Searching for Evidence





The changing shape of information and how it is retrieved and evaluated has profound effects at every level of the research process. The emphasis on evidence-based decision-making in healthcare, coupled with the exponential increase in the volume of scientific literature, have resulted in a more complicated research environment. Although the core concepts of research have remained relatively consistent, new tools and technologies continue to evolve and multiply. This chapter discusses the search for evidence as a systematic process consisting of four distinct phases including preparation and planning, searching the literature, going beyond the literature, and pulling it all together.

One of the most dramatic changes over the past 10 years affecting all types of information gathering has been the sheer increase of available information. In 2014, Larosa estimated that PubMed, a health sciences literature database, adds approximately 500,000 new records every year and its collection doubles every 13 years (Larosa, 2014). More recent statistics show that the pace of new records is increasing, with an average 1.2 million additional new records every year since 2014 (National Library of Medicine, 2019). While the explosion of information continues, the skills to navigate through denser and more crowded information landscapes seldom keep pace (Christenbery et al., 2016). Advanced practice registered nurses (APRNs) may be overwhelmed with available evidence and find it difficult to maintain searching skills and to keep up-to-date in their fields. Barriers such as time, lack of resources, or appropriate skill sets remain an issue in translating research into clinical practice (Fencl & Matthews, 2017). The heightened focus in recent years on improving clinical outcomes through support of scientific knowledge has resulted in a greater emphasis on the integration of evidence-based practice (EBP) at all levels of healthcare (Fencl & Matthews, 2017; Taylor et al., 2016). As nursing students and healthcare professionals learn to incorporate EBPs into their clinical workflow, they must learn to identify evidence-based information resources and construct related information-seeking strategies. Effective EBPs will be increasingly important in saving clinician’s time and energy and, ultimately, in achieving improved clinical outcomes (Polit & Beck, 2020).


Since 2001 when the Institute of Medicine (IOM, now known as the National Academy of Medicine) called for all healthcare professionals to incorporate the concept of EBP into practice, the need to search for evidence has become paramount (Cypress, 2019). The concept of literature searching encompasses far more than merely entering words into a search box. The process 16includes formulating search statements, selecting appropriate search terminology, and locating databases and strategies; a literature review, in actuality, is a robust project waiting to be organized. Contemplating and identifying its various parts before approaching a database is time well spent. Not only will this prep work benefit the searcher in time saved, it will instill order in what may seem to be a frustrating string of chaotic activities. The preliminary literature review preparation phase will be discussed in this section.

To use an analogy, anyone who has been challenged by the prospect of cooking using a new recipe can find the task either daunting or unnerving. In order to make sense of the process, we find ourselves first reading the entire recipe from beginning to end before assembling the ingredients for the dish. Once we understand what the finished product should be, we gather appropriate ingredients and the necessary utensils. As the cook gains more confidence in their skills, there is more certainty in the procedure and a pattern begins to develop. As patterns develop, variations are incorporated with ease and confidence increases over time.

Research is much the same. If searching a database is a rare occurrence, it will seem to be a slow, laborious, and unwelcomed process. As the practice of research is integrated into clinical cultures and professional workflows, the familiarity of the process will become second nature as well.

Ask Yourself Some Questions

Before diving head-first into database searching, it is important to ask a few questions to guide subsequent actions (Exhibit 2.1). Pre-search preparation will tease out existing strengths and weaknesses, define the skills needed, and pinpoint knowledge gaps. Questioning the purpose of the literature review will determine the intent and the appropriate intensity, depth, and scope of the search(es).

An inclusive search for all relevant literature, such as demanded by systematic reviews and meta-analyses, requires more time and involves more databases than a selective review of limited scope. Which resources are best for the research question? It is advisable to identify the best information resources for the topic before constructing search strategies. Good preparation prevents 17distracting detours and lost time, resolves confusion, and serves to sequence the order in which databases are searched. In Phase I, exploratory searches are important for discovery and to determine the viability of the research topic.

