Wednesday, October 16, 2013

The art of medical literature review -- Lessons from a distant era

It just took me 20 years to write a two page paper.

The specific subject is not important to this posting (a trick to learn and recall a particular area of neuroanatomy). However, the epic adventure of producing this paper spanned a transformational period in the history of knowledge and learning. The roots of the paper were formed in the pre-Internet era; the fruit were harvested in the current environment of instant hyper-connectivity. The benefits of widespread computing and networking are obvious to all. However, reflecting on this experience it occurs to me that there were some benefits to the old ways; there are some lessons the “digital natives” can learn from the ancient “digital immigrants”.

First, the story. In 1990, I was a resident preparing a grand rounds presentation. The topic (again, not important to the story) was neuralgic amyotrophy, or Parsonage-Turner Syndrome. Preparation required an extensive review of the available medical literature. Today, this task would be performed at my desk, and the pertinent papers downloaded instantly, in less time than it took to type this posting. Here is how it worked in 1990. To some, this will seem like monks hand-copying books:

To begin, you identified key words that were used to catalog references in the Index Medicus. The Index Medicus was founded in 1879, and was in continuous print publication until 2004. Ultimately, it evolved into the National Library of Medicine (NLM) and all references may now be accessed electronically via PubMed. (for a brief history of the Index Medicus, click here)


In 1990, the Index Medicus was published as a single volume, bound annually, with monthly updates for the current year. To perform a literature review, you had to physically pull each bound copy, look up your key words, intuit from the title of the article if was pertinent to your topic and write down the reference. You then repeated that task for the previous year…and the year before…and the year before…until you were satisfied you had searched far enough back into the literature.

Next, it was time to find the actual articles. Depending on your project, you might need at least a dozen references; another project may require more than one hundred). With your references written on a legal pad, you entered the library stacks…multiple floors of bookshelves, usually dimly lit, with the unmistakable odor of old books. You had to pull each bound journal, locate the article, and scan it to see if it contained information of interest to your quest. If it passed muster, you would add it to a wheeled cart and proceed to the location of the next journal. Since the stacks were generally multiple floors, and elevator was involved. At times, the bound copy of a particularly important article was missing, or torn out of the journal by some academic miscreant. In these cases, you had to meet with the librarian to request that a copy be mailed (that is, using a stamp and a postman) from another library.




With your cart in tow, you then proceeded to the copy room to make copies of your collected articles. This sometimes involved standing in line, as others were also copying dozens of articles. Then, simple as that, your initial literature review was complete. You were finally ready to read, synthesize and write.

The entire process took at least several hours -- often days, or even weeks. The ability to search the entire medical literature, nearly instantaneously, from virtually any device, is clearly a quantum leap from the old method. It is a leap that we all now take for granted. But was there anything valuable lost in the transition?

Back to my grand rounds. As I was in the “stack wandering” phase of my project, I picked up a journal containing one of my many references. As I flipped to the appropriate page, my eye was caught by a brief paper in the same journal. It was on an entirely unrelated topic – brainstem anatomy. I read it and learned a simple anatomical trick. I started using the trick clinically, found it useful over several years, altered it a bit and started teaching it to others. Eventually, I decided to try and publish it. To this day, I have never been able to locate the article I stumbled across serendipitously. I did find others, and consolidated their concepts with my memory from the mystery paper (http://www.ncbi.nlm.nih.gov/pubmed/24713180).

So what lessons can be learned from the old ways? I think there are several:

Planning. The review process outlined above was incredibly labor intensive, and could not be easily delegated. The potential for lost time forced people to plan their literature review in advance. A primary role of a medical librarian was to assist in the development of a search which was systematic and thorough, but also time efficient.

In the current world of instantaneous searches, it is easy to use the first couple of key words that come to mind, cross reference them and generate what seems to be an adequate number of references.

Modern searchers should still invest in time to plan an important search in advance. Although time efficiency is no longer be an issue, it is still necessary to be systematic and thorough.

Quality trumps quantity. The modern search generates a tremendous volume of references. The old search methods tended to produce a more thoughtfully assembled list. The old methods felt more like being a collector of stamps or porcelain figurines – the collector, over a long period of time, searches for and acquires a particular piece that helps to augment the collection. The new methods feel more like a money whirlwind machine on a game show (Click here if you do not know what this is). The searcher grabs as many bills as possible, as quickly as possible, until time runs out.

Modern searchers could benefit from treating their efforts more like the assembly of a treasured collection.

Create quiet space. The old search process was incredibly inefficient. There was a great deal of inherent wasted time, rifling through the Index Medicus and combing through the stacks. However, it was also a very peaceful experience. The information came slowly, in bits and pieces. There was time for your mind to wander, and to ruminate on something you just read. If ideas tend to come to you in the shower, you would likely have the same experience in the stacks. Modern searchers would be well served by actively working to create quiet, reflective time, free of all distractions.

Faster is not always better.