Evidence based medicine in inborn errors of metabolism: is there any and how to find it

Evidence based medicine (EBM) represents an attempt to assist healthcare providers in basing clinical decisions on the best available evidence. That evidence in the treatment realm usually takes the form of clinical trials (CTs), with the randomized controlled clinical trial (CCT or RCT) being the gold standard. Many specialties such as internal medicine have embraced EBM. Medical geneticists who care for patients with inborn errors of metabolism (IEM) have by and large not benefited from the EBM movement. IEM are rare genetic conditions, many of which are treatable. Therefore, the principles of EBM should be applicable to IEM. Notably, Archibald Cochrane, one of the founders of EBM, suffered from porphyria, an IEM. The principles of EBM as applied to IEM are explored herein. The author hypothesized that EBM has not infiltrated the specialty of medical genetics, that few controlled trials for IEM have been published, and that where CTs have been carried out in IEM they can be difficult to find with electronic bibliographic database searches. To test the hypothesis, MEDLINE searches for CTs were carried out for a few representative IEM. The search results support the hypothesis. In this article, the principles of EBM are introduced and its history reviewed as background information to lay the groundwork for further discussion. Next, the dearth of evidence base in IEM, impediments to the application of EBM to IEM, steps to be taken to improve the evidence base for IEM, and finally strategies to make it easier to find CTs for IEM in database searches are all discussed.