To see whether this limits our understanding of compound word processing and to examine compound decomposition in another language, we presented Persian stimuli auditorily in a paradigm involving typing out stimuli. We examined the effects of semantic transparency, modifier-head ordering and the potential differences between attached compounds written without spaces and those with a space between the constituents. We report the inter-keystroke-interval times, yielding letter-by-letter production of compound structures produced by 31 native speakers of Persian. Results analyzed in a linear mixed-model regression analysis suggested that, for all compounds, typing speed is slowed at the boundary between the constituents of Persian compound words. These effects, which we interpret to be evidence of morphological decomposition, were present for both semantically transparent and opaque compounds, for both head-initial and head-final compounds, and for both attached and spaced compounds. We observed greater morphological decomposition effects in semantically transparent (versus opaque) compounds. We also observed that the way transparency influences the degree of decomposition is moderated by headedness. Thus, this first report for the written production of compound words confirms previous observations of significant decomposition at morphological boundaries in English compounds, but with variation specific to Persian.

Investigating the Effects of Discrimination Experiences on Everyday Metamemory Accuracy.

Lifetime and daily experiences of discrimination contribute to impaired performance on cognitive assessments. However, the underlying mechanism by which discrimination negatively affects cognition is unclear. Recent research investigating stress-induced impairment of metamemory may address the relationship between discrimination experiences and cognitive impairment. The aim of this study was to determine the relationship of lifetime and daily experiences of discrimination, daily affect balance, baseline objective cognitive performance, and sociodemographic variables (age, race, ethnicity, and sex) with metamemory accuracy across the lifespan (ages 20-75). Impaired metamemory accuracy was defined by the number of subjective cognitive complaints. Diary data from the Midlife in the United States (MIDUS Refresher 1) Daily Diary Project (N = 782) was used for these analyses. Results from linear mixed model analyses showed significant within-person effects of daily discrimination, where people who reported more daily discrimination also reported lower metamemory accuracy, and daily affect balance, where people who reported very negative affect also reported lower metamemory accuracy. Additionally, linear mixed model analyses revealed significant between-person effects of race on metamemory accuracy, with individuals from minoritized racial groups generally reporting poorer metamemory accuracy. Daily discrimination experiences also interacted with other variables in predicting day-to-day metamemory accuracy. These findings add to our understanding of how psychosocial stress in the form of daily discrimination experiences may impair metamemory processes contributing to increased subjective cognitive complaints. Future research should consider the contribution of daily experiences of discrimination across the lifespan to poor cognitive outcomes in later life.

Association of urinary cadmium levels with peripheral leukocyte classification counts among middle-aged and older adults aged 40-89 in selected areas of China

Objective: To investigate the association of urinary cadmium levels with peripheral leukocyte classification counts among middle-aged and older adults aged 40 to 89 years in selected areas of China. Methods: The research was based on the survey of the impact of soil quality of agricultural land on human health in typical areas conducted in 2019-2020. A total of 5 600 middle-aged and older adults aged 40 to 89 years were included by using a multi-stage stratified random sampling method. Baseline characteristics of the subjects were collected and physical examinations were performed. Random midstream urine was collected to measure urinary cadmium and urinary creatinine and fasting venous blood was collected to measure the leukocyte count, neutrophil count, lymphocyte count, monocyte count and eosinophil count. The linear mixed effect model was used to analyse the association of urinary cadmium levels with leukocyte classification counts, and the dose-response relationship between them was analyzed by using the restricted cubic spline (RCS) function. Results: The age of the subjects was (63.17±12.02) years; 2 851 (50.91%) were males; and the M (Q1, Q3) of urinary creatinine-corrected urinary cadmium levels was 2.69 (1.52, 4.69) μg/g·creatinine. After adjusting for confounding factors, the results of linear mixed effects model analysis showed that for each 1-unit increase in urinary creatinine-corrected urinary cadmium level, the percentage change [% (95%CI)] of leukocyte count and lymphocyte count was -1.70% (-2.61%, -0.79%) and -1.57% (-2.86%, -0.26%), respectively. RCS function showed a negative linear relationship between urinary creatinine-corrected urinary cadmium levels and leukocyte counts and lymphocyte counts, respectively (all Pnon-linear>0.05). Conclusion: Urinary cadmium levels are negatively associated with leukocyte count and lymphocyte count among middle-aged and older adults aged 40 to 89 years in selected areas of China.

Increase in choroidal thickness after blue light stimulation of the blind spot in young adults.

