Category: Statistics

J Orthop Surg Res. 2023 Apr 5;18(1):280. doi: 10.1186/s13018-023-03763-z.

ABSTRACT

BACKGROUND: This study aimed to quantitatively evaluate lateral center-edge angle (LCEA) and anterior center-edge angle (ACEA) according to sex and the anterior pelvic plane (APP) tilt angle and analyze the correlation between these measurements and acetabular coverage.

METHODS: Computed tomography scans of 71 adults (38 men and 33 women) with normal hip joints were obtained. LCEA, anterior ACEA, and acetabular coverage were measured with APP tilt every 5° from – 30° to + 30° and were compared between the sexes. The correlation between acetabular coverage and LCEA/ACEA was also analyzed.

RESULTS: (1) LCEA, ACEA, and acetabular coverage were statistically larger in men than in women at all APP tilt angles (with the exception of acetabular coverage ≥ 25°). (2) LCEA, ACEA, and acetabular coverage differed according to APP tilt angle. LCEA and acetabular coverage showed maximum values at 10°. ACEA showed a tendency to increase by an average of 3.6° for every 5° increase in the APP tilt angle. LCEA demonstrated strong and very strong associations across all APP tilting angles, whereas ACEA showed a moderate association at angles ≥ 15° in men and ≥ 30° in women.

CONCLUSIONS: The LCEA and ACEA are adequate measurement methods that reflect actual acetabular coverage unless the pelvis is tilted excessively anteriorly. While pelvic tilting does not need to be considered for LCEA within the physiologic range, it should always be taken into account for ACEA, as it increases by an average of 3.6° for every 5° increase in APP tilt angle.

LEVEL OF EVIDENCE: Level III: retrospective cohort study.

PMID:37020213 | DOI:10.1186/s13018-023-03763-z

BMC Med Educ. 2023 Apr 5;23(1):217. doi: 10.1186/s12909-023-04182-8.

ABSTRACT

BACKGROUND: Rural medical training experiences provided by Rural Clinical Schools (RCS) can encourage future practice in rural locations. However, the factors influencing students’ career choices are not well understood. This study explores the influence of undergraduate rural training experiences on graduates’ subsequent practice location.

METHODS: This retrospective cohort study included all medical students who completed a full academic year at the University of Adelaide RCS training program between 2013-2018. Details of student characteristics, experiences, and preferences were extracted from the Federation of Rural Australian Medical Educators (FRAME, 2013-2018) survey and linked to graduates’ recorded practice location obtained from the Australian Health Practitioner Regulation Agency (AHPRA, January 2021). The rurality of the practice location was defined based on the Modified Monash Model (MMM 3-7) or Australian Statistical Geography Standard (ASGS 2-5). Logistic regression was used to examine associations between student rural training experiences and rural practice location.

RESULTS: A total of 241 medical students (60.1% females; mean age 23.2 ± 1.8 years) completed the FRAME survey (response rate 93.2%). Of these, 91.7% felt well supported, 76.3% had a rural-based clinician mentor, 90.4% reported increased interest in a rural career, and 43.6% preferred a rural practice location after graduation. Practice locations were identified for 234 alumni, and 11.5% were working rurally in 2020 (MMM 3-7; 16.7% according to ASGS 2-5). In adjusted analysis, the odds of working rurally were 3-4 times more likely among those with a rural background or lived the longest in a rural location, 4-12 times more likely among those preferring a rural practice location after graduation, and increased with the student’s rural practice self-efficacy score (p-value < 0.05 in all cases). Neither the perceived support, having a rural-based mentor, or the increased interest in a rural career were associated with the practice location.

CONCLUSIONS: These RCS students consistently reported positive experiences and increased interest in rural practice after their rural training. Student reported preference for a rural career and rural practice self-efficacy score were significant predictors of subsequent rural medical practice. Other RCS could use these variables as indirect indicators of the impact of RCS training on the rural health workforce.

PMID:37020211 | DOI:10.1186/s12909-023-04182-8

Reprod Biol Endocrinol. 2023 Apr 5;21(1):35. doi: 10.1186/s12958-023-01087-5.

ABSTRACT

BACKGROUND: To study whether AMH levels were associated with miscarriage rates in index ART cycles undergoing fresh autologous transfers in PCOS and non-PCOS related infertility.

METHODS: In the SART CORS database 66,793 index cycles underwent fresh autologous embryo transfers with AMH values reported within the last 1-year between 2014 and 2016. Cycles that resulted in ectopic or heterotopic pregnancies, or were performed for embryo/oocyte banking were excluded. Data were analyzed using Graphpad Prism-9. Odds ratios (OR) were calculated with 95% confidence intervals (CI) along with multivariate regression analysis adjusting for age, body mass index (BMI), and number of embryos transferred. Miscarriage rates were calculated as miscarriage per clinical pregnancies.

