Category: Statistics

Zhonghua Yan Ke Za Zhi. 2022 Jul 11;58(7):506-512. doi: 10.3760/cma.j.cn112142-20220113-00013.

ABSTRACT

Objective: To investigate the effect of phacoemulsification on the Berger space (BS). Methods: A prospective cohort study. Patients with cataract who underwent phacoemulsification and intraocular lens implantation in the Department of Ophthalmology, Affiliated Hospital of Nantong University from May 2021 to October 2021 were enrolled. The BS was observed by slit-lamp microscopy and anterior segment optical coherence tomography (AS-OCT) before and 1 month after operation. Intraoperative optical coherence tomography with a 25G optical fiber was performed to observe the BS. The number of eyes with the BS and materials in the BS (MIB) detected perioperatively was counted, and the width of the BS was measured. Statistical analysis was carried out by the Chi-square test, generalized estimating equations, Mann-Whitney U test and binary logistic regression analysis. Results: A total of 119 patients (119 eyes) were included [44 males, 75 females; mean age, (65±12) years]. Preoperatively, the BS was identified in only 4 eyes (3.4%), and no MIB was found. Intraoperatively, the BS was identified in 47 eyes (39.5%), and the MIB was observed in 20 eyes (16.8%). At one month postoperatively, the BS was identified in 33 eyes (27.7%), of which 16 eyes (13.4%) still had MIB. There were significant differences in the detection rates of the BS and MIB between intraoperative and preoperative groups (both P<0.001). The difference in the detection rate of the BS postoperatively compared to intraoperatively was statistically significant (P=0.001), while the difference in the detection rate of MIB was not statistically significant (P>0.05). The intraoperative and postoperative width of the BS [M (Q₁, Q₃)] was 160.3 (61.6, 273.1) μm and 106.8 (0, 259.4) μm, respectively, and the difference was statistically significant (Z=-2.28, P=0.023). In addition, the detection rate of the BS and MIB in patients with a high risk of zonular fiber weakness [60.7% (17/28) and 42.9% (12/28)] was significantly higher than that in patients without this risk factor [33.0% (30/91) and 8.8% (8/91)] (χ²=6.90, P=0.009; P<0.001). In the multivariable model, weakness of zonular fibers (OR=0.214, 95%CI: 0.081 to 0.561) and higher cumulative dissipated energy (OR=1.255, 95%CI: 1.047 to 1.504) were the main risk factors for structural changes of the BS intraoperatively. Conclusion: Phacoemulsification can damage the normal anatomical structure of the BS, resulting in intraoperative entrance of fluid and particulates to the BS.

PMID:35796123 | DOI:10.3760/cma.j.cn112142-20220113-00013

Radiat Oncol J. 2022 Jun;40(2):103-110. doi: 10.3857/roj.2021.00864. Epub 2022 May 25.

ABSTRACT

PURPOSE: This study aims to assess the locoregional efficacy of postoperative vaginal brachytherapy (VBT) alone in patients undergoing surgical staging for early-stage high-intermediate-risk (HIR) and high-risk (HR) endometrial cancer.

MATERIALS AND METHODS: One hundred and four patients with early-stage HIR and HR endometrial cancer who underwent surgical staging were treated with adjuvant VBT alone. The patients with stage Ib, grade I-III, stage Ia, grade III, lower uterine segment involvement, and lymphovascular invasion (LVI) were included to study.

RESULTS: The 5- and 10-year overall survival (OS) rates were 87% and 76%, respectively. The 5- and 10-year DFS rates were 86% and 86%, respectively. Among the patients, 92% had endometrioid adenocarcinoma, 2% had undifferentiated carcinoma, 2% had serous papillary carcinoma, and 4% had clear-cell carcinoma. Of the patients, 63% had stage Ib disease, while 37% had stage Ia disease. None of the patients had vaginal or pelvic lymph node recurrence, whereas two had para-aortic lymph node metastasis, one had surgical scar recurrence, one had para-aortic lymph node and brain metastasis, and one had lung metastasis. The presence of lymphatic invasion was found to be a statistically significant prognostic factor for increased distant metastasis rates (p = 0.020). Lymphatic invasion was also regarded as an independent prognostic factor for metastasis-free survival (p = 0.044).

