Tag: statistics

J Psychiatry Neurosci. 2021 Mar 11;46(2):E222-E231. doi: 10.1503/jpn.200091.

ABSTRACT

BACKGROUND: Previous studies have suggested that processing of visual contrast information could be altered in major depressive disorder. To clarify the changes at different levels of the visual hierarchy, we behaviourally measured contrast perception in 2 centre-surround conditions, assessing retinal and cortical processing.

METHODS: As part of a prospective cohort study, our sample consisted of controls (n = 29; 21 female) and patients with unipolar depression, bipolar disorder and borderline personality disorder who had baseline major depressive episodes (n = 111; 74 female). In a brightness induction test that assessed retinal processing, participants compared the perceived luminance of uniform patches (presented on a computer screen) as the luminance of the backgrounds was varied. In a contrast suppression test that assessed cortical processing, participants compared the perceived contrast of gratings, which were presented with collinearly or orthogonally oriented backgrounds.

RESULTS: Brightness induction was similar for patients with major depressive episodes and controls (p = 0.60, d = 0.115, Bayes factor = 3.9), but contrast suppression was significantly lower for patients than for controls (p < 0.006, d = 0.663, Bayes factor = 35.2). We observed no statistically significant associations between contrast suppression and age, sex, or medication or diagnostic subgroup. At follow-up (n = 74), we observed some normalization of contrast perception.

LIMITATIONS: We assessed contrast perception using behavioural tests instead of electrophysiology.

CONCLUSION: The reduced contrast suppression we observed may have been caused by decreased retinal feedforward or cortical feedback signals. Because we observed intact brightness induction, our results suggest normal retinal but altered cortical processing of visual contrast during a major depressive episode. This alteration is likely to be present in multiple types of depression and to partially normalize upon remission.

PMID:33703869 | DOI:10.1503/jpn.200091

J Osteopath Med. 2021 Feb 25. doi: 10.1515/jom-2020-0198. Online ahead of print.

ABSTRACT

CONTEXT: Medical students are faced with the challenge of synthesizing large volumes of information quickly. With the increasing accessibility of technology, a “flipped classroom” allows students to learn foundational material independently. Class time is instead devoted to in-depth skill building with instructors, promoting an active learning environment. This method of content delivery is also relevant given the current COVID-19 pandemic.

OBJECTIVES: To comprehensively evaluate the benefit of adopting a flipped classroom approach in teaching physical exam skills (PES) to first-year osteopathic medical students.

METHODS: A cohort study was conducted comparing first-year osteopathic students in the class of 2022 (n=201), who had taken the PES course traditionally, with the class of 2023 (n=203), who experienced the flipped classroom approach. Objective metrics such as cumulative grades, objective structural clinical examination performance (OSCE), and practical exam performance were compared using nonparametric Mann-Whitney U rank sum tests. Subjective measures such as student course evaluations were used to analyze course perceptions using independent sample t-tests assuming unequal variances. A faculty survey was administered to faculty who taught both cohorts to assess instructor attitudes toward the flipped classroom approach. Due to the COVID-19 pandemic, Spring 2020 quarter data was not included, given the transition of all classes to an online learning environment.

RESULTS: The flipped classroom approach significantly improved objective student performance for the Fall (p=0.009) and Winter (p<0.001) student cumulative grades and the History-Taking OSCE (p=0.010). Performance on Fall and Winter practical exam scores had no significant association with the flipped classroom. General student perceptions of the course remained unchanged between both cohorts. Faculty survey results from 10 faculty members showed that six (60%) faculty members preferred the traditional classroom, while four (40%) preferred the flipped classroom.

CONCLUSIONS: The flipped classroom approach showed some statistically significant improvement in student PES. Further studies are needed to evaluate the benefits of a flipped classroom approach using skills-based assessments styles to measure student performance, with a focus on standardization of in-classroom groupwork.

PMID:33694343 | DOI:10.1515/jom-2020-0198

J Osteopath Med. 2021 Feb 22. doi: 10.1515/jom-2020-0251. Online ahead of print.

ABSTRACT

CONTEXT: Medical students, especially at osteopathic medical schools, have limited research exposure. Systematic instruction in research, supervised by qualified mentors, could motivate osteopathic medical students to pursue research in their careers, thereby increasing the number of future clinician-scientists. Recruiting and retaining suitable research mentors are crucial to sustaining such programs, but this task is also particularly challenging for osteopathic medical schools.