RESULTS: Of the total 66,793 cycles, the mean AMH was 3.2 ng/ml and were not associated with increased miscarriage rates for AMH < 1 ng/ml (OR 1.1, CI 0.9-1.4, p = 0.3). Of the 8,490 PCOS patients, the mean AMH was 6.1 ng/ml and were not associated with increased miscarriage rates for AMH < 1 ng/ml (OR 0.8, CI 0.5-1.1, p = 0.2). Of the 58,303 non-PCOS patients, the mean AMH was 2.8 ng/ml and there was a significant difference in miscarriage rates for AMH < 1 ng/ml (OR 1.2, CI 1.1-1.3, p < 0.01). All findings were independent of age, BMI and number of embryos transferred. This statistical significance did not persist at higher thresholds of AMH. The overall miscarriage rate for all cycles, and cycles with and without PCOS were each 16%.

DISCUSSION: The clinical utility of AMH continues to increase as more studies investigate its predictive abilities regarding reproductive outcomes. This study adds clarity to the mixed findings of prior studies that have examined the relationship between AMH and miscarriage in ART cycles. AMH values of the PCOS population are higher than the non-PCOS. The elevated AMH associated with PCOS decreases its utility in predicting miscarriages in IVF cycles as it may be representing the number of developing follicles rather than oocyte quality in the PCOS patient population. The elevated AMH associated with PCOS may have skewed the data; removing this sub-population may have unmasked significance within the non-PCOS associated infertility.

CONCLUSIONS: AMH < 1 ng/mL is an independent predictor of increased miscarriage rate in patients with non-PCOS infertility.

PMID:37020210 | DOI:10.1186/s12958-023-01087-5

BMC Ophthalmol. 2023 Apr 5;23(1):140. doi: 10.1186/s12886-023-02888-3.

ABSTRACT

PURPOSE: To study the types of uveitis examined in a hospital serving indigent populations in need of low-cost care.

METHODS: A retrospective chart review examined the electronic medical records of all patients with uveitis-related at Drexel Eye Physicians. Data collected included demographics, anatomic location of the uveitis, systemic disease associations, treatment modalities and insurance. Statistical analysis was performed using χ² or Fischer exact tests.

RESULTS: 270 patients (366 eyes) were included for analysis, 67% of patients identified as African American. Most eyes (95.3%, N = 349) were treated with topical corticosteroid drops, and only 6 (1.6%) received an intravitreal implant. Immunosuppressive medications were started in 24 patients (8.9%). Nearly 80% depended to some extent on Medicare or Medicaid Assistance for treatment coverage. There was no association between insurance type and use of biologics or difluprednate.

CONCLUSION: We found no association between insurance type and the prescription of medications for uveitis that should be used at home. There was a minimal number of patients prescribed medications for implantation in the office. The adherence of use of medications at home should be investigated.

PMID:37020208 | DOI:10.1186/s12886-023-02888-3

BMC Med Res Methodol. 2023 Apr 5;23(1):83. doi: 10.1186/s12874-023-01901-z.

ABSTRACT

BACKGROUND: National mortality statistics are based on a single underlying cause of death. This practice does not adequately represent the impact of the range of conditions experienced in an ageing population in which multimorbidity is common.

METHODS: We propose a new method for weighting the percentages of deaths attributed to different causes that takes account of the patterns of associations among underlying and contributing causes of death. It is driven by the data and unlike previously proposed methods does not rely on arbitrary choices of weights which can over-emphasise the contribution of some causes of death. The method is illustrated using Australian mortality data for people aged 60 years or more.

RESULTS: Compared to the usual method based only on the underlying cause of death the new method attributes higher percentages of deaths to conditions like diabetes and dementia that are frequently mentioned as contributing causes of death, rather than underlying causes, and lower percentages to conditions to which they are closely related such as ischaemic heart disease and cerebrovascular disease. For some causes, notably cancers, which are usually recorded as underlying causes with few if any contributing causes the new method produces similar percentages to the usual method. These different patterns among groups of related conditions are not apparent if arbitrary weights are used.

CONCLUSION: The new method could be used by national statistical agencies to produce additional mortality tables to complement the current tables based only on underlying causes of death.

PMID:37020203 | DOI:10.1186/s12874-023-01901-z

BMC Bioinformatics. 2023 Apr 5;24(1):135. doi: 10.1186/s12859-023-05169-4.

