The effect of different statistical approaches on image quality data obtained from radiological examinations

IntroductionSelection of optimal image acquisition protocols in medical imaging remains a grey area, the superimposed use of the Likert scale in radiological image quality evaluations creates an additional challenge for the statistical analysis of image quality data.Using a simulation study, we have trialled a novel approach to analysing radiological image quality Likert scale data.MethodsA simulation study was undertaken where simulated datasets were generated based on the distribution of Likert scale values according to varying image acquisition protocols from a real dataset. Simulated Likert scale values were pooled in four different ways; the mean, median, mode and the summation of patient Likert scale values of which the total was assigned a categorical Likert scale value. Estimates of bias, MAPE and RMSPE were then calculated for all four pooling approaches to determine which method most accurately represented an expert's opinion.ResultsWhen compared to an expert's opinion, the method of summation and categorisation of Likert scale values was most accurate 49 times out of the 114 (43.0%) tests. The mean 28 times out of 114 (24.6%), the median 23 times out of 114 (20.2%) and the mode 17 times out of 114 (14.9%).ConclusionWe conclude that our method of summation and categorisation of Likert scale values is most often the best representation of the simulated data compared to the expert's opinion.Implications for practiceThere is scope to reproduce this simulation study with multiple observers to reflect clinical reality more accurately with the dynamic nature of multiple observers. This also prompts future investigation into other anatomical areas, to see if the same methods produce similar results.     

多层螺旋CT定量评估慢性阻塞性肺疾病病情的价值

目的探讨多层螺旋CT(MSCT)定量评估慢性阻塞性肺疾病病情的价值。方法选取2017年8月～2018年7月在湖州市第一人民医院就诊的73例慢性阻塞性肺疾病(COPD)患者作为研究对象,按照病情轻重分为Ⅰ组(轻度患者17例)、Ⅱ组(中度患者32例)、Ⅲ组(重度患者24例),并选取同期于该院体检的健康者20例为对照组。所有研究对象均行MSCT低剂量扫描,观察比较各组管腔面积(Ai)、支气管壁面积百分比(WA%)、管壁厚度与体表面积比值(T/BSA)、壁厚度与直径比值(TDR),同时予以肺功能检查,采用定量CT气道分析软件分别测量气道相关参数,并用Siemens Pulmo软件Pearson定量分析其相关性。结果对照组、Ⅰ组、Ⅱ组、Ⅲ组的FEV1均呈逐渐下降趋势,FEV1/FVC呈逐渐上升趋势,差异均有统计学意义(P0.05)。对照组、Ⅰ组、Ⅱ组、Ⅲ组的WA%、T/BSA、TDR比较,均呈逐渐上升趋势,Ai呈下降趋势,差异均有统计学意义(P0.05)。FEV1与WA%、TDR之间呈负相关(r=-0.291,P=0.000;r=-0.473,P=0.000),FEV1/FVC与WA%、TDR之间呈正相关(r=0.285,P=0.000;r=0.472,P=0.000)。结论 MSCT扫描及定量分析可为COPD患者气道病变情况提供可靠的评估信息。     

步行量和体成分的中日比较研究

目的 为了解中日儿童及成人的步行和体成分及其相互关系.方法 以中国上海市和日本琦玉县的小学生和成人为对象,采用西铁城 TW02-001电子式步数计测定步行量,FUTREX-5000A体成分测定仪测量体脂百分比.结果 1.中国男女小学生的平均每日步行量分别为12426步和10387步,低于日本小学生(男15 340步,女11 617步),体脂百分比中国男女生分别为21.2%和15.8%,高于日本(男18.9%,女13.1%).中国男女成人的平均每日步行量分别为9826步和8748步,高于日本成人(男:8411步,女7599步);体脂百分比分别为17.5%(男)和25.8%(女),而日本男性为19.8%,女性为26.0%.2.不同活动水平的小学生和成人,其血压和体成分均有差异,步行量高者的血压和体脂百分比都较低.本研究还计算出以肱三头肌皮脂厚度以(X)推测儿童体脂百分比(Y)的回归方程为:Y=10.6646+0.5856X.结论 作为日常生活的步行可促进肥胖发生率的降低.     

Favourable associations between the myosin heavy-chain and light-chain isoforms in human skeletal muscle

Histochemical and biochemical analyses were performed in order to examine the relationship between myosin light-chain (LC) isoforms and fibre-type distributions in whole human skeletal muscle. Muscle biopsies were obtained from the vastus lateralis muscle in six healthy men, and analysed for the relative area occupied by each fibre type (percentage of fibre type area) and the molar ratio of each LC isoform. The percentage of type I fibre area was positively correlated with the molar ratio of slow LC (LC1s and LC2s) to total LC. The regression line was located below the line of unity. Also, the ratio of percentage of type II fibre area to that of type II fibre area was positively correlated with the molar ratio of the fast alkali LC LC1f to fast alkali LCs LC1f and LC3f. These results support previous study, having shown that in human skeletal muscle some type I fibres express various amounts of fast LC in addition to slow LC and suggest that fast myosin heavy-chain HCII a is favourably associated with LC1f, whereas HCIIb is favourably associated with LC3f.     

