Objective To investigate the sensitivity of 5 kinds of chemotherapeutic drugs on human colorectal cancer in vivo. Methods Xenografts in nude mice were set up by tumor tissues from 9 patients with colorectal cancer and nude mice were divided into 6 groups randomly， receiving saline （control group）， 5-fluorouracil （5-FU group）， doxorubicin（ADM group）， mitomycin （MMC group）， oxaliplatin （LOHP group）， and irinotecan （CPT-11 group）， respectively. The inhibitive rates （IR） of xenografts in 5 groups for each patient were calculated. Results The lowest and highest IR of 5 groups were 23.6% and 54.9% in 5-FU group， 23.7% and 69.5% in LOPH group， 23.6% and 82.6% in CPT-11group， 24.1% and 48.1% in MMC group， 5.8% and 20.7% in ADM group， respectively. The IR exceeded 40.0% in 7 patients of LOHP group， 6 patients of CPT-11 group， 4 patients of 5-FU group， and 1 patient of MMC group， respec-tively. Of 9 patients， the IR exceeded 40.0% to 3 kinds of drugs in 3 patients， to 2 kinds of drugs in 4 patients， the IR didn’t exceed 30.0% to 4 kinds of drug （IR was 82.6% to CPT-11） in 1 patient， and the IR didn’t exceed 31.0% to all 5 kinds of drugs in 1 patient. There were statistical differences on the IR of 5 kinds of drugs （H=24.061 2， P=0.000 1）. IR of ADM group was statistical lower than 5-FU group， MMC group， LOHP group， and CPT-11 group （P＜0.05），but there were no statistical differences between 5-FU group， MMC group， LOHP group， and CPT-11 group （P＞0.05）. Conclusions The xenografts from same patient have different sensitivity to different chemotherapy drugs， and the same chemotherapy drug corresponds to different IR in different patients. The IR of LOHP and CPT-11 are the highest， following by 5-FU and MMC.
Objective To explore the safety of neoadjuvant chemoradiotherapy combined with sphincter-preserving operation in treatment of locally advanced low rectal cancer. Methods The clinical data of thirty-four patients admitted into our hospital between June 2007 and June 2009 with T3 and T4 low rectal cancer treated by neoadjuvant chemoradiotherapy and sphincter-preserving operation were collected and analyzed retrospectively. Routine fraction of radiation was given with total dose of 40 Gy, five times a week, 2 Gy per fraction. Patients received oxaliplatin （150 mg/d1）, plus folinic (100 mg/d1-3) and 5FU (750 mg/d1-3) for total 1 cycles started from the 4th week of irradiation. Operation was performed 4 weeks after neoadjuvant therapy. Results After neoadjuvant therapy, all patients underwent surgical resection with average tumor size decreased by 41.2%, tumor T stage decreased in 67.6% （23/34) patients, and lymph nodenegative change rate was 58.8% (10/17). One patient had liver metastasis and one had local recurrence, but without stomal leak. And 88.2% (30/34) patients showed good function of sphincter. Conclusions Neoadjuvant chemoradiotherapy in advanced lower rectal cancer patients has shown its efficacy in down-staging, which is safe without increasing operation complications when combined with sphincterpreserving surgery.
Sample size calculation is an important factor to evaluate the reliability of the diagnostic test. In this paper, a case study of the clinical diagnostic test of artificial intelligence for identification of liver contrast-enhanced ultrasound was performed to conduct two-category and multi-categories studies. Based on sensitivity and specificity, the sample size was then estimated in combination with the statistical characteristics of disease incidence, test level and one/two-sided test. Eventually, the sample size was corrected by integrating the factors of the proportion of training/test dataset and the dropout rate of cases in the medical image recognition system. Moreover, the application of Sample Size Calculator, MedCalc, PASS, and other software can accelerate sample size calculation and reduce the amount of labor.
The sensitivity and accuracy of the retrieval results directly affect the results in the systematic review of biomedical researchers. However, different retrieval methods and retrieval tools lead to different retrieval results. In this paper, we first evaluate the effects of Boolean logic retrieval, hierarchical retrieval, topic retrieval and full-text retrieval on the retrieval results of systematic reviews. We then introduce the application of one-stop search tool (Google Scholar and resource discovery system) in systematic review, and compare the effects of different one-stop search tools.