Define the Search Goal

Defining the scope of the planned research is an important element in moving forward. Assessing the intended outcome of the search will provide a clarity of purpose and direction. Is the impending literature review a class assignment with specific guidelines, requirements, and deadlines? Is it generated by unanswered healthcare questions that need immediate attention? Is it part of a team project leading to the creation of evidence-based guidelines in the clinical setting? Answers to these questions may drive the momentum of the literature review down slightly different search paths. Decisions made at this juncture will also impact the choice of databases and resources consulted. One size does not fit all. A small-sized research goal does not warrant an extensive research approach. Each literature review is a sum of its smaller parts.

Gather Background Information

One important preliminary step is to understand how the research topic fits into its related field of knowledge. The APRN must attain some degree of comfort with the nomenclature and the topic-at-large before moving into serious search phases. A good background builds an information foundation that will support increased awareness of vocabulary (important when searching) and related issues. Background information can be found in many places, including textbooks, trusted websites, reference resources, clinical summary databases (CSDs; discussed later in this chapter), and review articles. If the topic is interdisciplinary, as many nursing topics are, the information destinations will be broader in scope, more numerous, and often less familiar. Reaching across disciplines can be a stretch, especially for the less experienced searcher. During the background gathering, it is advisable to clearly list and expand related terminology to aid in search strategy construction later.

Construct a Searchable Question

First, formulating a searchable or answerable question is a technique that focuses on the most basic elements of the research topic. A poorly constructed research question makes searching frustrating by wasting time or returning too many or off target results. Spending time to create a “searchable question” will allow the researcher to focus search terms, database limiters, and find appropriate and useful literature (Bramer et al., 2018).

By focusing on only the core elements of a complex healthcare scenario, the central question gains clarity and more precise definition. Precision and focus are also enhanced by the use of the PICO method developed by proponents of EBP. The PICO mnemonic (P = patient, population, problem; I = intervention; C = comparison; O = outcome) provides a useful instrument for peeling away the outer layers of the research question and directs the focus to only the most essential components. PICO is widely used for quantitative research questions.

Alternatively, the PEO mnemonic (P = populations and their problems; E = exposure; O = outcomes or themes) provides a useful instrument for peeling away the outer layers of qualitative research questions. Either structure can be used to create a clinical question; however, not every clinical question will fit neatly into both frameworks, but the approach of deconstructing the parts to their meaningful essence will clarify the purpose, help develop more effective search 18strategies, and remove other “noisy” narratives that may prove distracting when constructing search strategies (Bettany-Saltikov, 2012; Gerberi & Marienau, 2017).

Eliminate Search Barriers

Nursing literature is replete with documentation of potential barriers to the integration of evidence-based methods into practice. The most commonly identified barriers include the perceived lack of value of EBP to practice, time constraints, lack of access to computers and databases at the point of need, limited database searching skills, and continued underutilization of evidence-based information in healthcare environments. Even trusted online resources are not as accessible or viewed as useful as consultation with a colleague as each hospital or university may have different resources available to staff (Brown et al., 2009; Pravikoff et al., 2005).

Uncertainties surrounding the research process can inhibit forward momentum. It is important to identify and manage research uncertainties early and throughout the process. Johnston et al. (2016) identified basic themes of the barriers nurses may face when conducting research. These themes, with additional “subthemes” noted, are: keeping up-to-date with the evidence, using a clinical tool, education/training, and implementation. Practicing nurses may not face approval, encouragement, or support for their research, which also leads to hesitancy to continue in the research field after their formal education.

Researchers are advised to follow a basic prescription when contemplating literature reviews: (a) spend pre-search time on discovery, planning, reflection; then (b) choose the appropriate information destinations and execute well-formulated searches; (c) critically evaluate and expand search parameters; and (d) sort, store, and organize gathered information throughout the process. Using a checklist, such as the one in Exhibit 2.2, will promote effective search habits.