ABSTRACT

BACKGROUND: Population structure and cryptic relatedness between individuals (samples) are two major factors affecting false positives in genome-wide association studies (GWAS). In addition, population stratification and genetic relatedness in genomic selection in animal and plant breeding can affect prediction accuracy. The methods commonly used for solving these problems are principal component analysis (to adjust for population stratification) and marker-based kinship estimates (to correct for the confounding effects of genetic relatedness). Currently, many tools and software are available that analyze genetic variation among individuals to determine population structure and genetic relationships. However, none of these tools or pipelines perform such analyses in a single workflow and visualize all the various results in a single interactive web application.

RESULTS: We developed PSReliP, a standalone, freely available pipeline for the analysis and visualization of population structure and relatedness between individuals in a user-specified genetic variant dataset. The analysis stage of PSReliP is responsible for executing all steps of data filtering and analysis and contains an ordered sequence of commands from PLINK, a whole-genome association analysis toolset, along with in-house shell scripts and Perl programs that support data pipelining. The visualization stage is provided by Shiny apps, an R-based interactive web application. In this study, we describe the characteristics and features of PSReliP and demonstrate how it can be applied to real genome-wide genetic variant data.

CONCLUSIONS: The PSReliP pipeline allows users to quickly analyze genetic variants such as single nucleotide polymorphisms and small insertions or deletions at the genome level to estimate population structure and cryptic relatedness using PLINK software and to visualize the analysis results in interactive tables, plots, and charts using Shiny technology. The analysis and assessment of population stratification and genetic relatedness can aid in choosing an appropriate approach for the statistical analysis of GWAS data and predictions in genomic selection. The various outputs from PLINK can be used for further downstream analysis. The code and manual for PSReliP are available at https://github.com/solelena/PSReliP .

PMID:37020193 | DOI:10.1186/s12859-023-05169-4

BMC Infect Dis. 2023 Apr 5;23(1):201. doi: 10.1186/s12879-023-08203-1.

ABSTRACT

BACKGROUND: Both post-COVID-19 condition (long COVID) and the presence of persisting symptoms that do not meet formal definitions of post-COVID-19-condition may adversely affect quality of life and function. However, their prevalence among children and young people in England is unclear.

METHODS: We used data from repeated surveys in a large cohort of English schoolchildren from the COVID-19 Schools Infection Survey (SIS) for the school year 2021/22 to describe the weighted prevalence of post-COVID-19-condition and compare persisting symptoms between individuals with a positive SARS-CoV-2 test and those with neither a positive test history nor suspected infection.

RESULTS: Among 7797 children from 173 schools, 1.8% of primary school pupils (aged 4 to 11 years), 4.5% of secondary school pupils in years 7-11 (aged 11 to 16 years) and 6.9% of those in years 12-13 (aged 16 to 18 years) met a definition of post-COVID-19 condition in March 2022. Specific persisting symptoms such as anxiety or difficulty concentrating were frequently reported regardless of prior infection status and increased with age: 48.0% of primary school pupils, 52.9% of secondary school pupils in years 7-11 and 79.5% in years 12-13 reporting at least one symptom lasting more than 12 weeks. Persisting loss of smell and taste, cardiovascular and some systemic symptoms were more frequently reported by those with a previous positive test.

CONCLUSIONS: We showed that ongoing symptoms were frequently reported by English schoolchildren regardless of SARS-CoV-2 test results and some specific symptoms such as loss of smell and taste were more prevalent in those with a positive test history. Our study emphasises the wide-ranging impacts of the COVID-19 pandemic on the health and wellbeing of children and young people.

PMID:37020190 | DOI:10.1186/s12879-023-08203-1

Ann Biomed Eng. 2023 Apr 5. doi: 10.1007/s10439-023-03193-2. Online ahead of print.

ABSTRACT

Platelet adhesion to blood vessel walls is a key initial event in thrombus formation in both vascular disease processes and prosthetic cardiovascular devices. We extended a deformable multiscale model (MSM) of flowing platelets, incorporating Dissipative Particle Dynamics (DPD) and Coarse-Grained Molecular Dynamics (CGMD) describing molecular-scale intraplatelet constituents and their interaction with surrounding flow, to predict platelet adhesion dynamics under physiological flow shear stresses. Binding of platelet glycoprotein receptor Ibα (GPIbα) to von Willebrand factor (vWF) on the blood vessel wall was modeled by a molecular-level hybrid force field and validated with in vitro microchannel experiments of flowing platelets at 30 dyne/cm². High frame rate videos of flipping platelets were analyzed with a Semi-Unsupervised Learning System (SULS) machine learning-guided imaging approach to segment platelet geometries and quantify adhesion dynamics parameters. In silico flipping dynamics followed in vitro measurements at 15 and 45 dyne/cm² with high fidelity, predicting GPIbα-vWF bonding and debonding processes, distribution of bonds strength, and providing a biomechanical insight into initiation of the complex platelet adhesion process. The adhesion model and simulation framework can be further integrated with our established MSMs of platelet activation and aggregation to simulate initial mural thrombus formation on blood vessel walls.