CONCLUSION: Our study results suggest that postoperative VBT alone is an effective and safe treatment modality with low complication in patients undergoing surgical staging for HIR and HR endometrial cancer.

PMID:35796113 | DOI:10.3857/roj.2021.00864

BJS Open. 2022 Jul 7;6(4):zrac077. doi: 10.1093/bjsopen/zrac077.

ABSTRACT

BACKGROUND: Varicose vein (VV) treatments have changed significantly in recent years leading to potential disparities in service provision. The aim of this study was to examine the trends in VV treatment in England and to identify disparities in the provision of day-case and inpatient treatments related to deprivation, ethnicity, and other demographic, and geographical factors.

METHOD: A population-based study using linked hospital episode statistics for England categorized VV procedures and compared population rates and procedure characteristics by ethnicity, deprivation quintile, and geographical area.

RESULTS: A total of 311 936 people had 389 592 VV procedures between 2006/07 and 2017/18, with a further 63 276 procedures between 2018/19 and 2020/21. Procedure rates have reduced in all but the oldest age groups, whereas endovenous procedures have risen to more than 60 per cent of the total in recent years. In younger age groups there was a 20-30 per cent reduction in procedure rates for the least-deprived compared with the most-deprived quintiles. Non-white ethnicity was associated with lower procedure rates. Large regional and local differences were identified in standardized rates of VV procedures. In the most recent 5-year interval, the North-East region had a three-fold higher rate than the South-East region with evidence of greater variation between commissioners in overall rates, the proportion of endovenous procedures, and policies regarding bilateral treatments.

CONCLUSIONS: There are substantial geographical variations in the provision of treatment for VVs, which are not explained by demographic differences. These have persisted, despite the publication of guidelines from the National Institute for Health and Care Excellence, and many commissioners, and providers would seem to implement policies that are contrary to this guidance. Lower rates of procedures in less-deprived areas may reflect treatments carried out in private practice, which are not included in these data.

PMID:35796069 | DOI:10.1093/bjsopen/zrac077

J Exp Biol. 2022 Jul 7:jeb.244471. doi: 10.1242/jeb.244471. Online ahead of print.

ABSTRACT

The U-shaped net cost of transport (COT) curve of walking has helped scientists understand the biomechanical basis that underlies energy minimization during walking. However, to produce an individual’s net COT curve, data must be analyzed during periods of steady-rate metabolism. Traditionally, studies analyze the last few minutes of a 6-10 min trial, assuming that steady-rate metabolism has been achieved. Yet, it is possible that an individual achieves steady rates of metabolism much earlier. However, there is no consensus on how to objectively quantify steady-rate metabolism across a range of walking speeds. Therefore, we developed a simple slope method to determine the minimum time needed for humans to achieve steady rates of metabolism across slow to fast walking speeds. We hypothesized that a shorter time window could be used to produce a net COT curve that is comparable to the net COT curve created using traditional methods. We analyzed metabolic data from twenty-one subjects who completed several 7-min walking trials ranging from 0.50-2.00 m/s. We partitioned the metabolic data for each trial into moving 1-min, 2-min, and 3 min intervals and calculated their slopes. We statistically compared these slope values to values derived from the last 3-min of the 7-min trial, our ‘gold’ standard comparison. We found that a minimum of 2 min is required to achieve steady-rate metabolism and that data from 2-4 min yields a net COT curve that is not statistically different from the one derived from experimental protocols that are generally accepted in the field.

PMID:35796105 | DOI:10.1242/jeb.244471

Nurse Res. 2022 Jul 7. doi: 10.7748/nr.2022.e1835. Online ahead of print.

ABSTRACT

BACKGROUND: Self-administered questionnaires are efficient and low-cost ways of collecting data with wide cohorts. Nonetheless, their use in studies can result in a high occurrence of missing data, which can affect the statistical power, representativeness and generalisability of the findings. Imputation methods have been considered efficient statistical techniques for managing missing data. However, they have also been associated with limits, such as the risk of under-estimation of the effect, lower statistical power and decrease of correlation among variables. Recent studies have highlighted the importance of using prevention strategies to avoid missing data before the data are analysed.

AIM: To identify strategies for preventing the occurrence of missing data and to discuss their effects, as well as their methodological and statistical considerations.