OBJECTIVES: To assess mentors’ experiences in a voluntary student-mentor medical research program.

METHODS: An online survey was sent to 76 university- or hospital-based participants who previously mentored 219 medical students between 2014 and 2019. The questionnaire consisted of 13 items with responses in checklist, five-point Likert scale, and categorical multiple-choice formats, assessing motivation for participation, satisfaction with the program, and interest in future participation. Data were analyzed descriptively, and responses from mentors at the university and hospital were compared using univariate logistic and ordinal regression analyses.

RESULTS: Among 70 (92.1%) mentors who responded to the survey, 61 (87.1%) reported being motivated by a desire to help medical students learn research. Forty-nine (70.0%) mentors indicated that furthering their own research productivity was a motivation, and hospital-based mentors were statistically significantly more likely to endorse this source of motivation (OR=2.02; 95% CI=1.18-3.45; p=0.01). Most respondents were satisfied with the quality of the students’ work (59 [84.3%]) and with the program (59 [85.5%]). However, 46 (65.7%) suggested the program could be enhanced by requiring medical students to be physically present in the clinic or laboratory for a minimum amount of time. Importantly, most (58 [84.1%]) mentors reported that they would be interested in participating in future mentored research programs.

CONCLUSIONS: Mentors were motivated to participate in the voluntary research program for both altruistic and professional reasons. Since most mentors reported being satisfied with the program, it is likely they would participate in future mentored research programs. Our results suggest that mentors viewed this voluntary research program as mutually beneficial.

PMID:33694344 | DOI:10.1515/jom-2020-0251

J Osteopath Med. 2021 Feb 17. doi: 10.1515/jom-2020-0272. Online ahead of print.

ABSTRACT

CONTEXT: In March 2020, the World Health Organization declared the novel coronavirus disease 2019 (COVID-19) outbreak a pandemic. Due to the rapid spread, strong contagion, high incidence of lethality in severe cases, and the lack of a pharmaceutical prevention or cure, COVID-19 has posed a serious threat to human life and health. It has also had a tremendous impact on mental health, including fear and worry, difficulty sleeping or concentrating, and increased use of poor coping mechanisms. Osteopathic medical students have had additional concerns regarding the interruption of their studies, closing of clinical rotations, and postponed licensing exams. To date, few reports have focused on osteopathic medical students and their reactions to the outbreak.

OBJECTIVES: To assess resilience, coping, health behaviors, and emotional wellbeing of osteopathic medical students during the onset of the COVID-19 pandemic.

METHODS: In this cross-sectional study, we distributed an anonymous online survey to all medical students enrolled at Nova Southeastern University in May 2020 (n=1,310) via an e-mail invitation using the institution’s student listservs. Our major study variables were based on published reports and anecdotal evidence; we subsequently developed the Emotional Wellbeing in Healthcare Professions Students Questionnaire (EWB-Q). This EWB-Q contained validated scales to assess the contribution of levels of coping strategies used, personal resilience, and health behaviors on the emotional wellbeing of osteopathic medical students. Multiple linear regression and other statistical analyses were conducted using SPSS v0.26.

RESULTS: Of the 1,310 students invited to participate, 335 (25.5%) surveys were returned. Of those, 133 had more than 33% of the necessary data missing and were removed, resulting in 202 (15.4%) completed questionnaires. The mean age of the participants was 26.7 years. About half (n=92; 45.5%) were in the clinical phase (years 3 and 4) of their medical school training (in rotations). A significant regression equation was found (F[4,171]=17.481, p<0.000, R ² =0.290, R ^2adjusted=0.274), indicating that levels of coping, personal resilience, and health behaviors (i.e., not sleeping more than usual, not exercising less than usual) accounted for a significant amount of the variance in emotional wellbeing scores in osteopathic medical students. Higher levels of resilience, greater use of coping strategies, not sleeping more than usual, and not exercising less than usual were predictors of emotional wellbeing.

CONCLUSIONS: Cultivating positive mental health should be a high priority for medical educators as they develop and implement curriculum-based initiatives to help medical students bolster their personal resilience and to encourage healthy coping behaviors during times of crisis and beyond. A proactive position that assists with building personal resilience and developing stress management habits is paramount in assisting students who are grappling not only with the challenges of rigorous medical training, but also with the uncertainty and stress that exists during any major global health or socioeconomic crisis.

