External validation and newly development of a nomogram to predict overall survival of abiraterone-treated, castration-resistant patients with metastatic prostate cancer

Abiraterone acetate is approved for the treatment of castration-resistant prostate cancer （CRPC）; however, its effects vary. An accurate prediction model to identify patient groups that will benefit from abiraterone treatment is therefore urgently required. The Chi model exhibits a good profile for risk classification, although its utility for the chemotherapy-naive group is unclear. This study aimed to externally validate the Chi model and develop a new nomogram to predict overall survival （OS）. We retrospectively analyzed a cohort of 110 patients. Patients were distributed among good-, intermediate-, and poor-risk groups, according to the Chi model. The good-, intermediate-, and poor-risk groups had a sample size of 59 （53.6%）, 34 （30.9%）, and 17 （15.5%） in our dataset, and a median OS of 48.4, 29.1, and 10.5 months, respectively. The C-index of external validation of Chi model was 0.726. Univariate and multivariate analyses identified low hemoglobin concentrations （〈110 g l^-1）, liver metastasis, and a short time interval from androgen deprivation therapy to abiraterone initiation （〈36 months） as predictors of OS. Accordingly, a new nomogram was developed with a C-index equal to 0.757 （95% CI, 0.678-0.836）. In conclusion, the Chi model predicted the prognosis of abiraterone-treated, chemotherapy-naive patients with mCRPC, and we developed a new nomogram to predict the overall survival of this group of patients with less parameters.

Development and validation of a questionnaire-based risk scoring system to identify individuals at high risk for gastric cancer in Chinese populations

Objective:This study aimed to develop and validate a risk scoring system to identify high-risk individuals carrying malignant lesions in stomach for tailored gastric cancer screening.Methods:A gastric cancer risk scoring system(GC-RSS)was developed based on questionnaire-based predictors for gastric cancer derived from systematic literature review.To assess the capability of this system for discrimination,risk scores for 8,214 and 7,235 outpatient subjects accepting endoscopic examination in two endoscopy centers,and 32,630 participants in a community-based cohort in China were calculated to plot receiver operating characteristic curves and generate area under the curve(AUC).To evaluate the performance of GC-RSS,the screening proportion,sensitivity and detection rate ratio compared to universal screening were used under different risk score cutoff values.Results:GC-RSS comprised nine predictors including advanced age,male gender,low body mass index(<18.5 kg/m^(2)),family history of gastric cancer,cigarette smoking,consumption of alcohol,preference for salty food,irregularity of meals and consumption of preserved food.This tool performed well in determining the risk of malignant gastric lesions with AUCs of 0.763,0.706 and 0.696 in three validation sets.When subjects with risk scores≥5 were evaluated with endoscopy,nearly 50%of these endoscopies could be saved with a detection rate of over 1.5 times achieved.When the cutoff was set at 8,only about 10%of subjects with the highest risk would be offered endoscopy,and detection rates for gastric cancer could be increased 2-4 fold compared to universal screening.Conclusions:An effective questionnaire-based GC-RSS was developed and validated.This tool may play an important role in establishing a tailored screening strategy for gastric cancer in China.

Simulated patient methodology as a“gold standard”in community pharmacy practice:Response to criticism

The simulated patient methodology(SPM)is considered the“gold standard”as covert participatory observation.SPM is attracting increasing interest for the investigation of community pharmacy practice;however,there is criticism that SPM can only show a small picture of everyday pharmacy practice and therefore has limited external validity.On the one hand,a certain design and application of the SPM goes hand in hand with an increase in external validity.Even if,on the other hand,this occurs at the expense of internal validity due to the trade-off situation,the justified criticism of the SPM for investigating community pharmacy practice can be countered.

A validation study of southern China for European prediction model about ventricular arrhythmias for arrhythmogenic right ventricular cardiomyopathy

Background Arrhythmogenic right ventricular dysplasia/cardiomyopathy is an inherited cardiomyopathy.European Society of Cardiology was devised a new prediction model to estimate ventricular arrhythmias and guide decisions regarding primary prevention ICDs.This paper aimed to conduct external validation of European prediction model in the South China.

Comparison of various prediction models in the effect of laparoscopic sleeve gastrectomy on type 2 diabetes mellitus in the Chinese population 5 years after surgery

