In order to plot out our research course for the future, we have to know where we’ve already been. What has already been studied? What questions have already been answered? What remains unknown? We answer these questions by completing a review of the medical literature.
Sounds easy enough, doesn’t it? We just need to do a quick search on PubMed (which catalogs all the manuscripts published in most academic journals). Then, we just read them all and VOILA! Literature review complete!
Unfortunately, this is not the way it works.
The first step in performing a quality literature search is the search itself. We often have to use multiple different search terms and weed through the results to find the articles that are relevant to our research questions. This is often easier said than done. For example, let’s say we want to look for all the articles ever published about 18q-. We would have to use multiple search terms, including “18q-“, “deletion 18q”, “de Grouchy syndrome”, and several others in order to capture all the articles that have been written about this condition.
Once we’ve created the list of articles we wish to review, we actually have to track down those articles! This is pretty straightforward, but it can be time-consuming! Some articles are available online, but many (especially the ones published several years ago) have to be manually located and copied. Or, if the library does not subscribe to a particular journal, the article must be ordered from another institution.
Usually, the stack of articles is at least several inches thick, if not more. Now the REAL work can begin! We read each article carefully and thoroughly, looking for information that is relevant to our research questions. We’re looking not only for information about the clinical features of the condition, but also information about the molecular nature of the genetic change. It is important to read all manuscripts with a critical eye and ask the question, “Does this relate to the questions we’re asking? Did the authors use appropriate methods to get their data? What are the conclusions of this paper? What impact does this paper have for the direction of our research?”
Of course, the literature review is not something that is every truly completed. Hundreds of articles are published every month, so we must repeat our original searches every so often to make sure that we catch any new information that is out there.
Once we have a good idea of what is already out there, we can move on to the next step in the research process: the Clinical Assessments.