PMID:33694347 | DOI:10.1515/jom-2020-0272

J Osteopath Med. 2021 Feb 23. doi: 10.1515/jom-2020-0268. Online ahead of print.

ABSTRACT

CONTEXT: Back injuries have a high prevalence in the United States and can be costly for both patients and the healthcare system at large. While previous guidelines from the American College of Physicians for the management of acute nonspecific low back pain (ANLBP) have encouraged nonpharmacologic management, those treatment recommendations involved only superficial heat, massage, acupuncture, and spinal manipulation. Investigation about the efficacy of spinal manipulation in the management of ANLBP is warranted.

OBJECTIVES: To compare the results in previously-published literature documenting the outcomes of osteopathic manipulative treatment (OMT) techniques used to treat ANLBP. The secondary objective of this study was to demonstrate the utility of using Bayesian network meta-analysis (NMA) to perform a mixed treatment comparison (MTC) of a variety of osteopathic techniques.

METHODS: A literature search for randomized controlled trials (RCTs) of ANLBP treatments was performed in April 2020 according to PRISMA guidelines by searching MEDLINE/PubMed, OVID, Cochrane Central, PEDro, and OSTMED.Dr databases; scanning the reference lists of articles; and using the Canadian Agency for Drugs and Technologies in Health grey literature checklist. Each database was searched from inception to April 1, 2020. The following search terms were used: acute low back pain, acute low back pain plus physical therapy, acute low back pain plus spinal manipulation, and acute low back pain plus osteopathic manipulation. The validity of eligible trials was assessed by the single author using an adapted National Institute for Health and Care Excellence methodology checklist for randomized, controlled trials and an extraction form based on that checklist. The outcome measure chosen for this NMA was the Visual Analogue Scale of pain. The NMA were performed using the GeMTC user interface for automated NMA utilizing a Bayesian hierarchical model of random effects.

RESULTS: The literature search initially found 483 unduplicated records. After screening and full text assessment, five RCTs were eligible for the MTC, yielding a total of 430 participants. Results of the MTC model suggested that there was no statistically significant decrease in reported pain when exercise, high-velocity low-amplitude (HVLA), counterstrain, muscle energy technique, or a mix of techniques were added to conventional treatment to treat ANLBP. However, the rank probabilities assessment determined that HVLA and the OMT mixed treatment protocol plus conventional care were ranked superior to conventional care alone for improving ANLBP.

CONCLUSIONS: While this study failed to provide definitive evidence upon which clinical recommendations can be based, it does demonstrate the utility of performing NMA for MTCs of osteopathic modalities used to treat ANLBP. However, to take full advantage of this statistical technique, future studies should be designed with consideration for the methodological shortcomings found in past osteopathic research.

PMID:33694350 | DOI:10.1515/jom-2020-0268

Brain Behav. 2021 Mar 10:e02103. doi: 10.1002/brb3.2103. Online ahead of print.

ABSTRACT

INTRODUCTION: The current diagnosis of Parkinson’s disease (PD) comorbidity with depression (DPD) largely depends on clinical evaluation. However, the modality may tend to lack precision in detecting PD with depression. A radiomic approach that combines functional connectivity and activity with clinical scores has the potential to achieve accurate and differential diagnosis between PD and DPD.

METHODS: In this study, we aimed to employ the radiomic approach to extract large-scale features of functional connectivity and activity for differentiating among DPD, PD with no depression (NDPD), and healthy controls (HC). We extracted 6,557 features of five types from all subjects including clinical characteristics, resting-state functional connectivity (RSFC), amplitude of low-frequency fluctuation (ALFF), regional homogeneity (ReHo), and voxel-mirrored homotopic connectivity (VMHC). Lasso, random forest, and support vector machine (SVM) were implemented for feature selection and dimension reduction based on the training sets, and the prediction performance for different methods in the testing sets was compared.

RESULTS: The results showed that nineteen features were selected for the group of DPD versus HC, 34 features were selected for the group of NDPD versus HC, and 17 features were retained for the group of DPD versus NDPD. In the testing sets, Lasso prediction achieved the accuracies of 0.95, 0.96, and 0.85 for distinguishing between DPD and HC, NDPD and HC, and DPD and NDPD, respectively. Random forest achieved the accuracies of 0.90, 0.82, and 0.90 for distinguishing between DPD and HC, NDPD and HC, and DPD and NDPD, respectively, while SVM yielded the accuracies of 1, 0.86 and 0.65 for distinguishing between DPD and HC, NDPD and HC, and DPD and NDPD, respectively.

