Reviewer's comment concerning 'Does sagittal position of the CTDR-related centre of rotation influence functional outcome? Prospective 2-year follow-up analysis' (doi:10.1007/s00586-014-3223-0 by P. Suchomel et al.)

摘要

I was asked to write a reviewer's comment on the above-mentioned article by P. Suchomel et al. because I expressed a skeptical attitude towards it. I am happy to elaborate why. The study presented here is a typical post-market observational study of a device, in this instance of a specific CTDR with two different designs. These studies are usually triggered by the respective companies and have their justification. They serve to detect major safety issues once the product is licensed and available for everybody. This is what they are designed for. No less, no more. They are not designed for valid intergroup comparisons. Thus, the conclusions of this communication are not borne by hard facts, but are a mere leap of faith, which starts at the outset and remains a self-fulfilling prophecy throughout.