Alternative statistical modeling for radical prostatectomy data.

Several statistical models have been proposed in recent years, among them is the semiparametric regression. In medicine, there are several situations in which it is impracticable to consider a linear regression for statistical modeling, especially when the data contain explanatory variables that present a nonlinear relationship with the response variable. Another common situation is when the response variable does not have a unimodal shape, and it is not possible to adopt distributions belonging to the symmetric or asymmetric classes. In this context, a semiparametric heteroskedastic regression is proposed based on an extension of the normal distribution. Then, we show the usefulness of this model to analyze the cost of prostate cancer surgery. The predictor variables refer to two groups of patients such that one group receives a multimodal local anesthetic solution (Preemptive Target Anesthetic Solution) and the second group is treated with neuraxial blockade (spinal anesthesia/traditional standard). The other relevant predictor variables are also evaluated, thus allowing for the in-depth interpretation of the predictor variables with a nonlinear effect on the dependent variable cost. The penalized maximum likelihood method is adopted to estimate the model parameters. The new regression is a useful statistical tool for analyzing medical data.

Homemade laparoscopic simulator.

PURPOSE: To describe a guide for the construction of a laparoscopic training simulator. METHODS: Step-by-step description of an inexpensive and easy to assemble homemade laparoscopic training box, capable of simulating the laparoscopic environment in its peculiarities to enable technical skills training. RESULTS: The total cost of the materials for the construction of the simulator was US$ 75.00 (about R$ 250.00 "reais") and it can be reduced to US$ 60.00 if the builder judges that there is no need for internal lighting. The use of real trocars imposes the same challenges as real surgeries regarding positioning, visibility and limitation of movements. CONCLUSION: The proposed economical and efficient alternative can contribute to the teaching and practice of laparoscopic surgical technique worldwide, benefiting surgeons and patients.

Homemade laparoscopic simulator

Abstract Purpose: To describe a guide for the construction of a laparoscopic training simulator. Methods: Step-by-step description of an inexpensive and easy to assemble homemade laparoscopic training box, capable of simulating the laparoscopic environment in its peculiarities to enable technical skills training. Results: The total cost of the materials for the construction of the simulator was US$ 75.00 (about R$ 250.00 "reais") and it can be reduced to US$ 60.00 if the builder judges that there is no need for internal lighting. The use of real trocars imposes the same challenges as real surgeries regarding positioning, visibility and limitation of movements. Conclusion: The proposed economical and efficient alternative can contribute to the teaching and practice of laparoscopic surgical technique worldwide, benefiting surgeons and patients.