Background:The effect of bariatric surgery on type 2 diabetes mellitus(T2DM)control can be assessed based on predictive models of T2DM remission.Various models have been externally verified internationally.However,long-term validated results after laparoscopic sleeve gastrectomy(LSG)surgery are lacking.The best model for the Chinese population is also unknown.Methods:We retrospectively analyzed Chinese population data 5 years after LSG at Beijing Shijitan Hospital in China between March 2009 and December 2016.The independent t-test,Mann–Whitney U test,and chi-squared test were used to compare characteristics between T2DM remission and non-remission groups.We evaluated the predictive efficacy of each model for longterm T2DM remission after LSG by calculating the area under the curve(AUC),sensitivity,specificity,Youden index,positive predictive value(PPV),negative predictive value(NPV),and predicted-to-observed ratio,and performed calibration using Hosmer–Lemeshow test for 11 prediction models.Results:We enrolled 108 patients,including 44(40.7%)men,with a mean age of 35.5 years.The mean body mass index was 40.3±9.1 kg/m^(2),the percentage of excess weight loss(%EWL)was(75.9±30.4)%,and the percentage of total weight loss(%TWL)was(29.1±10.6)%.The mean glycated hemoglobin A1c(HbA1c)level was(7.3±1.8)%preoperatively and decreased to(5.9±1.0)%5 years after LSG.The 5-year postoperative complete and partial remission rates of T2DM were 50.9%[55/108]and 27.8%[30/108],respectively.Six models,i.e.,"ABCD",individualized metabolic surgery(IMS),advanced-DiaRem,DiaBetter,Dixon et al’s regression model,and Panunzi et al’s regression model,showed a good discrimination ability(all AUC>0.8).The"ABCD"(sensitivity,74%;specificity,80%;AUC,0.82[95%confidence interval[CI]:0.74–0.89]),IMS(sensitivity,78%;specificity,84%;AUC,0.82[95%CI:0.73–0.89]),and Panunzi et al’s regression models(sensitivity,78%;specificity,91%;AUC,0.86[95%CI:0.78–0.92])showed good discernibility.In the Hosmer–Lemeshow goodness-of-fit test,except for DiaRem(P<0.01),DiaBetter(P<0.01),Hayes et al(P=0.03),Park et al(P=0.02),and Ramos-Levi et al’s(P<0.01)models,all models had a satifactory fit results(P>0.05).The P values of calibration results of the"ABCD"and IMS were 0.07 and 0.14,respectively.The predicted-to-observed ratios of the"ABCD"and IMS were 0.87 and 0.89,respectively.Conclusion:The prediction model IMS was recommended for clinical use because of excellent predictive performance,good statistical test results,and simple and practical design features.

Modeling method for SSC prediction in pomelo using Vis-NIRS with wavelength selection and latent variable updating

The aim of this study was in-line,rapid,and non-destructive detection for soluble solid content(SSC)in pomelos using visible and near-infrared spectroscopy(Vis-NIRS).However,the large size and thick rind of pomelo affect the stability of spectral acquisition and the biological variabilities affect the robustness of models.Given these issues,in this study,an efficient prototype in-line detection system in transmittance mode was designed and evaluated in comparison with an off-line detection system.Data from the years 2019 and 2020 were used for modeling and the external validation data were obtained by the inline detection system in 2021.The wavelength selection methods of changeable size moving window(CSMW),random frog(RF),and competitive adaptive reweighted sampling(CARS)were used to improve the prediction accuracy of partial least squares regression(PLSR)models.The best performance of internal prediction was obtained by CARS-PLSR and the determination coefficient of prediction(),root mean square error of prediction(RMSEP),and residual predictive deviation(RPD)were 0.958,0.204%,and 4.821,respectively.However,all models obtained large prediction biases in external validation.The latent variable updating(LVU)method was proposed to update models and improve the performance in external validation.Ten samples from the external validation set were randomly selected to update the models.Compared with the recalibration method,LVU could effectively modify the original models which matched the SSC range of the external validation set.The CSMW-PLSR models were more robust in external validations.The off-line model with LVU performed best with a root mean square error of validation(RMSEV)of 0.599%and the in-line model with recalibration obtained RMSEV of 0.864%.These results demonstrated the application potential of the transmittance Vis-NIRS for in-line rapid prediction of SSC in pomelos and the modeling and updating methods could be applied to samples with biological variabilities.

How to Connect the Gap between Clinical Trials and Clinical Practice

Clinical research methods have been rapidly developing, and the design of clinical trials including traditional Chinese medicine is advancing. To a certain extent, all of these ensure that the results of clinical research are objective and scientific, but whether these results and the resulting guidelines or consensus have much practical significance on clinical practice is still controversial. The authors engage in both clinical practice and clinical research; they strongly feel that it is necessary to discuss the relationship between clinical trials and clinical practice. This essay discusses this relationship in four parts.

Methodological Considerations Which Could Improve Spinal Cord Injury Research

Advances in spinal cord injury-based research in the last 50 years have resulted in significant improvements to therapy options.However,the efficacy of such research could be further enhanced if threats to internal and external validity were addressed.To provide perspective,a sample topic was identified:the effects of acute and chronic exercise on clinical and sub-clinical markers of cardiovascular health.The intention was not a systematic review,nor a critique of exercise-based research,but rather a means to generate further discussion.Thirty-one articles were identified,and four common issues were found relating to:(1)sampling;(2)study design;(3)control group;and(4)clinical inference.These concerns were largely attributed to insufficient resources,and challenges associated with recruiting individuals with spinal cord injury.Overcoming these challenges will be difficult,but some opportunities include:(1)implementing multi-center trials;(2)sampling from subject groups appropriate to the research question;(3)including an appropriate control group;and(4)clearly defining clini-cal inference.These opportunities are not always feasible,and some easier to implement than others.However,addressing these concerns may assist in progressing spinal cord injury-based research,thereby helping to ensure steady advancement of therapy options for persons with spinal cord injury.