Blue light activates melanopsin, a photopigment that is expressed in intrinsically photosensitive retinal ganglion cells (ipRGCs). The axons of ipRGCs converge on the optic disc, which corresponds to the physiological blind spot in the visual field. Thus, a blue light stimulus aligned with the blind spot captures the ipRGCs axons at the optic disc. This study examined the potential changes in choroidal thickness and axial length associated with blue light stimulation of melanopsin-expressing ipRGCs at the blind spot. It was hypothesized that blue light stimulation at the blind spot in adults increases choroidal thickness. The blind spots of both eyes of 10 emmetropes and 10 myopes, with a mean age of 28 ± 6 years (SD), were stimulated locally for 1-minute with blue flickering light with a 460nm peak wavelength. Measurements of choroidal thickness and axial length were collected from the left eye before stimulation and over a 60-minute poststimulation period. At a similar time of day, choroidal thickness and axial length were measured under sham control condition in all participants, while a subset of 3 emmetropes and 3 myopes were measured after 1-minute of red flickering light stimulation of the blind spot with a peak wavelength of 620nm. Linear mixed model analyses were performed to examine the light-induced changes in choroidal thickness and axial length over time and between refractive groups. Compared with sham control (2 ± 1μm, n = 20) and red light (-1 ± 2μm, n = 6) stimulation, subfoveal choroidal thickness increased within 60min after blue light stimulation of the blind spot (7 ± 1μm, n = 20; main effect of light, p < 0.001). Significant choroidal thickening after blue light stimulation occurred in emmetropes (10 ± 2μm, p < 0.001) but not in myopes (4 ± 2μm, p > 0.05). Choroidal thickening after blue light stimulation was greater in the fovea, diminishing in the parafoveal and perifoveal regions. There was no significant main effect of light, or light by refractive error interaction on the axial length after blind spot stimulation. These findings demonstrate that stimulating melanopsin-expressing axons of ipRGCs at the blind spot with blue light increases choroidal thickness in young adults. This has potential implications for regulating eye growth.

Toddlers’ Cortisol Levels in Childcare and at Home

ABSTRACT Research Findings: Measuring toddlers’ cortisol levels both in childcare and at home and their relation to child- and childcare-related factors may help to identify stress-inducing childcare practices and children who are more vulnerable to stress in childcare. Accordingly, toddlers’ (n = 320, 51.2% female, mean age = 26.8 months) cortisol levels in childcare and at home and their relation to childcare quality and child- and family-related factors were investigated using linear mixed model analyses. Mid-morning to mid-afternoon cortisol levels increased in childcare and decreased at home. Younger children had higher overall cortisol levels. Children attending groups with a higher caregiver – child ratio had slightly higher cortisol levels in childcare and slightly lower cortisol levels at home. Toddlers attending disorganized groups were considerably more stressed in childcare. Practice or Policy: The present study underlines the importance of sufficient caregiver availability and stable routines in toddler classrooms.

The Comparison of Individual and Group Hybrid Telerehabilitation Methods in Women with Urinary Incontinence.

The aim is to compare the effects of the progressive training program (PTP), a new protocol, with two different hybrid telerehabilitation methods, on the parameters related to urinary incontinence in women with urinary incontinence. A total of 50 participants with stress or mixed urinary incontinence participated in this two-arm, parallel-group, randomized, non-inferiority trial. Individual hybrid training (IHT) or group hybrid training (GHT) was given to women for 8weeks. The Power, Endurance, Repetitions, Fast contractions, and Every Contraction Timed (PERFECT) scheme and surface electromyography were used to assess pelvic floor muscle function, whereas quality of life, exercise adherence, and symptoms were assessed by questionnaires and a 3-day bladder diary. An intention-to-treat analysis was performed. Linear mixed model analysis with the factors "time" and "group" was used to determine the effects of IHT and GHT. The primary outcome was changes in pelvic floor muscle function as evaluated using the PERFECT scheme and surface electromyography at the 4th and 8th weeks relative to baseline. No statistical difference was found between the groups except for "power" of the PERFECT scheme and "nocturnal urination frequency" (p > 0.05). The GHT showed significant improvement in P and nocturnal urination frequency at the end of the 8th week (p < 0.05). From baseline to week 8, the effect size for the P value was found to be small (Cohen's d = 0.33). Eightweeks of PTP did not lead to different results in incontinence-related parameters in either of the training methods. It may be better to conduct GHT in terms of implementing PTP in incontinence and training programs in terms of time, staff workload, and applicability.

Physical activity and dexamethasone for cancer related fatigue: A preliminary placebo controlled randomized control trial.

