Choosing Appropriate Resources for Primary and Secondary Literature 

 

Welcome to the EBM Express course's Choosing Appropriate Resources for Primary and Secondary Literature section. EBM Express is designed to build your understanding of evidence-based practice in short, manageable blocks of content. 

In this module, we will identify resources for finding primary and secondary literature.  

We defined primary and secondary literature in an earlier module. To review, primary literature consists of original materials that are authored by researchers. They describe one research project or study and are usually published in peer-reviewed journals. Primary literature may also include Grey Literature, which is “information produced on all levels of government, academic, business, and industry in electronic and print formats not controlled by commercial publishing.” Some examples of grey literature include conference presentations or abstracts, dissertations or theses, government publications, pre-prints, preliminary reports, and unpublished trial data.  

Secondary literature, on the other hand, is filtered or synthesized information. These interpretations and evaluations are derived from or refer to the original source. Secondary literature includes systematic reviews, meta-analyses, evidence-based practice guidelines, critically appraised topics, and consensus development reports. 

The resources shown here are free to search, and most have some freely accessible materials.  

Cochrane Library contains the Cochrane database of systematic reviews and the Cochrane Central Register of Controlled Trials. Google Scholar searches everything, including organizational websites and books, so it is broader in scope. PubMed has some free articles available through PubMed Central. Trip is a clinical search engine that allows users to find research evidence quickly and easily. The filters on the left make narrowing down results to primary and secondary literature easy. medRxiv is a free online archive and distribution server containing unpublished manuscripts (preprints) in the medical, clinical, and related health sciences. Because these are preprints, they have not been peer-reviewed, so they must be assessed before using them.  

The resources listed here are subscription-based. Embase is a biomedical database similar to PubMed, but it indexes around 3,000 journals that are not included in Medline. It features a wider array of international research and includes numerous conference abstracts. Additionally, it offers extensive coverage of pharmaceuticals. Scopus and Web of Science contain citations from high-impact journals across multiple disciplines, including health sciences, social sciences, engineering, arts & humanities, and more. APA PsycINFO is an abstract and index of psychology and the psychological aspects of related disciplines, such as medicine, nursing, sociology, business, education, etc.  CINAHL is a nursing and allied health database. TripPro is the paid version of Trip. And a Cochrane Library subscription provides more access than the free version.  

Places to search for grey literature include databases, either free or subscription, and search engines or search portals.  

ClinicalTrials.gov provides information about clinical research studies to the public, researchers, and health care professionals. NLM Bookshelf provides free online access to books and documents in life science and healthcare. Sigma Repository is a free, open-access resource provided by the International Honor Society of Nursing. OAlster: Find the pearls includes theses, technical reports, research papers, and image collections. 

Subscription databases include Healthcare Management Information Consortium (HMIC), ProQuest Dissertations & Theses, and PsycEXTRA.  

Several search engines or portals are listed here that you may also explore. 

In this module, we identified many subscription-based and open access options to search for primary, secondary, and grey literature.