CONCLUSIONS: By identifying aberrant functional connectivity and activity as potential biomarkers, the radiomic approach facilitates a deeper understanding and provides new insights into the pathophysiology of DPD to support the clinical diagnosis with high prediction accuracy.

PMID:33694328 | DOI:10.1002/brb3.2103

J Magn Reson Imaging. 2021 Mar 10. doi: 10.1002/jmri.27587. Online ahead of print.

ABSTRACT

BACKGROUND: Vessel-wall enhancement (VWE) on black-blood MRI (BB MRI) has been proposed as an imaging marker for a higher risk of rupture and associated with wall inflammation. Whether VWE is causally linked to inflammation or rather induced by flow phenomena has been a subject of debate.

PURPOSE: To study the effects of slow flow, spatial resolution, and motion-sensitized driven equilibrium (MSDE) preparation on signal intensities in BB MRI of patient-specific aneurysm flow models.

STUDY TYPE: Prospective.

SUBJECTS/FLOW ANEURYSM MODEL/VIRTUAL VESSELS: Aneurysm flow models based on 3D rotational angiography datasets of three patients with intracranial aneurysms were 3D printed and perfused at two different flow rates, with and without Gd-containing contrast agent.

FIELD STRENGTH/SEQUENCE: Variable refocusing flip angle 3D fast-spin echo sequence at 3 T with and without MSDE with three voxel sizes ((0.5 mm)³ , (0.7 mm)³ , and (0.9 mm)³ ); time-resolved with phase-contrast velocity-encoding 3D spoiled gradient echo sequence (4D flow MRI).

ASSESSMENT: Three independent observers performed a qualitative visual assessment of flow patterns and signal enhancement. Quantitative analysis included voxel-wise evaluation of signal intensities and magnitude velocity distributions in the aneurysm.

STATISTICAL TESTS: Kruskal-Wallis test, potential regressions.

RESULTS: A hyperintense signal in the lumen and adjacent to the aneurysm walls on BB MRI was colocalized with slow flow. Signal intensities increased by a factor of 2.56 ± 0.68 (P < 0.01) after administering Gd contrast. After Gd contrast administration, the signal was suppressed most in conjunction with high flows and with MSDE (2.41 ± 2.07 for slow flow without MSDE, and 0.87 ± 0.99 for high flow with MSDE). A clear result was not achieved by modifying the spatial resolution .

DATA CONCLUSIONS: Slow-flow phenomena contribute substantially to aneurysm enhancement and vary with MRI parameters. This should be considered in the clinical setting when assessing VWE in patients with an unruptured aneurysm.

EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 2.

PMID:33694334 | DOI:10.1002/jmri.27587

J Osteopath Med. 2021 Mar 2. doi: 10.1515/jom-2020-0132. Online ahead of print.

ABSTRACT

CONTEXT: Lower back pain (LBP) is prevalent and is a leading contributor to disease burden worldwide. Osteopathic manipulative treatment (OMT) can alleviate alterations in the body that leads to musculoskeletal disorders such as LBP. Bio-electromagnetic Energy Regulation (BEMER; BEMER International AG), which has also been shown to relieve musculoskeletal pain, is a therapeutic modality that deploys a biorhythmically defined stimulus through a pulsed electromagnetic field (PEMF). Therefore, it is possible that combined OMT and BEMER therapy could reduce low back pain in adults more than the effect of either treatment modality alone.

OBJECTIVES: To investigate the individual and combined effects of OMT and BEMER therapy on LBP in adults.

METHODS: Employees and students at a medical college were recruited to this study by email. Participants were included if they self-reported chronic LBP of 3 months’ duration or longer; participants were excluded if they were experiencing acute LBP of 2 weeks’ duration or less, were currently being treated for LBP, were pregnant, or had a known medical history of several conditions. Ultimately, 40 participants were randomly assigned to four treatment groups: an OMT only, BEMER only, OMT+BEMER, or control (light touch and sham). Treatments were given regularly over a 3 week period. Data on LBP and quality of life were gathered through the Visual Analog Scale (VAS), Short Form 12 item (SF-12) health survey, and Oswestry Low Back Pain Questionnaire/Oswestry Disability Index prior to treatment and immediately after the 3 week intervention protocol. One-way analysis of variance (ANOVA) was performed retrospectively and absolute changes for each participant were calculated. Normal distribution and equal variances were confirmed by Shapiro-Wilk test (p>0.05) and Brown-Forsythe, respectively. Significance was set at p<0.05.

