Question: What exactly is a systematic review, and is it substantially different from a review article?

Answer: In the last year, we've talked quite a bit in these columns about evidence-based medicine. One type of article offering evidence and appearing more and more frequently in the literature is the systematic review, which is quite different from the more familiar review article.

Let's start with the review article, also sometimes called a literature or narrative review. In this type of article, authors survey the literature in nonsystematic ways and present their findings as they interpret them. Review articles can be sweeping in their scope or very narrow if the topic is quite specific. Due to the idiosyncratic way in which these reviews are conducted, any conclusions drawn are usually more opinion-based than evidence-based.

A systematic review, on the other hand, provides a very standardized and exhaustive approach to the entire process of literature review. A good systematic review will include detailed information about the procedures used to develop it, such as databases searched, search strategies employed, and limits applied (such as age groups, dates, or language). The criteria used to include or exclude the literature retrieved will be described. And there will be a discussion of how all the relevant data were analyzed and synthesized, what conclusions can be drawn, and the strength of the evidence, if any. 

The transparent documentation of each of these steps enables readers to determine how well bias was eliminated from the process and how robust the conclusions are likely to be. Given how lengthy some of this documentation is, many journals now include some of this material in online addenda.

As you can see, creating a systematic review on a topic is not a quick process, but if it's done well, it will usually produce much more reliable evidence than reviews or reports of single studies. If you're interested in developing a systematic review, consider coauthoring an article with your librarian. She or he has lots of experience in this type of expert searching.  

Question: We are constantly hearing about electronic medical records (EMRs) and electronic health records (EHRs). What's the difference?

Answer: The Pacific Northwest Region of the National Network of Libraries of Medicine offered a recent online class about Health Information Technology, and this was a focus of one of the modules. The non-profit organization Healthcare Information and Management Systems offers a definition of EHR that was cited in the class: 

The Electronic Health Record (EHR) is a longitudinal electronic record of patient health information generated by one or more encounters in any care delivery setting. Included in this patient health information are patient demographics, progress notes, problems, medications, vital signs, past medical history, immunizations, laboratory data, radiology reports, and other medical data.

The key distinction between EMRs and EHRs is that EMRs may simply be a digitized version of a chart. For this reason, EMRs may have no connection to a longitudinal format, without the ability for patients to view their records and without the portability and mobility of the record. What makes an EMR an EHR is the connecting of the EMR to broader networks. If all providers simply digitize their patient records without connecting their systems to patients, pharmacies, labs, and other systems, the potential benefits of systemic EHR can't be realized and can't move beyond an EMR.

Another resource that provides an excellent description of the difference between EMR and EHR comes from the federal Office of the National Coordinator for Health Information Technology (ONC). ONC also notes the “network” focus of an EHR that moves beyond simply collecting and digitizing medical data to include information about other aspects of health as well:

They (EHRs) are built to share information with other health care providers, such as laboratories and specialists, so they contain information from all the clinicians involved in the patient's care. The National Alliance for Health Information Technology stated that EHR data “can be created, managed, and consulted by authorized clinicians and staff across more than one healthcare organization.”

Jim Anderson is a clinical informatics educator for University of Washington Medicine—IT Services and a member of the clinical faculty of the MEDEX Northwest PA program at the University of Washington School of Medicine in Seattle. Susan Klawansky is a medical librarian at Seattle Children's Hospital.