PMID:37020171 | DOI:10.1007/s10439-023-03193-2

Eur Spine J. 2023 Apr 5. doi: 10.1007/s00586-023-07675-8. Online ahead of print.

ABSTRACT

BACKGROUND: The microsurgical anterior approach to the cervical spine is commonplace. Fewer surgeons perform posterior cervical microsurgical procedures on a routine basis for lack of indication, more bleeding, persistent postoperative neck pain, and risk of progressive misalignment. In comparison, the endoscopic technique is preferentially performed through the posterior approach. Many spine surgeons and even surgeons versed in lumbar endoscopy are often reluctant to consider endoscopic procedures in the cervical spine. We report the results of a surgeon survey to find out why.

METHODS: A questionnaire of 10 questions was sent to spine surgeons by email and chat groups in social media networks including Facebook, WeChat, WhatsApp, and LinkedIn to collect practice pattern data about microscopic and endoscopic spine surgery in the lumbar and cervical spine. The responses were cross-tabulated by surgeons’ demographic data. Pearson Chi-Square measures, Kappa statistics, and linear regression analysis of agreement or disagreement were performed by analyzing the distribution of variances using the statistical package SPSS Version 27.0.

RESULTS: The survey response rate was 39.7%, with 50 of the 126 surgeons who started the survey submitting a completed questionnaire. Of the 50 surgeons, 56.2% were orthopedic, and 42% neurological surgeons. Most surgeons worked in private practice (42%). Another 26% were university-employed, 18% were in private practice affiliated with a university, and the remaining 14% were hospital employed. The majority of surgeons (55.1%) were autodidacts. The largest responding surgeon groups were between 35-44 years (38%) and between 45-54 years of age (34%). Half of the responding surgeons were routinely performing endoscopic cervical spine surgery. The other half did not perform it for the main hurdle of fear of complications (50%). Lack of appropriate mentorship was listed as second most reason (25.4%). More concerns for not performing cervical endoscopic approaches were the perception of lack of technology (20.8%) and suitable surgical indication (12.5%). Only 4.2% considered cervical endoscopy too risky. Nearly a third (30.6%) of the spine surgeons treated over 80% of their cervical spine patients with endoscopic surgeries. Most commonly performed were posterior endoscopic cervical discectomy (PECD; 52%), posterior endoscopic cervical foraminotomy (PECF; 48%), anterior endoscopic cervical discectomy (AECD; 32%), cervical endoscopic unilateral laminotomy for bilateral decompression (CE-ULBD; 30%), respectively.

CONCLUSION: Cervical endoscopic spine surgery is gaining traction among spine surgeons. However, by far most surgeons performing cervical endoscopic spine surgery work in private practice and are autodidacts. This lack of a teacher to shorten the learning curve as well as fear of complications are two of the major impediments to the successful implementation of cervical endoscopic procedures.

PMID:37020150 | DOI:10.1007/s00586-023-07675-8

Biochem Genet. 2023 Apr 5. doi: 10.1007/s10528-023-10371-3. Online ahead of print.

ABSTRACT

The anti-inflammatory adipokine intelectin-1, which is encoded by the ITLN1 gene, is hypothesized to be linked to the pathogenesis of type 2 diabetes (T2DM) and obesity. The purpose of this study was to examine the effect of the ITLN1 gene polymorphism rs2274907 on obesity and T2DM in Turkish adults. The impact of genotype on lipid profiles and serum intelectin levels in the obese and diabetes groups was also investigated. Randomly selected 2266 adults (mean age, 55.0 ± 11.7 years; 51.2% women) participating in the population-based Turkish adult risk factor study were cross-sectionally analyzed. The genotyping of rs2274907 A > T polymorphism was performed by using the hybridization probe based LightSNiP assay in real-time PCR. T2DM were defined using the criteria of the American Diabetes Association. Obesity was described as Body mass index ≥ 30 kg/m². Statistical analyses were used to investigate the association of genotypes with clinical and biochemical measurements. According to findings, there was no vital connection between the rs2274907 polymorphism and obesity, T2DM, or serum intelectin-1 level. The TA+AA carriers had significantly higher triglyceride levels (p = 0.007) compared with the TT carriers in both obese and T2DM women when adjusted for relevant covariates. ITLN1 rs2274907 polymorphism is not correlated with the risk of obesity and T2DM and not affect serum ITLN1 levels in Turkish adults. However, this polymorphism appears to be important in regulating triglyceride levels in obese and diabetic women.

PMID:37020118 | DOI:10.1007/s10528-023-10371-3