DISCUSSION: The article discusses prevention strategies related to the administration format and follow-up and reminders. Strategies such as the use of electronic tablets, email and telephone reminders are associated with lower rates of missing data in self-administered questionnaires. However, methodological and statistical limits, including the absence of a comparison group and statistical validation of the reported results, limits the capacity to establish robust consensus.

CONCLUSION: Prevention strategies represent relevant and feasible avenues for handling missing data in a wide range of clinical, nursing and epidemiological research. More projects based on robust design are needed to ensure accurate and reliable data are collected from patients, families, communities and clinicians.

IMPLICATIONS FOR PRACTICE: It is important for clinicians and nurses to understand the phenomenon of missing data and the strategies available to prevent missing data, to collect data representing the patients’ and families’ perspectives and experiences.

PMID:35796061 | DOI:10.7748/nr.2022.e1835

Elife. 2022 Jul 7;11:e72602. doi: 10.7554/eLife.72602.

ABSTRACT

Analysis of the content of medical journals enables us to frame the shifting scientific, material, ethical, and epistemic underpinnings of medicine over time, including today. Leveraging a dataset comprised of nearly half-a-million articles published in the Journal of the American Medical Association (JAMA) and the New England Journal of Medicine (NEJM) over the past 200 years, we (a) highlight the evolution of medical language, and its manifestations in shifts of usage and meaning, (b) examine traces of the medical profession’s changing self-identity over time, reflected in its shifting ethical and epistemic underpinnings, (c) analyze medicine’s material underpinnings and how we describe where medicine is practiced, (d) demonstrate how the occurrence of specific disease terms within the journals reflects the changing burden of disease itself over time and the interests and perspectives of authors and editors, and (e) showcase how this dataset can allow us to explore the evolution of modern medical ideas and further our understanding of how modern disease concepts came to be, and of the retained legacies of prior embedded values.

PMID:35796055 | DOI:10.7554/eLife.72602

Clin Exp Dent Res. 2022 Jul 7. doi: 10.1002/cre2.623. Online ahead of print.

ABSTRACT

OBJECTIVES: Dental implants are a known treatment today. It is necessary to have at least 2 mm of bone around the implant, especially in the buccal aspect of the anterior maxilla (esthetic zone). Some systemic conditions, such as menopause, can affect the body’s bone mass as well as the alveolar bone. Considering that few studies have been carried out on the effect of menopause on the thickness and topography of alveolar bone, we decided to investigate the effect of menopause on buccal alveolar bone thickness in the anterior maxillary teeth in menopausal women. MATERIAL AND METHODS: In this descriptive-analytical cross-sectional study, two subgroups of menopausal women and nonmenopausal women were considered. Data were extracted from 30 patients referred to a private radiology center in Mashhad for CBCT imaging. In addition, the buccal bone thickness in the crest and middle areas of the anterior maxillary teeth was measured and the difference between the two groups was investigated. The buccal bone thickness of the aesthetic area was evaluated with CBCT Planmeca ProMax 3D Max (Planmeca) by Planmeca Romexis 5.3.4 software, with 200 μm Voxel size and Fov 90 × 60 mm.

RESULTS: In this study, 30 women with a mean age of 49.75 ± 3.65 years in the nonmenopausal and menopausal groups were examined. It was found that the mean buccal bone thickness of the anterior maxilla in the nonmenopausal group (0.65 ± 0.25 mm) was higher than in the menopausal group (0.56 ± 0.20 mm), but the difference was not statistically significant (p = .2999). Only in the crestal bone of the right canine, the average bone thickness in nonmenopausal group (0.77 ± 0.33 mm) was significantly higher than the menopausal group (0.49 ± 0.22 mm) (p = .011).

CONCLUSIONS: Owing to changes in the volume and thickness of alveolar bone in menopausal women, the thickness of the buccal bone in the aesthetic area decreases, but this is not statistically significant.

PMID:35796053 | DOI:10.1002/cre2.623

Immunotherapy. 2022 Jul 7. doi: 10.2217/imt-2022-0082. Online ahead of print.

