Systematic Review

At a conference I attended this weekend, one of the topics was the level of understanding needed to assess a study. The question went something like this: If a clinician doesn’t understand how research is conducted or if the statistical tests used are valid, can the clinician really assess the validity and usefulness to practice of any study?

It’s a good question. I’ve seen midwives and doulas cling to one piece of research over another not because the results were more robust, but because the authors conclusions were in line with what the midwife wanted to believe. But the results are only as good as the quality of the research methods.  I just read an article last night that concluded induction of labor at 41 weeks for postdates and expectant management result in the same rate of cesarean – but upon critical review of the article I noticed the subjects were divided into groups based on the preferred practice of the physician attending that woman. This tells me the paper is NOT about the overall differences of the two protocols because too much other pieces of practice style is built into the dividing of the two groups.

In a class I am working with a group of nurses were concerned they shouldn’t pursue their topic for an evidence based practice project because there was already a systematic review, and doesn’t that mean the question is already answered.  Actually, no.  A systematic review is a very specific overview of what information is available.  The results are going to be based on the inclusion and exclusion criteria – which means there are many pieces of research that may pertain to the topic that are not included in the review.  The review may add some validity to a line of thought about the question, but cannot be the final answer.  And a review cannot “keep up” with new research, it is a glimpse of the literature at a specific point in time. The publishing of a single systematic review (or writing of a guideline or protocol) should never prevent clinicians from regularly reviewing and revising practice – without reviewing practice regularly a clinician would miss new information that may change the understanding and types of care given.

With all these questions in mind, I want to share this learning module:

Cochrane Collaboration

It can help you understand how a systematic review is performed, so you can be a better consumer of research.