Choose the Best Resources

Once a well-formulated question is created, researchers must look for the best evidence to answer the question. An understanding of the EBP hierarchy, adequate searching skills, and access to 19appropriate resources are all required to succeed. There is a remarkable amount of health research now published. With 75 trials and 11 systematic reviews published each day and an estimated 2 million-plus research papers on biomedical topics published annually, it is essential for a researcher to have a solid grasp of the resources to find the proper evidence to answer clinical questions (Bastian et al., 2010).

Start With Reviews

From an evidence-based perspective, the best bet is to start by using resources containing the secondary literature—articles that review or summarize peer-reviewed research on a topic. Keep in mind there are several types of reviews. Reviews published in the literature can be divided into two broad types: narrative and systematic. A narrative review (often referred to as simply a literature review) tends to be an article that states the current knowledge on a topic from a wide variety of sources, often by an expert in the field. This type of review is designed to be informative and can consist of nonsystematic methods of obtaining and appraising the information. A systematic review, conversely, focuses on a specific clinical topic or question, includes a thorough and explicit literature search, appraises all individual studies on a topic, and offers a conclusion to answer the clinical question. A meta-analysis is a type of systematic review that applies statistical methods to combine or pool the evidence from individual trials. Practice guidelines are commonly placed into the evidence category of “review,” but this is proper only if their statements are developed using rigorous scientific evidence (i.e., systematic reviews and randomized controlled trials).

Search the Primary Literature

Although the amount (and value) of the review literature has seen phenomenal growth in the last decade, much of the evidence, particularly in the nursing and allied health fields, still resides within the primary literature—individual reports of findings. These single studies are the building blocks from which the systematic reviews, meta-analyses, and evidence-based guidelines are built. Studies, however, are not created equal and there is a great range of publication types found in the journal literature. All levels of the evidence hierarchy from randomized controlled trials, cohort and case–control studies, to qualitative and descriptive studies are found in journals. Researchers should initiate a search in the review literature and turn to primary literature to fill in the gaps both in content and currency.

Select the Resources to Search

There are thousands of resources that cover the scholarly output of the health sciences. Some are freely available on the internet through government agencies, health organizations, or even commercial enterprises; others are restricted to individuals and/or institutions with, at times costly, subscriptions. The highest quality health research is normally found in the scholarly, peer-reviewed, journals and literature databases that cover them. Literature databases are indices of journal articles. The majority of these databases contain citations and abstracts of articles from journals covering specific topics. Some also provide either the full articles or links to providers of the articles.

It is in the best interest of the health researcher to commence with searches in the core health databases. Three literature databases considered essential for APRNs are MEDLINE (via PubMed), CINAHL (Cumulative Index to Nursing and Allied Health Literature), and the Cochrane Database of Systematic Reviews. These databases are the best starting point for both clinical and research topics in the health sciences. For a list of core database descriptions and features see Table 2.1.


21There are, of course, other databases with unique content that might be useful, if not integral, to the searcher. For instance, EMBASE, a large international health database, contains unique global literature with particularly strong coverage in topics related to drugs/pharmaceuticals; ERIC can be tapped for articles, reports, and other publications concerning education; PsycINFO, as its name implies, covers the mental health literature; and SocINDEX can be a useful resource to find evidence in sociology and related areas. Table 2.2 lists peripheral databases of interest to researchers and clinicians in nursing.

TABLE 2.2 Selected Peripheral Literature Databases



Allied and Complementary Medicine Database (AMED)

AMED covers references to articles from approximately 600 journals in three separate subject areas: professions allied to medicine; complementary medicine; and palliative care. The scope of coverage is mainly European.

British Nursing Index (BNI)

BNI is a UK nursing and midwifery database, covering more than 270 UK journals and other English-language titles, including international nursing and midwifery journals, and selected content from medical, allied health, and management titles.

Cochrane Central Register of Controlled Trials (CENTRAL)

CENTRAL includes citations and summaries of more than 1.6 million controlled trials culled from literature databases and other published and unpublished sources used to create Cochrane reviews. Subscription required.


EMBASE is a large international biomedical and pharmacological database containing more than 32 million records from 8,500 biomedical journals including more than 2,900 titles not covered in MEDLINE. EMBASE has a broad biomedical scope, with in-depth coverage of pharmacology, pharmaceutical science, and clinical research. EMBASE also includes approximately 2.4 million conference abstracts from more than 7,000 conferences.


