To the editor:
Systemic review is a process by which the results of many studies are integrated to form a coherent and probable conclusion. Systemic review is most often used when there are conflicting or diverging results from studies and papers. When reading an article on a controversial public health topic, first determine if the author is quoting a single study, or multiple studies.
A systemic review of a topic requires extensive research with the goal of reducing bias. According to the National Institutes of Health, bias is reduced by “identifying, appraising, and synthesizing all relevant studies on a particular topic.” When evaluating the efficacy of a systemic review, the expertise of the researcher or researchers should also be considered.
For example, a systemic review of coronary heart disease studies conducted by a team of thoracic surgeons, should result in high confidence in the review’s conclusions. If, however, the systemic review was conducted by a team of Historians, confidence should be lower. However, if a systemic review of the publications on the causes of WWI is conducted by the same groups, the conclusions from the team of historians are probably more reliable.
When you read about a controversial health or scientific topic in your local newspaper or popular magazine, please consider whether the author considered all relevant studies and data and what is their expertise? Let us all take a lesson from the disastrous anti-vax movement, and not fall into the same trap with other health related topics.