Systematic reviews and librarians.

ABSTRACT

Systematic reviews are review articles that are completed using predefined methods to minimize bias inherent to observational studies. Systematic reviews are important to librarians because they integrate evidence across studies or data resources to provide knowledge that is useful to good decision making in our profession. In addition, as more systematic reviews are being published in many disciplines, librarians are being asked to assist with the production of them--comprehensive searching is vital to the strength of the reviews. This article describes the process of producing systematic reviews and also describes their use. Librarians can acquire the skills necessary to use and produce high-quality systematic reviews.

INTRODUCTION

This article is designed to introduce librarians, both practitioners and researchers, to systematic reviews. I plan to set the context of this article by describing a scenario, define what a systematic review is in relation to all review articles, briefly discuss the history of systematic reviews, and list why they are important to librarians and why they are done. I will also describe the research strengths and quality indicators, show the steps in the production of a systematic review, discuss how one can find them across databases, and resolve the scenario. I include examples throughout the article from the disciplines of library and information science (LIS) as well as health care, the area of librarianship in which I have spent the past twenty years. The examples in this article are ones that I chose to show a specific aspect of systematic review production or use and represent a range of quality and content.

SCENARIO

You have just been promoted to be the head of one of the smaller inner-city branches of your local public library. One of the reasons you got the job is that you stressed the need for evidence from sound research to back up your library's services and collections. Your branch has a long and strong tradition of malay programs and is especially proud of their bibliotherapy programs run in conjunction with the local Department of Public Health. Your library director has just called and asked you to provide evidence concerning the effectiveness of the bibliotherapy programs. You sit down at your terminal and quickly find 252 articles in the National Library of Medicine's (NLM) PUBMED database. You sigh and wish that someone else besides you could "pull" all of these papers together and come up with a sound, evidence-based bottom line for bibliotherapy.

While you are thinking, the phone rings again and it is the director of the Department of Public Health. The city has just realized that their teen pregnancy rate is well above national and state levels and has started to push the Public Health people to "do something." The director, a long-time supporter of your services, asks if you could spare one of your librarians to help them search for and collect literature on prevention of teen pregnancy. The Health Department needs to write a report summarizing the evidence on the effectiveness of various approaches to preventing teen pregnancy and plan for new programs. Again you are faced with compiling the information on a certain topic or area and having it ready for others to apply--in other words, a systematic review of the literature.

WHAT IS A SYSTEMATIC REVIEW?

The research world recognizes two sorts of review articles, both of which are important. Narrative reviews are opinion pieces done by an expert in the field. They are often broad based, written by a single author, and lack formal summaries of whole bodies of knowledge. Narrative reviews provide valuable coverage of an area of knowledge or an introduction to a topic, similar to what would be found in a textbook chapter. Two useful examples of narrative reviews in L1S include bibliotherapy and bullying (Gregory & Vessey, 2004) and public libraries and ethnic minority communities in the UK (Elliott, 1999). Both were written by experts who summarized the content area of their respective topics. Students and those interested in a general summary of a topic value these expert (narrative) reviews.

Systematic reviews, on the other hand, are often much more narrowly focused and are written by a team of researchers who represent a range of skills and interest in the topic. Cook, Mulrow, and Haynes (1997) define them as reviews that assemble, critically appraise or evaluate, and synthesize the results of primary studies in an integrative approach. They continue by listing the features of a well-done systematic review:

1. It defines the question to be addressed precisely and explicitly

2. It includes a replicable search strategy (for example, databases, terms, years, language restrictions, and other limits)

3. It uses pre-set inclusion and exclusion criteria to select articles or data sources that will be summarized in the review

To illustrate the features of a systematic review, it is worth looking at a study by Weightman and Williamson (2005). These authors wanted to examine the research on the value and impact of information about patient care provided by health sciences librarians. Their goal was "to review studies looking at the value and impact of library services on health outcomes for patients and time saved by health professionals" (p. 5).

They searched six databases (Education Resources Information Center [ERIC], PUBMED, Library and Information Science Abstracts [LISA], PREMDELINE, EMBASE[c], and Cochrane Database of Systematic Reviews[c]) using twenty terms in various "and" and "or" combinations. They also searched Google, did a hand search of two journals, and checked all bibliographies of the articles they retrieved. In addition, they contacted authors, used personal reprint collections, consulted peers, and submitted emails to several discussion groups and listservs. Their inclusion and exclusion criteria for individual studies spanned…