Sponsored by the U.S. Department of Education, ERIC provides free access to more than 1.6 million records of journal articles from 1,000 journals and other education-related materials (books, research syntheses, conference papers, tech reports, policy papers, etc.) and, if available, includes links to full text.

HealthSource: Nursing/Academic Edition

This EBSCO database provides coverage of nursing and allied health and includes citation/abstracts from 840 journals and the full text of more than 320 scholarly journals.


Produced by the American Psychological Association, PsycINFO is a large behavioral science and mental health database with more than 4.7 million records from 2,500 journals, books, book chapters, and dissertations.


This large multidisciplinary database from Elsevier has over 75 million records, including citation/abstracts from 24,600 journals, 9 million conference papers, and 194,000 books. Coverage includes records from both MEDLINE and EMBASE databases.


SocINDEX is a sociology database with coverage of all subdisciplines and other related topics. It includes indexing/abstracting of 1800 core journals, as well as 320 priority coverage and 2300 selective coverage journals. There are more than 2.6 million records, going back to 1895.

22Speak the Database Language

Nurses have identified a lack of searching skills as a barrier to EBP (Fencl & Matthews, 2017). It is therefore essential for database users to develop a skill set to gain confidence and to search efficiently. This chapter proceeds with a discussion of some of the basic search concepts and tools that all researchers should understand and employ when utilizing health databases. Keep in mind that attending a continuing education (CE) session provided by a health library or institution, a consultation with a librarian, or even a few moments viewing a resource-specific tutorial will often pay great dividends.

The search terms (keywords or phrases) entered into a literature database search box will have a significant bearing on the quality of the results. Terminology in the health literature is replete with synonyms (different words, same definition) and homonyms (same word, different definition). For example, the concept cancer can be entered in a database as: cancer, tumor, malignancy, neoplasm, carcinoma, and so forth. Therefore, challenging decisions need to be made regarding the selection of appropriate terms.

In some cases, using common or everyday language is effective and appropriate. This is called free-text or keyword searching. However, searching with terms offered from a database-specific thesaurus, often referred to as a controlled vocabulary, will often prove the best way to improve the breadth and accuracy of the retrieval set.

Search Using Keywords

Keyword (free-text, natural language, common language) searches are commonly used in search boxes on the internet (e.g., Google), and all literature databases allow searchers to create search queries with keywords. Keyword searches are by nature fairly restrictive, as records retrieved by the database must have the exact term(s) entered in the search box. For example, if an author of an article uses the term ascorbic acid and the searcher enters vitamin C, the searcher would not necessarily retrieve that specific potentially relevant article.

Keyword searches can be used to find good information on a topic and are appropriate in certain circumstances. Expert searchers will often begin the process of searching a database by entering a few important keywords to obtain a quick initial retrieval set. This set is then scrutinized to uncover any appropriate additional search terms to refine the query.

Although the use of natural language may not be the best way to search a given resource (see Search Using a Controlled Vocabulary), there are techniques to improve the results of your search query:

Truncation, also called stemming, allows searching for various word endings and spellings of a keyword term simultaneously. Databases that allow truncation will designate database-specific characters, or wildcards, to initiate the truncation feature. The asterisk (*), question mark (?), and dollar sign ($) are commonly used wildcards. For example, entering communit* in the PubMed search box will retrieve records with the terms: community, communities, communitarian, communitarians, and so forth. Some resources also allow for internal (wom?n) or beginning truncation ($natal).

Phrase searching is a good way to search for specific phrases or words that are unusually formed. Many resources will allow a searcher to surround a phrase with brackets, parentheses, or quotes (depending on the resource) to retrieve only results with the exact specific phrase within the database record. This modification can reduce irrelevant results by requiring the resource to locate the component words in that specific order. For example, entering “community acquired pneumonia” in the PubMed search box will retrieve only the results containing that particular string of words.