12050 Background: Despite high frequency and significant impact on quality of life, there are limited treatment options available for cancer related fatigue (CRF) in patients with advanced cancer. The primary aim of the study was to determine the feasibility (adherence, safety, and satisfaction) of the combination therapy, physical activity (PA) plus Dexamethasone (Dex); and PA plus placebo (Pl) for CRF. The secondary aim was to explore the effects of PA+Dex, and PA+Pl on CRF as assessed by Functional Assessment of Cancer Illness Therapy–fatigue (FACIT-F). Methods: In this phase 2, randomized, double blind, placebo controlled trial, patients with advanced cancer with CRF ≥ 4/10 on Edmonton Symptom Assessment Scale were eligible. Patients were randomized to standardized PA for 4 weeks plus either 4mg of Dex (PA+Dex arm), or Pl (PA+PL arm) BID for the first 7 days. Changes in FACIT-F scores from baseline to Day 8, and Day 29 were assessed. Other outcomes included change in quality-of-life scores. Results: A total of64 (89%) patients were evaluable. The median (IQR) changes in FACIT-F scores at Day 8 and Day 29 from baseline were 9 (2,16), P&lt; 0.001; 5.75 (0,12.5), P=0.015 for PA+ Dex arm, and 3.5 (-2.13, 10), P=0.054; 6.50 (2.5, 15.5), P=0.006 for PA+ Pl arm respectively. Exploratory Linear Mixed Model (LMM) analysis showed significant treatment effect of PA +Dex, with treatment having improvement of 5.63 units for FACIT-F scores (95% Cl 1.74,9.52), P=0.005. Effect sizes for improvement of FACIT-F scores at Day 8 and Day 29 were -3.49, -2.43 in PA+Dex arm; and -1.93, -2.72 in PA+Pl arm, respectively. Effect sizes for change in fatigue related symptoms and quality of life scores as assessed by Patient-Reported Outcome Measurement Information System-Fatigue T-scores, Multidimensional Fatigue Symptom Inventory-Short Form total, and Functional Assessment of Cancer Therapy -General scores at Day 8, and Day 29 in PA+ Dex arm were 2.93 (P=0.005), 2.82 (P=0.005); 2.27 (P=0.023), 2.68 (P=0.007); -2.39 (P=0.017), -3.26 (P=0.001) respectively. Adherence to Dex and Pl were 91% and 92%, respectively, Satisfaction rates with PA+Dex and PA+Pl arms were 98% and 79%, respectively. There was no significant difference in grade ≥3 adverse events between the two arms (P = 0.36). Conclusions: Satisfaction, and tolerability to the combination therapy, and medication adherence was excellent.PA + Dex significantly improved CRF at day 8 and 29. The improvement was sustained 3 weeks after discontinuation of Dex. Further larger studies are justified. Clinical trial information: NCT03583255 .

Do trait-assessed valenced emotion motives predict valenced affective states in the daily lives of university students?

Although emotion motives have been proposed to predict momentary valenced affect experienced in everyday life, little research has been conducted on this issue. The present study examined whether trait-level hedonic and contra-hedonic emotion motives would significantly predict daily hedonic and contra-hedonic emotion goals and subsequent daily affective states. A sample of 268 university students self-reported levels of trait emotion motives in a single-occasion survey, followed by a 14-day daily diary study which assessed momentary emotion goals and affective mood states. Linear mixed model analyses showed that trait hedonic emotion motives (trying to experience positive emotions) significantly predicted corresponding daily hedonic emotion goals and subsequent higher levels of daily positive affect, while trait contra-hedonic motives (trying to experience negative emotions) evidenced an analogous pattern resulting in higher levels of daily negative affect. These findings support a bivariate rather than a bipolar relationship between hedonic and contra-hedonic motives.

Navigating the American Board of Surgery In-Training Examination (ABSITE) Success: Insights From Pre-assessment Practices in Preparing Surgical Residents for Competitive Sub-specialties.

