In certain situations, which occur with particular frequency in the field of surgery and its related disciplines (where what predominates are observational-type studies), the management of randomized controlled clinical trials (RCT) is very difficult and as such, conducting a systematic review (SR) based on RCT and realice a meta-analysis is even more difficult. Therefore, we have generated a methodology for implementing a SR with different types of designs (including observational studies) as an alternative in order to clarify the uncertainty in the field of therapy when there are few RCT and the evidence relies so heavily on descriptive and observational studies. The aim of this study, was to set out a methodology that leads to a SR with various types of... |