I just wanted to give a brief nod to a great, little book I read recently, The Pocket Guide to Critical Appraisal by Iain Crombie. In a grand total of about 60 pages, the book gives a concise explanation of how to read and evaluate the quality of a published scientific paper.
As I’ve pointed out before, just because an idea or a study is published in a journal doesn’t mean the idea is correct of the study meaningful. The problem of Tooth Fairy Science, the creation of journals just for the purpose of promoting specific products or medical methods, the influence of funding bias, and many other factors external to a scientific paper influence whether the results and conclusions offered are reliable. But there are also many factors to consider within the paper itself when trying to decide if the information presented is reliable or useful, and it is this internal assessment the Pocket Guide to Critical Appraisal is intended to assist.
After a brief introduction to the general issues involved in assessing scientific studies of various kinds, the book presents step-by-step checklists for the major types of study, including surveys, cohort studies, case-control studies, and clinical trials.
Despite the impression created by the media, and often proponents of dubious medical interventions, that anything published in a journal can be trusted to mean what the authors say it means, the reality is that all scientific evidence should be carefully an cautiously scrutinized before we rely on it to inform how we treat our patients, our pets, or ourselves. Otherwise, there is a great risk that we will waste resources on useless or even harmful treatments or avoid truly beneficial ones on the basis of poor evidence. This book makes such scrutiny relatively straightforward even for the non-specialist.