There are reviews and reviews. In my field, I often come on "reviews" talking about some chosen publications/investigations. They are not worth mentioning (maybe you can find one or two leads in the references). Systematic reviews are very useful. Again, you have to analyse the review criteria similar to analysing the criteria in a single investigation. With luck, you find one at Chochrane, or some HTA.
And of course, take care about duplicate data. I have seen trials that have published interim reports on a yearly basis, "review" articles comparing to one or two other trials, and analyses of aspects not originally included in the trial. You have to consolidate that, drop all interim reports but the last (or final) report, explain what data you take from the "other aspects articles".
You find industrious scientists/practitioners that publish a case series of 40 patients from 2007 to 2010, and another one of 100 patients from 2008 to 2015, and a third one on 150 patients from 2012 to 2018. Maybe including several/different generations of the device, containing duplicate patients. They usually forget to include data to exactly identify the overlap.