RESULTS: Despite a lack of statistical significance between groups, subjective reports of pain reported on the VAS showed a substantial mean percentage decrease (50.8%) from baseline in the OMT+BEMER group, compared with a 10.2% decrease in the OMT-only and 9.8% in BEMER-only groups when comparing the difference in VAS ratings from preintervention to postintervention. Participants also reported in quality of life assessed on the Oswestry Low Back Pain Questionnaire/Oswestry Disability Index, with the OMT+BEMER group showing a decrease of 30.3% in score, the most among all groups. The OMT+BEMER group also reported the greatest improvement in score in the physical component of the SF-12, with an increase of 21.8%.

CONCLUSIONS: The initial data from this study shows a potential additive effect of combination therapy (OMT and BEMER) for management of LBP, though the results did not achieve statistical significance.

PMID:33694338 | DOI:10.1515/jom-2020-0132

Eur J Cancer Care (Engl). 2021 Mar 10:e13436. doi: 10.1111/ecc.13436. Online ahead of print.

ABSTRACT

OBJECTIVE: The aim of study was to determine factors affecting the medical healthcare-seeking behaviours of female patients according to their stage of being diagnosed with breast cancer.

METHODS: This descriptive and correlational study was carried out with 150 women. The data were collected by a survey form, the Body Perception Scale, the Rosenberg Self-Esteem Scale and the Social Appearance Anxiety Scale.

RESULTS: About 54% of the women were diagnosed with early-stage breast cancer, 68.7% had high self-esteem, and 80% had positive body perceptions, while their social appearance anxiety levels were moderate. The patients with breast cancer at the 4th stage had a high body perception score of 174.00 ± 23.34. Self-esteem was the highest in the patients with stage 2B breast cancer with a value of 0.61 ± 0.91. The highest social anxiety mean score was found in the patients with stage 2A breast cancer as 31.65 ± 12.50. There was no statistically significant difference in the women’s sociodemographic characteristics, health and breast cancer history, self-esteem, body perception and social appearance anxiety based on their stages of cancer (p > 0.05).

CONCLUSION: Nurses’ identification of risky individuals in early diagnosis, information for the individual / family and society by planning trainings and raising awareness will contribute positively to the patients’ medical health-seeking behaviours.

PMID:33694269 | DOI:10.1111/ecc.13436

Ann Clin Transl Neurol. 2021 Mar 11. doi: 10.1002/acn3.51331. Online ahead of print.

ABSTRACT

OBJECTIVE: To assess associations between head injury (HI) with loss of consciousness (LOC), ageing and markers of later-life cerebral pathology; and to explore whether those effects may help explain subtle cognitive deficits in dementia-free individuals.

METHODS: Participants (n = 502, age = 69-71) from the 1946 British Birth Cohort underwent cognitive testing (subtests of Preclinical Alzheimer Cognitive Composite), ¹⁸ F-florbetapir Aβ-PET and MR imaging. Measures include Aβ-PET status, brain, hippocampal and white matter hyperintensity (WMH) volumes, normal appearing white matter (NAWM) microstructure, Alzheimer’s disease (AD)-related cortical thickness, and serum neurofilament light chain (NFL). LOC HI metrics include HI occurring: (i) >15 years prior to the scan (ii) anytime up to age 71.

RESULTS: Compared to those with no evidence of an LOC HI, only those reporting an LOC HI>15 years prior (16%, n = 80) performed worse on cognitive tests at age 69-71, taking into account premorbid cognition, particularly on the digit-symbol substitution test (DSST). Smaller brain volume (BV) and adverse NAWM microstructural integrity explained 30% and 16% of the relationship between HI and DSST, respectively. We found no evidence that LOC HI was associated with Aβ load, hippocampal volume, WMH volume, AD-related cortical thickness or NFL (all p > 0.01).

INTERPRETATION: Having a LOC HI aged 50’s and younger was linked with lower later-life cognitive function at age ~70 than expected. This may reflect a damaging but small impact of HI; explained in part by smaller BV and different microstructure pathways but not via pathology related to AD (amyloid, hippocampal volume, AD cortical thickness) or ongoing neurodegeneration (serum NFL).

PMID:33694298 | DOI:10.1002/acn3.51331