Critical appraisal of scientific literature is a necessary skill in my line of work. After selecting an article, you must be able to sit with the article and critically appraise it. The media especially loves to create and over exaggerate health claims made in health literature and in many cases, misinterpreting the evidence positively but also in many cases negatively. This can cause detrimental problems for those people searching for a positive health or lifestyle choice.
Although when an influential Cochrane Library publishes a new study that concludes that there is little or no effect of Omega 3 supplements on the risk of experiencing heart disease, stroke or death. I instantly questioned if the produced findings had limited validity? So I wasn’t surprised when a recent article was emailed to myself from a work colleague, to confirm my concerns. Experts are saying that the trial criteria applied by Cochrane researchers downplayed the benefits of fish oils observed in the study.
Critical appraisal of a journal article is a literary and scientific systematic dissection in an attempt to assign merit to the conclusions of an article. Ideally, an article will be able to undergo scrutiny and retain its findings as valid.
The specific questions used to assess validity change slightly with different study designs and article types. Simply put certain questions are asked such as:
Is the Journal peered reviewed?
Do the authors present a hypothesis?
Do the research methods limit the influence of confounding variables?
Harry Rice, vice president of scientific and regulatory affairs for the Global Organisation for EPA and DHA Omega-3s (GOED), has challenged the findings stating “While the authors should be applauded for the breadth of their review, their overall interpretation of the data demonstrated a lack of appreciation for and understanding of the decades of research demonstrating the heart health benefits of omega-3s. Such research includes not just meta analyses, but RCTs, observational studies as well as animal an in vitro studies. It’s about the totality of the scientific evidence.”
With other researchers questioning the selection criteria used? As most of the trials including people with pre-existing cardiovascular disease (CVD), which could further limit when presenting the evidence to the PREVENTION of heart attacks in the general population
You could also question if Cochrane attempted to contextualise non-significant data in an attempt to portray significance? (E.g. talking about findings which had a trend towards significance as if they were significant).
For me questioning what you believe could benefit is an important role of human nature that we should not ignore as individuals. A point proven scientifically by looking closer at the evidence presented.
So I will keep eating oily fish and taking my Omega 3 supplement.
Warning: Fish Oil should not be supplemented if you have been prescribed any form of blood thinners or before an operation. Its best to discuss any form of supplementation with a health care professional.
Thank you for reading.