ABSTRACT

Objective: This study evaluated the cost-effectiveness of pembrolizumab/chemotherapy combinations for previously untreated metastatic triple-negative breast cancer patients in the USA with PD-L1 combined positive score ≥10. Methods: A partitioned-survival model was developed to project health outcomes and direct medical costs over a 20-year time horizon. Efficacy and safety data were from randomized clinical trials. Comparative effectiveness of indirect comparators was assessed using network meta-analyses. A series of sensitivity analyses were performed to test the robustness of the results. Results: Pembrolizumab/chemotherapy resulted in total quality-adjusted life-year (QALY) gains of 0.70 years and incremental cost-effectiveness ratio of US$182,732/QALY compared with chemotherapy alone. The incremental cost-effectiveness ratio for pembrolizumab/nab-paclitaxel versus atezolizumab/nab-paclitaxel was US$44,157/QALY. Sensitivity analyses showed the results were robust over plausible values of model inputs. Conclusion: Pembrolizumab/chemotherapy is cost effective compared with chemotherapy as well as atezolizumab/nab-paclitaxel as first-line treatment for PD-L1-positive metastatic triple-negative breast cancer from a US payer perspective.

PMID:35796042 | DOI:10.2217/imt-2022-0082

Psychol Med. 2022 Jul 7:1-13. doi: 10.1017/S003329172200160X. Online ahead of print.

ABSTRACT

BACKGROUND: While adolescent-onset schizophrenia (ADO-SCZ) and adolescent-onset bipolar disorder with psychosis (psychotic ADO-BPD) present a more severe clinical course than their adult forms, their pathophysiology is poorly understood. Here, we study potentially state- and trait-related white matter diffusion-weighted magnetic resonance imaging (dMRI) abnormalities along the adolescent-onset psychosis continuum to address this need.

METHODS: Forty-eight individuals with ADO-SCZ (20 female/28 male), 15 individuals with psychotic ADO-BPD (7 female/8 male), and 35 healthy controls (HCs, 18 female/17 male) underwent dMRI and clinical assessments. Maps of extracellular free-water (FW) and fractional anisotropy of cellular tissue (FA_T) were compared between individuals with psychosis and HCs using tract-based spatial statistics and FSL’s Randomise. FA_T and FW values were extracted, averaged across all voxels that demonstrated group differences, and then utilized to test for the influence of age, medication, age of onset, duration of illness, symptom severity, and intelligence.

RESULTS: Individuals with adolescent-onset psychosis exhibited pronounced FW and FA_T abnormalities compared to HCs. FA_T reductions were spatially more widespread in ADO-SCZ. FW increases, however, were only present in psychotic ADO-BPD. In HCs, but not in individuals with adolescent-onset psychosis, FA_T was positively related to age.

CONCLUSIONS: We observe evidence for cellular (FA_T) and extracellular (FW) white matter abnormalities in adolescent-onset psychosis. Although cellular white matter abnormalities were more prominent in ADO-SCZ, such alterations may reflect a shared trait, i.e. neurodevelopmental pathology, present across the psychosis spectrum. Extracellular abnormalities were evident in psychotic ADO-BPD, potentially indicating a more dynamic, state-dependent brain reaction to psychosis.

PMID:35796024 | DOI:10.1017/S003329172200160X

Brief Bioinform. 2022 Jul 6:bbac259. doi: 10.1093/bib/bbac259. Online ahead of print.

ABSTRACT

In 2014, the Immune Epitope Database automated benchmark was created to compare the performance of the MHC class I binding predictors. However, this is not a straightforward process due to the different and non-standardized outputs of the methods. Additionally, some methods are more restrictive regarding the HLA alleles and epitope sizes for which they predict binding affinities, while others are more comprehensive. To address how these problems impacted the ranking of the predictors, we developed an approach to assess the reliability of different metrics. We found that using percentile-ranked results improved the stability of the ranks and allowed the predictors to be reliably ranked despite not being evaluated on the same data. We also found that given the rate new data are incorporated into the benchmark, a new method must wait for at least 4 years to be ranked against the pre-existing methods. The best-performing tools with statistically indistinguishable scores in this benchmark were NetMHCcons, NetMHCpan4.0, ANN3.4, NetMHCpan3.0 and NetMHCpan2.8. The results of this study will be used to improve the evaluation and display of benchmark performance. We highly encourage anyone working on MHC binding predictions to participate in this benchmark to get an unbiased evaluation of their predictors.

PMID:35794711 | DOI:10.1093/bib/bbac259