ObjectiveTo introduce Bayesian meta-analysis of dichotomous data using PROC MCMC in SAS software.MethodsA previous published systematic review was used as an example, Bayesian meta-analysis of dichotomous data was implemented by PROC MCMC in SAS software, and programming code was provided.ResultsThe log-transformed value of odds ratio (OR) was used as the efficacy. The results of the Bayesian meta-analysis were very similar to those obtained by the frequency method.ConclusionsBased on the powerful programming capabilities of SAS, PROC MCMC can easily implement Bayesian meta-analysis of dichotomous data. With the rapid development of Bayesian statistical theory, Bayesian meta-analysis will play an important role in the field of meta-analysis.
The meta-analysis of rare binary data is a difficulty in the field of medical research, and its methodology remains immature. The traditional meta-analysis technique is based on the normal-normal model of fixed effects analysis or random-effects analysis, however there are methodological problems in this method. Stijnen proposed an exact within-study likelihood models (EWLM) meta-analysis technique based on the generalized linear mixed model (GLMM), including the binomial-normal model (BN) and Hypergeometric-normal model (HNM), which can be used to achieve random effects meta-analysis of rare binary data. This paper introduces the model in detail and its implementation in SAS software with examples to provide relevant SAS code.
ObjectiveTo introduce a meta-analysis of linear or nonlinear multilevel models using SAS MIXED and SAS NLMIXED.MethodsA systematic review performed to evaluate the risk of local recurrence in patients with cervical cancer treated with radical chemoradiotherapy and adjuvant surgery published by Shim et al. was selected as an illustration. An SAS software was used to implement meta-analysis based on linear or nonlinear multi-level models, and programming codes were provided.ResultsIn the absence of covariates, the OR combined effect values of PROC MIXED based on the bivariate random effects model and PROC NLMIXED of the nonlinear mixed effects model were 0.63 (95%CI 0.46 to 0.87, P=0.005 7) and 0.60 (95%CI 0.39 to 0.81, P=0.000 3), respectively. In the case of covariates, the bivariate random effects model and the nonlinear mixed effects model provided an effect value of OR=0.65 (95%CI 0.47 to 0.91, P=0.011) and 0.59 (95%CI 0.38 to 0.80, P=0.000 3). Covariate OR effect values were 2.70 (95%CI 0.16 to 45.23, P>0.05) and 1.86 (95%CI −0.07 to 3.79, P=0.06).ConclusionsThe meta-analysis results of the SAS NLMIXED nonlinear mixed-effects model are similar to those of the SAS MIXED linear mixed-effects model. PROC NLMIXED has powerful programming capability and nonlinear mixed-effects model has flexible modeling capabilities for sparse data. Therefore, PROC NLMIXED will play an increasingly important role in meta-analysis.
Longitudinal data had intrinsic correlation problems at different time points, and traditional meta-analysis techniques cannot resolve this problem. Regression coefficients based on multi-level models can fully consider the correlations of longitudinal data at various time points. This paper uses SAS software to perform multi-level regression coefficient model meta-analysis and provides programming code which is simple and easy to operate.
Despite the rapid development of meta-analysis technology, there were currently no consolidation technology for longitudinal data. The meta-analysis model based on the generalized linear mixed-effects model can fully encapsulate the correlation between various time points and accurately estimate the final combined effect, which is an ideal model for longitudinal-data meta-analysis. Through example data, this paper used SAS software to realize longitudinal-data meta-analysis and provided programming codes.
Objective To evaluate the radical chemoradiotherapy plus surgery for locally advanced cervical patients. Methods 102 cases of patients with locally advanced cervical cancer were randomly divided into a trial group and a control group. In the control group, patients received radical chemoradiotherapy only, with chemotherapy consisted of cisplatin 35-40 mg/m2, one times a week. In the trial group, patients received both treatment in the control group and extensive hysterectomy and pelvic lymph node dissection. Results Fifty-two patients were randomly enrolled into the trial group and 50 patients into the control group. The microscopic residual tumor (MRT) rate was 5.8% (3/52) and non-microscopic residual tumor (NMRT) rate was 82.7% (43/52) in the trial group. Progression-free survival time was 3-40 months with a median survival time of 23 months, and the 3-year progression-free survival rate was 73.1% in the trial group, and progression-free survival time was 5–41 months with a median survival time of 22 months, and the 3-year progression-free survival rate was 64.8% in the control group; while the difference was not statistically significant (χ2=0.092,P=0.761). Overall survival time was 6–40 months with median overall survival time of 23 months, and the 3-year overall survival rate was 82.7% in the trial group, and overall survival time was 5-41 months with a median survival time of 22.5 months, and the 3-year overall survival rate was 81.8%; while the difference was not statistically significant (χ2=0.338,P=0.561). Conclusion Concomitant chemoradiation followed by radical surgery could not significantly improve progression-free survival and overall survival in patients with locally advanced cervical cancer. The treatment regimen should be applied with caution and selectivity.