ObjectiveTo introduce sensitivity and homogeneity tests in network meta-analysis and its implementation in R software. MethodsUsing an example, we performed sensitivity analysis by comparing the random effect model with the fixed effect model. Homogeneity analysis was performed using metaphor package and combinat package in R software. ResultsThe results of the two models were similar, and the data was steady. The results of homogeneity analysis showed that the confidential intervals in all loops were crossed over with blank value; and direct and indirect estimates of the effects in network meta-analysis were not significantly different, with good homogeneity. ConclusionNetwork meta-analysis is a kind of indirect comparison analysis method, and its sensitivity is especially important. The introduction of homogeneity makes network meta-analysis more accurate. Using R software for sensitivity and homogeneity analysis in network meta-analysis is a feasible method.
The correct and reasonable statistical analysis method can make the results of comparative diagnosis test accuracy more convincing. In this paper, the accuracy of diagnostic tests is divided into 2 forms: binary-scale outcomes and ordinal-scale/continuous-scale outcomes. Taking diagnostic indicators such as sensitivity, specificity, receiver operating characteristic (ROC) curves and area under curve (AUC) values as entry points, combined with examples, this paper introduced how to compare the diagnostic results of tests by parameter estimation and hypothesis testing, with the aim of providing references for the comparative diagnosis test accuracy.
To perform a meta-analysis of single nucleotide polymorphism needs to calculate gene frequency. This paper employs allele model as an example to introduce how to calculate gene frequency and display the process of a meta-analysis of single nucleotide polymorphism data using Review Manager 5.3 software.
Survival data were widely used in oncology clinical trials. The methods used, such as the log-rank test and Cox regression model, should meet the assumption of proportional hazards. However, the survival data with non-proportional hazard (NPH) are also quite usual, which will decrease the power of these methods and conceal the true treatment effect. Therefore, during the trial design, we need to test the proportional hazard assumption and plan different analysis methods for different testing results. This paper introduces some methods that are widely used for proportional hazard testing, and summarizes the application condition, advantages and disadvantages of analysis methods for non-proportional hazard survival data. When the non-proportional hazard occurs, we need to choose the suitable method case by case and to be cautious in the interpretation of the results.
Objective When making causal inferences in observational studies, in order to improve the robustness of the results of observational studies, statistical analysis techniques are often used to estimate the impact of unmeasured potential confounding factors. By systematically reviewing the application progress of the E-value, one of the sensitivity analysis methods, the advantages and limitations of using the E-value were discussed, to provide references for the application, reporting and interpretation of the E-value. Methods In the PubMed database, E-value was used as a keyword for title, abstract and key paper citation retrieval, and the literature that used the E-value analysis method for sensitivity analysis during 2016-2021 was screened. Results The E-value was widely used not only in cohort studies (n=215) and case-control studies (n=15), but also in cross-sectional studies (n=28), randomized controlled trials (n=6) and meta-analysis (n=16). The E-value was often combined with other sensitivity analysis methods, such as hierarchical analysis, instrumental variables, and multiple statistical regression models that correct different covariates, to further explore the reliability and robustness of the results. Conclusion When the E-value is used to evaluate the confounding factors in observational studies, the confidence interval and P value can be combined to evaluate the sensitivity of the results more comprehensively.
ObjectiveTo investigate the diagnostic value of lateral chromatography for cryptococcal capsular polysaccharide antigen in cryptococcal infection.MethodsThe data of patients who detected cryptococcal capsular polysaccharide antigen in West China Hospital of Sichuan University in 2018 were collected. The sensitivity, specificity, positive predictive value and negative predictive value of cryptococcal capsular polysaccharide antigen detected by lateral chromatography were analyzed. The samples with positive lateral chromatography and definite clinical diagnosis were compared with the results of ink staining and fungal culture.ResultsA total of 721 cases were detected. The sensitivity, specificity, positive predictive value and negative predictive value of lateral chromatography detection were 100.00%, 99.39%, 93.93%, 100.00%, respectively. The positive rates of ink staining, fungal culture and cryptococcal capsular polysaccharide antigen for cryptococcal infection were 63.46%, 48.00% and 100.00%, respectively. Sixty-two patients were clinically diagnosed, including 45 cases of cryptococcal meningitis (72.58%), 16 cases of cryptococcal pneumonia (25.81%), and 1 case of bone cryptococcal infection (1.61%).ConclusionsLateral chromatography detection for cryptococcal capsular polysaccharide antigen shows well performing sensitivity and specificity in the diagnosis of cryptococcal infection. Considering its rapid and simple pre-operation, cryptococcal capsular polysaccharide antigen detection with lateral chromatography has good application value for early diagosis of cryptococcal infection.