Introduction The American Board of Surgery In-Training Examination (ABSITE) is a critical tool in assessing surgical residents' readiness for board certification and clinical practice. While various factors influencing ABSITE performance have been examined, the impact of innovative educational resources, such as TrueLearn, remains underexplored. TrueLearn's adaptive learning algorithms and comprehensive question banks offer a promising adjunct to traditional study methods. This study investigates the relationship between TrueLearn utilization and ABSITE performance among general surgery residents. Methods This retrospective study, ethically approved by the Marshall University Institutional Review Board (IRB No. 2097669-1), analyzed the performance of general surgery residents at Marshall University from 2014 to 2022. Data were collected on ABSITE scores. Additionally, quiz percentages (Quiz %) and scores from two mock exams (Exam 1 and Exam 2), all provided by the TrueLearn platform, were included in the analysis. Descriptive statistics summarized the sample characteristics. Linear mixed models were employed to examine the associations between TrueLearn engagement and ABSITE performance, accounting for the correlated nature of the data and addressing any missing data at random. Statistical analyses were conducted using the Statistical Analysis System (SAS, version 9.4; SAS Institute Inc., Cary, NC), with significance defined as a p-value < 0.05. Results The study cohort included 58 residents from 2016 to 2022. Linear mixed model analysis revealed significant positive correlations between TrueLearn Quiz %, Exam 1 scores, and Exam 2 scores with ABSITE performance. A 1% increase in Quiz % was associated with a 0.77-point rise in ABSITE scores (95% CI: 0.65, 0.89; p < 0.0001). For Exam 1, each point increase corresponded to a 6.36-point increase in ABSITE scores (95% CI: 5.01, 7.7; p < 0.0001), while Exam 2 scores showed a 3.8-point increase per point (95% CI: 2.74, 4.86; p < 0.0001). Discussion and conclusion Our findings underscore the significant impact of TrueLearn engagement on ABSITE performance, with higher quiz percentages and mock exam scores predictive of better ABSITE outcomes. This suggests that regular use of TrueLearn's educational resources enhances residents' knowledge and exam readiness. These results advocate for the integration of innovative educational tools such as TrueLearn into surgical training programs to optimize study strategies and improve exam performance. However, the study's retrospective design and single-institution focus limit the generalizability of the findings. Future research should explore these relationships in diverse settings and specialties and consider additional factors influencing ABSITE performance. This study highlights the positive association between TrueLearn utilization and ABSITE performance among general surgery residents, emphasizing the importance of innovative educational resources in surgical training. By enhancing engagement with platforms such as TrueLearn, surgical programs can improve residents' readiness for high-stakes examinations, ultimately contributing to the development of proficient surgical practitioners.

Longitudinal effects of cognitive fusion in depressive and anxious symptoms of family caregivers of people with dementia.

Family dementia caregiving has been commonly associated with psychological distress for caregivers. Cognitive fusion, that is, the tendency to become too entangled in thoughts, beliefs, or judgments (in the absence of objectivity) that may often lead to rigid thinking and impact psychological distress, is a transdiagnostic and central process of psychological inflexibility. Cross-sectional studies have shown that family caregivers of people with dementia who could present high levels of stress may be vulnerable to experiencing psychological symptoms such as depression and anxiety (even comorbidity) if they present this rigid way of thinking without seeing the objectivity of their thoughts, which could be related to aspects of the family member's dementia or helplessness in being a caregiver, for example. Specifically, studies in the caregiving field, as well as in other populations, suggest that cognitive fusion could play a mediating role in the relationship between stress and psychological symptoms. However, the predictive role of caregivers' cognitive fusion on psychological distress has not been analyzed in longitudinal studies. The objective of this study was to analyze the longitudinal effect of cognitive fusion in depressive and anxious symptoms after controlling for other relevant variables in a sample of Spanish family caregivers. Face to face assessments were conducted with a total of 176 Spanish family dementia caregivers. The study involved three assessments in a two-year period (baseline, 12 and 24 months). Linear mixed model analysis was used to analyze the associations between time-varying values of frequency and reaction to care-recipient behavioral problems, cognitive fusion, and caregivers' depressive and anxiety symptoms. Increases in cognitive fusion significantly predicted depressive and anxious symptoms (p < 0.01). In addition, reaction to care-recipients’ behavioral problems and being a female caregiver predicted increases in anxiety symptoms over time (p < 0.05). These results suggested that cognitive fusion may constitute a core dysfunctional mechanism involved in depressive and anxious symptoms. Psychological strategies aimed at reducing cognitive fusion and stress levels may be especially helpful for reducing caregivers' distress.

The Paradox of Aging-Related Fears: Fear of Loneliness in Old Age as a Motivator for Loneliness Preventive Activities