23Search Using a Controlled Vocabulary

A controlled vocabulary is a carefully selected standardized list of terms, or thesaurus, that indexers (individuals who review articles before inclusion into a database) use to determine the main and minor topics discussed in the article. These standardized terms may or may not be the same words the author uses in their writings, but are embedded within the database record. Consequently, a searcher using a standardized or controlled term will retrieve articles on a topic, regardless of the ambiguity of terms. Many studies have shown that utilizing a controlled term will improve searches in both size and accuracy. Be aware that not all health databases use a controlled vocabulary system, and even in databases that do, many concepts do not have precise matches within the system. Also, it takes a database time to incorporate new concepts/terms into its thesaurus. For example, the term AIDS was coined in 1981, but it took more than 2 years before it was introduced into MEDLINE’s Medical Subject Heading (MeSH) thesaurus. In these cases, a searcher must resort to a keyword search.

There are several examples of a controlled vocabulary in the health literature and many are database specific:

MeSH is the National Library of Medicine’s controlled vocabulary for MEDLINE. The 2020 MeSH list contains a hierarchy of more than 27,000 descriptive terms covering virtually all medical concepts.

CINAHL uses a different set of controlled vocabulary, named CINAHL Headings. Although CINAHL Headings follow the structure of MeSH, they were developed to reflect the terminology used by nursing and allied health professionals. This controlled vocabulary thesaurus should be used when searching the CINAHL database.

Some databases have addressed the ease, and also the problems, associated with keyword searches by developing a built-in term mapping system where free-text terms are matched (mapped) against a controlled vocabulary translation table. For example, MEDLINE’s MeSH list includes over 27,000 terms, yet another 200,000 synonyms are included in the translation table. A search query with term vitamin C will be matched (and searched) with the proper MeSH term ascorbic acid. Although this is reliable for many common health terms, not all have such straightforward and successful mapping. It is very important to look for additional headings that may be synonymous with your terms because every database has numerous choices of appropriate terms.

Explode and Focus Terms

The subject headings of a controlled vocabulary are often presented in a hierarchical structure. This type of structure in MEDLINE’s MeSH thesaurus is called the “MeSH tree,” which presents broad to narrower terms. Here is the MeSH tree for the term depressive disorder:

Mood Disorders

Cyclothymic Disorder

Depressive Disorder

Depression, Postpartum

Depressive Disorder, Major

Depressive Disorder, Treatment-Resistant

Dysthymic Disorder

Premenstrual Dysphoric Disorder

Seasonal Affective Disorder

24Many databases allow searchers to explode a subject heading, which instructs the database to retrieve records with the requested subject heading as well as any more specific/narrower terms that are related to the topic. In MEDLINE, a search query with the exploded MeSH term Depressive Disorder will search not only the MeSH term Depressive Disorder, but also the terms Depression, Postpartum; Depressive Disorder, Major; Depressive Disorder, Treatment-Resistant; Dysthymic Disorder; Premenstrual Dysphoric Disorder, and Seasonal Affective Disorder. Be aware that when searching using MeSH terms, PubMed automatically explodes the MeSH term(s). It is possible to prevent that by selecting the box titled Do not include MeSH terms found below this term in the MeSH hierarchy.

The major command instructs the database to retrieve only those articles in which the subject term selected is considered to be a primary focus of the article. This command narrows your search by eliminating articles that peripherally discuss the topic of the subject heading. In PubMed’s MeSH one can apply the focus command by checking the Restrict to MeSH Major Topics box and in CINAHL by checking the Major Concepts box within CINAHL Headings.

Combine Concepts (Boolean Operators)

Boolean logic defines the relationship between terms in a search. There are three Boolean operators: AND, OR, NOT. Database searchers can apply these operators to create broader or narrower searches:

AND combines search terms so that the retrieval set contains all of the terms. The AND operator is generally placed between different concepts. For example, the search St John’s Wort AND Depression will retrieve results containing both terms.

OR combines search terms so that the retrieval set contains at least one of the terms. The OR operator is generally placed between synonyms of the same concept. For example, St John’s Wort OR Hypericum will retrieve results containing either term.