相似系数法在川贝母群落分类中的应用研究

目的　探讨数值分类方法应用于川贝母分布群落类型的划分。方法　以群落相似系数百分率划分川贝母分布的群落类型。结论　应用相似系数法可将川贝母野生抚育的适宜群落划定为窄叶鲜卑花灌丛、理塘杜鹃灌丛、硬叶柳灌丛、金露梅 +绣线菊灌丛、香柏灌丛、珠芽蓼 +圆穗蓼草甸等 6种类型     

Supplementary formulas and tables for calculating and interconverting speech recognition scores in transformed arcsine units

Formulas that convert speech recognition scores, in percent or proportions, into units based on the arcsine transform have been described previously. This report reviews that work and presents various supplementary equations and tables for calculating and interconverting the proposed units. The relative merits of these data and their application to scores from closed-set tests are also discussed.     

Predicting healthcare expenditure by multimorbidity groups

Objectives

This article has two main purposes. Firstly, to model the integrated healthcare expenditure for the entire population of a health district in Spain, according to multimorbidity, using Clinical Risk Groups (CRG). Secondly, to show how the predictive model is applied to the allocation of health budgets.

Sex-discrete role of depressive symptomatology on 10-year first and recurrent cardiovascular disease incidence: results from ATTICA and GREECS prospective studies

ObjectiveThe sex-specific effect of depressive symptomatology on 10-year first and recurrent cardiovascular disease (CVD) events was evaluated.MethodsThe Greek samples from ATTICA (2002-2012, n = 845 free-of-CVD subjects) and GREECS (2004-2014, n = 2,172 subjects with acute coronary syndrome (ACS)) prospective epidemiological studies with baseline psychological assessments were used for the first and the recurrent event, respectively. Depressive symptomatology was assessed at baseline, through Zung Self-Rating Depression Scale in the ATTICA study, and through the Center for Epidemiological Studies-Depression scale in the GREECS study.ResultsACS as well as free-of-CVD women scored significantly higher for depressive symptomatology. Men scored higher than women against first (19.7% vs. 11.7%) and subsequent CVD events (38.8% vs. 32.9%). In participants with depressive symptoms man-to-woman first and recurrent CVD event rate ratio was below 1, confirming that depressive women were more likely to have a CVD event than depressive men. Multiadjusted analysis revealed that depressive symptomatology had an independent aggravating effect on the first (hazard ratio (HR) = 2.72, 95% confidence interval (95% CI) 1.50, 9.12) and recurrent (HR = 1.31, 95% CI 1.01, 1.69) CVD events only in women. Mediation analysis in women revealed that 35% (23%, 44%) of excess first-CVD-event risk of depressive symptoms was attributed to conventional risk factors. The respective number for recurrent CVD events was 46% (23%, 53%); different patterns of ranking regarding the mediating effect corresponding to each adjustment factor were observed.ConclusionsThe present work augments prior evidence that psychological stressors possess important drivers of CVD onset and progression mainly in women, while it gives rise to research toward unidentified paths behind this claim.     

Long term weight maintenance after advice to consume low carbohydrate,higher protein diets – A systematic review and meta analysis

BackgroundMeta analysis of short term trials indicates that a higher protein, lower carbohydrate weight loss diet enhances fat mass loss and limits lean mass loss compared with a normal protein weight loss diet. Whether this benefit persists long term is not clear.Methods and resultsWe selected weight loss studies in adults with at least a 12 month follow up in which a higher percentage protein/lower carbohydrate diet was either planned or would be expected for either weight loss or weight maintenance. Studies were selected regardless of the success of the advice but difference in absolute and percentage protein intake at 12 months was used as a moderator in the analysis. Data was analysed using Comprehensive Meta analysis V2 using a random effects analysis. As many as 32 studies with 3492 individuals were analysed with data on fat and lean mass, glucose and insulin from 18 to 22 studies and lipids from 28 studies. A recommendation to consume a lower carbohydrate, higher protein diet in mostly short term intensive interventions with long term follow up was associated with better weight and fat loss but the effect size was small-standardised means of 0.14 and 0.22, p = 0.008 and p < 0.001 respectively (equivalent to 0.4 kg for both). A difference of 5% or greater in percentage protein between diets at 12mo was associated with a 3 fold greater effect size compared with <5% (p = 0.038) in fat mass (0.9 vs. 0.3 kg). Fasting triglyceride and insulin were also lower with high protein diets with effect sizes of 0.17 and 0.22, p = 0.003 and p = 0.042 respectively. Other lipids and glucose were not different.ConclusionThe short term benefit of higher protein diets appears to persist to a small degree long term. Benefits are greater with better compliance to the diet.     

Global burden attributable to high sodium intake from 1990 to 2019

Background and aimsHigh sodium intake is associated with a higher risk of a wide range of diseases. We aimed to estimate the pattern and trend of the global disease burden associated with high sodium intake from 1990 to 2019.Methods and resultsWe obtained numbers and rates of death and disability-adjusted life year (DALY) attributable to high sodium intake by sex, socio-demographic index, and country from the Global Burden of Disease Study 2019. We calculated the estimated annual percentage change to evaluate the age-standardized rate (ASR) of the burden attributable to high sodium intake between 1990 and 2019. We further calculated the contribution of population growth, population aging, and age-specific rates of death and DALY to the net change in the total number of deaths and DALYs attributable to high sodium intake. From 1990 to 2019, global age-standardized rates of death and DALY attributable to high sodium intake substantially decreased for both sexes. However, there were significant increases in the total numbers of deaths and DALYs attributable to high sodium intake, which were driven by population growth and population aging. The attribution of population growth and population aging varied widely across countries, with a higher contribution of population growth in most developing countries and a higher contribution of population aging in countries with slow population growth.ConclusionsAlthough the global burden attributable to high sodium intake in terms of age-standardized rate declined from 1990 to 2019, the absolute burden increased significantly, which was driven by population growth and population aging.