Do research articles that are flawed get published?
For about 10 or 11 years, I have been on the editorial board of the Journal of Orthopedic and Sports Physical Therapy. I have reviewed for multiple other journals as well.
The sad truth is, yes. You may ask, how can that happen? Don't these journals have quality controls? Aren't there reviewers with a string of initials behind their name who are paid to review these things and make sure no fatally flawed evidence shows up in our journals?
You have to realize that this is a human effort. As a reviewer, you are actually not paid. We do this as a labor of love. Most reviewers for journals are academicians and some are clinicians. Essentially, all are asked to review on a pro bono basis. We are reviewing these manuscripts in the evenings and on weekends. It is an imperfect process. I think that all of the people engaged are full of integrity in doing their best. But, there are definitely articles that slip through the net and get published with serious validity threats - some serious flaws. We all have to have the skills to perform critical appraisal ourselves.