NOT excludes search terms so that the retrieval set will not contain any of the terms that follow the operator NOT. For example, St John’s Wort NOT Adolescent will retrieve results containing the term St John’s Wort without the term Adolescent. Searchers should apply the NOT operator with caution, since it often excludes relevant results with only a passing mention of the term NOTed out.

For more efficient searching using Boolean operators, parentheses (brackets) should be used to nest search terms within other search terms. By nesting terms, searchers can specify the order in which the database interprets the search. It is recommended that synonyms (i.e., terms ORed together) should be nested. For example, (St John’s Wort OR Hypericum) AND (Depression OR Depressive Disorder).

Advanced Versus Basic Search Modes

Several resources offer the searcher an option of using a basic search interface with limited and rudimentary options for conducting and refining a search, or a more advanced mode that will provide more sophisticated search features and allow searchers to employ many of the techniques discussed in this section. The advanced search mode is the only choice for earnest researchers.

Utilize Filters and Limits

To aid in retrieval relevancy and precision, databases may offer options to filter and/or limit searches by certain parameters. Several databases have devised valuable and effective filters for 25researchers and clinicians specifically for finding the evidence to answer clinical questions. One example is PubMed’s Clinical Queries, which offers essential built-in evidence-based medicine search filters to retrieve systematic reviews (and meta analyses, evidence-based guidelines, etc.) and individual studies at the highest tier of the evidence hierarchy (e.g., randomized controlled trials for therapy scenarios). Other examples include the Evidence-Based Practice or the Systematic Review publication type limit within CINAHL. These filters can be particularly helpful in finding the best evidence on a topic.

Literature databases also offer several ways to limit the retrieval set. Common limits include:

Date: Allows searchers to restrict the publication dates of the articles retrieved. Keep in mind that newer literature is not always better.

Language: Databases include articles from many different countries and languages, so it may be helpful to limit the results of a search to a specific language.

Publication Type: Journal articles are not created equal. Case reports, cohort studies, controlled trials, editorials, systematic reviews, comments, practice guidelines, audiovisuals, book chapters, dissertations, and so on, are found in the journal literature.

Age: Some databases offer limits by specific age groups. For example, by selecting the Infant limit in CINAHL or MEDLINE, the majority of articles concerning infancy will be retrieved. However, articles that include additional age groups will also be retrieved.

Full Text: Several databases include a small selection of free full-text (entire) articles. Use of the full-text limit will restrict the results to only items that include, or provide links to, the full text. Selecting this option will often greatly reduce the retrieval set and give no guarantee in the quality of items retrieved. Many health organizations, centers, academic institutions, and so on, have the ability to embed a much larger set of full-text content into a database that would not be picked up by the generic full-text option. If the purpose of a literature search is to produce a comprehensive set of relevant articles, this limit should not be applied. However, if the purpose is simply to get a quick grasp of a clinical topic, this option might prove useful since whole articles could be obtained.


Target Health Websites for Guidelines, Reviews, and Reports

There are plenty of health-related websites that provide quality information for both researchers and clinicians. It is often necessary to venture beyond the literature databases to find guidelines, reports, consensus statements, and other documents not published in the commercial literature. Table 2.3 presents a selective list of valuable sites for EBP.

Some look and act much like commercial literature databases and provide access to information created by others (meta-sites). TRIP database, for example, is a sophisticated tool that searches dozens of evidence-based resources in addition to the millions of articles in MEDLINE. SUMSearch 2 also searches the internet for evidence-based medical information by scanning literature databases and high-impact medical journals, and employs a unique method of searching and filtering for the best results.

Whereas large meta-sites include citations from a wide variety of documents, others are designated as repositories for specific publication types. Practice guidelines are valuable components in 26the delivery of evidence-based healthcare practice. Consequently, researchers should have some familiarity with sites specifically focusing on guidelines, such as the ECRI Guidelines Trust™.