ObjectivesTo compare the efficacy and safety of weekly nedaplatin compared with weekly cisplatin as postoperative concurrent chemoradiotherapy scheme for cervical cancer patients.MethodsThis trial was performed in the Department of Radiation Oncology in the Second Affiliated Hospital of Fujian Medical University from June 2016 to January 2017. A total of 200 patients with stage ⅠB1-ⅡB cervical cancer were randomly assigned to the nedaplatin group and the cisplatin group after signing informed content. The dose of nedaplatin or cisplatin ranged 35 to 40 mg/m2, once a week for 5 weeks. Intensity-modulated radiation therapy or three-dimensional conformal radiation therapy were used for patients. The progression-free survival, overall survival and adverse reactions were compared between two groups. Statistical analysis was performed by SPSS 24.0 software.ResultsA total of 105 patients were enrolled in the nedaplatin group, and 95 patients were in cisplatin group. The three-year progression-free survival rate was 80.5% vs. 79.5% in the nedaplatin group and the cisplatin group, respectively; and no statistical significant difference was found (χ2=0.198, P=0.656) between two groups. The 3-year overall survival rates were 72.5% and 69.9% for the nedaplatin group and the cisplatin group, respectively, and there was no significant difference between the two groups (χ2=0.261, P=0.609). The incidence of grade 3/4 nausea and vomiting in the nedaplatin group was 6.67%, which was significantly lower than that of 15.79% in the cisplatin group, and statistical significant difference was found (χ2=2.555, P=0.011); however, the incidence of grade 3/4 thrombocytopenia in the nedaplatin group was 9.52%, which was significantly higher than that in the cisplatin group (3.15%); and the difference was statistically significant (χ2=1.985, P=0.047). There was no difference in the incidence of adverse reactions such as anemia, neutropenia, and radiological proctitis in both groups.ConclusionsNedaplatin-based concurrent chemoradiotherapy has similar efficacy compared to cisplatin-based concurrent chemoradiotherapy, and it could significantly reduce the digestive tract reaction, which can be used as an alternative to cisplatin.
ObjectivesTo explore the efficacy of simultaneous chemoradiotherapy combined with surgery for locally advanced cervical patients and perform multivariable analysis.MethodsA total of 130 cases of patients with locally advanced cervical cancer who were admitted to the Second Affiliated Hospital of Fujian Medical University from June 2012 to December 2016 were randomly divided into case group and control group. The patients in the control group were treated with platinum-based radical concurrent chemoradiation. In the case group, patients received both treatment in the control group with the addition of extensive hysterectomy and pelvic lymph node dissection. The short-term efficacy and survival outcomes of the two groups were compared.ResultsThe present study was the final report of this randomized controlled trial. 68 patients were randomly enrolled into the case group and 50 patients into control group. The non-microscopic residual tumor (non-MRT) rates were 83.8% (57/68) and microscopic residual tumor (MRT) rates were 2.9% (2/68) in the experimental group. There was no significant difference between two groups (χ2=0.008, P=0.928) in 3-year progression-free survival rate (65.6%vs. 59.6%) and 4-year progression-free survival rate (52.5% vs. 56.3%). And there was no significant difference between two groups (χ2=0.361, P=0.548) in 3-year overall survival rate (80.3%vs. 74.6%) and 4-year overall survival rate (77.6% vs. 64.9%). Multivariable analysis showed that only tumor size and parametrial invasion were significant prognostic factors of PFS (P<0.05). And only parametrial invasion was a potential prognostic indicator affecting OS (P=0.078).ConclusionParametrial invasion is an important prognostic factor. Radical concurrent chemoradiotherapy combined with surgical treatment of locally advanced cervical cancer has not significantly improved progression-free survival and overall survival. The treatment regimen should be applied with caution and selectivity.