What Should Be the Ideal Control Group in Clinical Trials Investigating the Role of Varicocele and Its Treatment on Fertility Outcomes?

  • Renata Cristina de Carvalho
  • Renato Fraietta


Varicocele is a condition capable of affecting the male fertility potential. The decision of treatment depends on how the disease is harming the individual, but the real effectiveness of an intervention can only be evaluated by studies named clinical trials. A clinical trial evaluates the intervention effectiveness over a specific condition and for that requires a comparative group called control group. There are three different approaches on varicocele treatment studies, and all of them require a control group. When studying the treatment effects over treated and untreated groups, the control group is the one which has not received the treatment. When comparing two different therapies, the control group is the one receiving the gold standard treatment. Studies analyzing the same treatment offered in different points of time consider control group the one which receive treatment on the commonly well-established point in time. Therefore, control group should be the one that best fits for the purpose of a certain study.


Varicocele Fertility Treatment Clinical trial Control group 


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© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Renata Cristina de Carvalho
    • 1
  • Renato Fraietta
    • 1
  1. 1.Department of Surgery, Division of UrologySao Paulo Federal UniversitySao PauloBrazil

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