TABLE 2.3 Select Examples of Websites



ACP Clinical Guidelines

ACP Clinical Guidelines cover many areas of internal medicine, including screening for cancer or other major diseases, diagnoses, treatment, and medical technology. Included are Clinical Practice Guidelines, Clinical Guidance Statements, and Best Practice Advice.

Agency for Healthcare Research and Quality

Evidence-Based Practice Centers

A collection of high-quality reports, reviews, and technology assessments based on rigorous, comprehensive syntheses and analyses of the scientific literature on topics relevant to clinical, social science/behavioral, economic, and other healthcare organization and delivery issues.

Agency for Healthcare Research and Quality

U.S. Preventive Services Task Force

The U.S. Preventive Services Task Force is an independent panel of experts in primary care and prevention that systematically review the evidence for effectiveness and develop recommendations for clinical preventive services.

American Heart Association Scientific

Statements and Guidelines

A collection of AHA’s scientific statements and practice guidelines that are published in Circulation; Stroke; Arteriosclerosis, Thrombosis, and Vascular Biology; Hypertension; Circulation Research; or other journals.

CDC Infection Prevention & Control Guidelines & Recommendations

This site includes an overview of how infections spread, ways to prevent the spread of infections, and more detailed recommendations by type of healthcare setting.

The Community Guide

Developed by the nonfederal Task Force on Community Preventive Services, whose members are appointed by the Director of the Centers for Disease Control and Prevention (CDC), The Community Guide summarizes what is known about the effectiveness, economic efficiency, and feasibility of interventions to promote community health and prevent disease.

ECRI Guidelines Trust™

ECRI Institute, an independent, nonprofit patient safety organization, developed this new resource in response to urgent pleas from healthcare professionals after substantial federal funding cuts forced the Agency for Healthcare Research and Quality (AHRQ) to shut down the National Guideline Clearinghouse™ (NGC). ECRI had developed and maintained the NGC website for 20 years.

Guideline Central

Guideline Central is dedicated to providing healthcare professionals with evidence-based clinical decision-support tools that are current, practical, and easily accessible. It partners with over 35 medical societies and government agencies to provide quick-reference tools that physicians can rely on for credible guidance in the management of a medical condition.

Healthy People 2020

Healthy People 2020 is the product of an extensive stakeholder feedback process that is unparalleled in government and health. It integrates input from public health and prevention experts, a wide range of federal, state and local government officials, a consortium of more than 2,000 organizations, and perhaps most importantly, the public.

27Infectious Diseases Society of America Practice Guidelines

Includes standards, practice guidelines, and statements developed and/or endorsed by the IDSA.

The Joanna Briggs Institute

JBI is an initiative of the Royal Adelaide Hospital and the University of Adelaide. The Institute provides “a collaborative approach to the evaluation of evidence derived from a diverse range of sources, including experience, expertise and all forms of rigorous research and the translation, transfer and utilization of the ‘best available’ evidence into healthcare practice.” Many resources are available only to member institutions, although selected systematic reviews and best practices information sheets are available to nonmembers.

National Cancer Institute Clinical Trials

Allows users to search and browse recent clinical trial results by type of cancer or topic or search NCI’s list of thousands of clinical trials now accepting participants. Also included are educational materials about clinical trials, a list of noteworthy clinical trials, and more information for research teams interested in conducting clinical trials.

Nursing Best Practice Guidelines

Presents best practice guidelines for client care developed for Ontario Nurses. Includes almost 50 published guidelines as well as a Toolkit and an Educator’s Resource to support implementation.

SUMSearch 2

A free meta-search engine for evidence-based medical information, scanning databases (MEDLINE, DARE, and National Guidelines Clearinghouse) as well as various high-impact medical journals. To automate searching, SUMSearch 2 combines meta- and contingency searching. Meta-searching is designed to scan multiple databases and sites simultaneously, and returns one single retrieval document to the user. If a high number of results are obtained, more restrictive searches (called contingency searches) are conducted by activating additional filters. Conversely, if the result is small, more databases are added to the search.