Introduction: Aging is often seen as a challenging process, prompting individuals to form emotional reactions in response to the perceived challenges associated with growing older, manifested as aging-related fears. The present study focuses on the fear of loneliness in old age, a significant concern considering the socioemotional importance of close relationships in later life. Drawing from proactive coping theory, the study explores the association between fear of loneliness and aging preparation. This research aimed to investigate whether the fear of loneliness motivates individuals to engage in activities aimed at preventing loneliness in old age. For exploratory purposes, we consider both linear and nonlinear effects at the interindividual level, as well as the intraindividual-level differences between fear levels and behavioral outcomes. In addition, we also investigate the moderating role of trait neuroticism in these associations. Methods: Data from the “Ageing as Future (AAF)” project in Germany (N = 1,183) spanning from 2012 to 2023 were utilized. A multilevel model considered both intra- and interindividual variations, incorporating time-varying variables and covariates. Results: Linear mixed model analysis revealed that increased fear of loneliness corresponded to heightened engagement in preventive activities linearly, while a quadratic term indicated an inverted U-shaped relationship. The inclusion of occasion-specific deviation scores showed that individuals were more inclined to engage in preventive activities when experiencing heightened fear of loneliness than usual. This impact of deviation in fear perception was particularly evident among those with high levels of trait neuroticism. Conclusion: The study reveals that fear of loneliness in old age is associated with proactive engagement in preventive activities, with those prone to higher levels of fear or worry being particularly affected. These results emphasize the importance of a moderate level of fear in driving action without succumbing to excessive pessimism or unrealistic optimism. The findings contribute to understanding the motivational role of aging-related fears and hold implications for gerontological practices, emphasizing the need for a balanced fear perception in addressing potential negative impacts of aging. Future research could explore moderators and long-term consequences of motivational aging-related fears.

Maintaining the validity of inference from linear mixed models in stepped-wedge cluster randomized trials under misspecified random-effects structures.

Linear mixed models are commonly used in analyzing stepped-wedge cluster randomized trials. A key consideration for analyzing a stepped-wedge cluster randomized trial is accounting for the potentially complex correlation structure, which can be achieved by specifying random-effects. The simplest random effects structure is random intercept but more complex structures such as random cluster-by-period, discrete-time decay, and more recently, the random intervention structure, have been proposed. Specifying appropriate random effects in practice can be challenging: assuming more complex correlation structures may be reasonable but they are vulnerable to computational challenges. To circumvent these challenges, robust variance estimators may be applied to linear mixed models to provide consistent estimators of standard errors of fixed effect parameters in the presence of random-effects misspecification. However, there has been no empirical investigation of robust variance estimators for stepped-wedge cluster randomized trials. In this article, we review six robust variance estimators (both standard and small-sample bias-corrected robust variance estimators) that are available for linear mixed models in R, and then describe a comprehensive simulation study to examine the performance of these robust variance estimators for stepped-wedge cluster randomized trials with a continuous outcome under different data generators. For each data generator, we investigate whether the use of a robust variance estimator with either the random intercept model or the random cluster-by-period model is sufficient to provide valid statistical inference for fixed effect parameters, when these working models are subject to random-effect misspecification. Our results indicate that the random intercept and random cluster-by-period models with robust variance estimators performed adequately. The CR3 robust variance estimator (approximate jackknife) estimator, coupled with the number of clusters minus two degrees of freedom correction, consistently gave the best coverage results, but could be slightly conservative when the number of clusters was below 16. We summarize the implications of our results for the linear mixed model analysis of stepped-wedge cluster randomized trials and offer some practical recommendations on the choice of the analytic model.

Hypermethylation of BMPR2 and TGF-β Promoter Regions in Tibetan Patients with High-Altitude Polycythemia at Extreme Altitude.

Although the expression of many genes is associated with adaptation to high-altitude hypoxic environments, the role of epigenetics in the response to this harsh environmental stress is currently unclear. We explored whether abnormal DNA promoter methylation levels of six genes, namely, ABCA1, SOD2, AKT1, VEGFR2, TGF-β, and BMPR2, affect the occurrence and development of high-altitude polycythemia (HAPC) in Tibetans. The methylation levels of HAPC and the control group of 130 Tibetans from very high altitudes (> 4500m) were examined using quantitative methylation-specific real-time PCR (QMSP). Depending on the type of data, the Pearson chi-square test, Wilcoxon rank-sum test, and Fisher exact test were used to assess the differences between the two groups. The correlation between the methylation levels of each gene and the hemoglobin content was explored using a linear mixed model. Our experiment revealed that the methylation levels of the TGF-β and BMPR2 genes differed significantly in the two groups (p < 0.05) and linear mixed model analysis showed that the correlation between the hemoglobin and methylation of ABCA1, TGF-β, and BMPR2 was statistically significant (p < 0.05). Our study suggests that levels of TGF-β and BMPR2 methylation are associated with the occurrence of HAPC in extreme-altitude Tibetan populations among 6 selected genes. Epigenetics may be involved in the pathogenesis of HAPC, and future experiments could combine gene and protein levels to verify the diagnostic value of TGF-β and BMPR2 methylation levels in HAPC.