TRIP Medical Database

A free meta-search engine providing quick access to evidence-based and other high-quality medical information resources via a single interface. TRIP identifies/searches numerous internet resources that allow access to their content such as MEDLINE, Cochrane, National Guidelines Clearinghouse, ACP Journal Club, and top peer-reviewed journals. These resources are then categorized by type: Evidence-Based Synopses, Clinical Questions, Systematic Reviews, Guidelines, Core Primary Research, E textbooks, and Calculators.

Virginia Henderson Global Nursing

e-Repository (Sigma Repository)

This repository is an online digital service that collects, preserves, and disseminates digital materials in both abstract and full-text format without charge. Submissions may be made by individual nurses, nursing students, and nursing organizations and may include preprints, working papers, theses, dissertations, conference papers, presentations, faculty-created learning objects, data sets, etc.

ACP, The American College of Physicians; AHA, American Heart Association; IDSA, Infectious Diseases Society of America; JBI, The Joanna Briggs Institute; NCI, National Cancer Institute.

28Government agencies and professional associations that have developed clinical guidelines and practice statements may include them on their websites. Examples of this include standards, practice guidelines, statements, and clinical updates available online from the Infectious Diseases Society of America and the American Heart Association.

Websites of health agencies and associations organized around specific diseases or conditions also frequently post valuable reviews, reports, and studies that may or may not be included in the pages of journals. The website for the Agency for Healthcare Research and Quality delivers agency-funded, evidence-based research reports on clinical topics, healthcare services, and research methodologies. The website of the National Cancer Institute provides summaries of recently released results from clinical trials.

Search the Whole Internet

There is never one perfect location to find information on a health topic. Some people quickly turn to the ease of the internet as a starting place, which can be quite useful if you know where to look or how to search for pertinent and reliable information. The capability for “publishers”—whether they are healthcare institutions, corporate entities, government agencies, even individuals—to quickly and inexpensively publish permits immediate information transfer to the internet user. This also allows groups to distribute potentially important relevant information that may go unpublished through commercial channels. This type of literature is often referred to as the grey literature and can include scientific and technical reports, guidelines, care plans, patent documents, conference papers, internal reports, government documents, newsletters, factsheets, and theses.

Third-party informational sites such as Wikipedia are quickly becoming the initial stopping point for information on diagnoses, treatments, and prognoses of conditions. The use of these sites has tended to be negative in nature due to their open editing and lack of verification of research and/or resources. Wikipedia, for example, continues to be both a positive and negative resource to use during a research project. Aibar et al. (2015) conducted a large study looking at the use of Wikipedia and what faculty thought about it as a teaching tool. Aibar et al.’s study found that “academic disciplines [were] a key factor in explaining attitudes towards Wikipedia. This study also showed that age correlates with having a more negative view and that faculty who frequently use other online resources are more sceptical [sic] of Wikipedia” (p. 670). As with any online resource, the researcher should use critical analysis to determine the validity and reliability of the information contained within and not automatically assume the information is correct (London et al., 2019).

The information available via the internet is neither entirely trustworthy nor well organized. There are numerous popular search engines that scour the internet to retrieve materials that match keywords entered in the search box. Search engines use specific algorithms to sort retrieved results and in many cases retrieval order depends on a mixture of keyword matches, currency, and other factors (not necessarily quality of content). To eliminate some of the vagaries of internet searching, there are techniques to improve the quality and reliability of the retrieval set. The first is to try a selective search engine. A good example of a selective multidisciplinary search engine is Google Scholar (, which restricts an internet search to “scholarly” publications such as journal articles, technical reports, preprints, theses, books, and vetted web pages from academic publishers, professional societies, preprint repositories, universities, and other scholarly organizations. Another good technique is to seek and employ search tools or an advanced search option, which may offer numerous options for making searches more precise and getting more 29reliable results. Do keep in mind, however, that much of the internet is not peer-reviewed or vetted in any way, so the searcher carries the burden of evaluating the quality and accuracy of the information presented. Strategies to assess website quality are presented in Exhibit 2.3.

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Oct 17, 2021 | Posted by in NURSING | Comments Off on Searching for Evidence

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