Chapter 3 Lecture Research Techniques: For the Health Sciences Fifth Edition © 2014 Pearson Education, Inc. Critical Review of the Literature and Information Sources R. Eric Heidel, PhD University of Tennessee Graduate School of Medicine

Review of the Literature Relevant Literature –provides a framework for the research question, hypothesis, and setting of the problem © 2014 Pearson Education, Inc.

Purposes of the Review The general purpose is to gain an understanding of previous work and to generate new ideas and concepts. The process can additionally help the investigator to: 1.develop an understanding and grounding in theory 2.define the problem 3.review the procedures and instruments used 4.originate new ideas rather than repeat work already accomplished 5.use the recommendations for further research 6.critique relevant studies © 2014 Pearson Education, Inc.

The Importance of the Research Question The key words used in any literature search are the basis for a successful review of the literature. Clinically based questions demand timely answers and the best available evidence. The best evidence requires the most answerable clinical questions. © 2014 Pearson Education, Inc.

The Importance of the Research Question (cont'd) The PICO acronym is used as a framework for developing research questions and for conducting literature searches –P—patient or problem –I—intervention –C—comparison –O—outcome © 2014 Pearson Education, Inc.

Steps in the Review Process Steps to consider when beginning a review of the literature: 1.reading background information 2.gathering the necessary tools 3.listing key words 4.checking preliminary sources, including databases 5.conducting a computer search 6.determining what to read 7.determining the level of evidence 8.finding shortcuts to determining the level of evidence © 2014 Pearson Education, Inc.

Reading Background Information Primary Sources –written by someone who has observed or participated in an event –must be read –include journals, final reports, or books that contain original research –government publications are good primary sources for many health topics © 2014 Pearson Education, Inc.

Reading Background Information (cont'd) Secondary Sources –textbooks written by someone who has not directly observed the described event –usually have a bibliography, which provides the reader with relevant primary sources © 2014 Pearson Education, Inc.

Gathering the Necessary Tools Systematically gathering data will keep you organized and will prevent you from having to redo what you have already done. Bibliography Index –Filing systems may be arranged by: 1.authors' names, in alphabetical order 2.date, with the most recent work first 3.subheading 4.level of evidence –A combination of these techniques could also be used © 2014 Pearson Education, Inc.

Listing Key Words After collecting the background information, you will have an idea of the topic area and be able to generate key words. Key words or phrases are necessary because almost all health science sources are organized by subject, and you should have a list of key words to search the computer databases. © 2014 Pearson Education, Inc.

Checking Preliminary Sources Preliminary sources –help the investigator locate primary sources reference books indices abstracts guidebooks periodicals © 2014 Pearson Education, Inc.

General Indexing and Abstracting Services There are several databases available through online computer services at most libraries. A growing number of these databases contain full text or direct you to websites with full text of the document. © 2014 Pearson Education, Inc.

General Indexing and Abstracting Services (cont'd) Databases: –BIOETHICSLINE –Biological Abstracts –CINAHL (Cumulative Index to Nursing and Allied Health Literature) –ERIC –HAPI (Health and Psychosocial Instruments) –MEDLINE –MEDLINEplus –National Library of Medicine –PsycINFO –Social Work Abstracts –TOXNET © 2014 Pearson Education, Inc.

Evidence-Based Full-Text and Abstracting Services These database services can save the health researcher an immense amount of time when seeking high-quality evidence-based information. Examples: –Bandolier –Cochrane Library –Database of Abstracts of Reviews of Effectiveness (DARE) –National Guideline Clearinghouse (NGC) –PedsCCM Evidence-Based Journal Club –PubMed –SUMSearch –TRIPdatabase (Turning Research into Practice) © 2014 Pearson Education, Inc.

Government Documents These listings can be accessed as government documents using the website of the Centers for Disease Control for the National Center for Health Statistics ( –National Center for Health Statistics (NCHS) –National Health and Nutrition Examination Survey (NHANES) –National Health Care Survey (NHCS) –National Health Interview Survey (NHIS) –National Immunization Survey (NIS) –National Survey of Family Growth (NSFG) –National Vital Statistics System (NVSS) © 2014 Pearson Education, Inc.

Conducting a Computer Search: Finding the Evidence Using the computer search will enhance your ability to check the preliminary sources. Full-text electronic journals and abstracts are available using a literature search engine. Some online resources are available strictly through university libraries and public libraries. The printouts of the list of citations will include a full bibliographic entry that can later be converted to a bibliographic database of your own. © 2014 Pearson Education, Inc.

How to Conduct a Computer Search 1.Specify the research problem. 2.Select the databases. 3.Select the descriptors. 4.Conduct the search. 5.Increase sensitivity and specificity. 6.Review the citation list. © 2014 Pearson Education, Inc.

Determining the Level of Evidence As a general rule, useful information must have three attributes: 1.It must be relevant to the research effort. 2.It must be correct. 3.It must require little effort to procure. The formula is: level of evidence = (relevance x validity) work © 2014 Pearson Education, Inc.

Determining the Level of Evidence (cont'd) Relevance –This component begins with the applicability of the evidence to your problem. –Information must be critically appraised or evaluated for its validity and research usefulness. © 2014 Pearson Education, Inc.

Determining the Level of Evidence (cont'd) Validity –Health literature can be grouped into a pyramid of evidence Categories range single studies that provide little evidence to systematic reviews that collect and describe all relevant studies addressing the research question. Researchers, among others, want to base their decisions on the best evidence available. © 2014 Pearson Education, Inc.

Haynes's 5 Ss © 2014 Pearson Education, Inc.

Determining the Level of Evidence (cont'd) Work –In health care, there are several databases that allow the researcher to search by level of evidence. –Databases that conduct systematic reviews are preferred because they locate, appraise, and synthesize evidence from scientific studies in order to provide informative empirical answers to scientific research questions. –Systematic reviews adhere to a strict scientific design in order to be more comprehensive, minimize bias, and ensure reliability. © 2014 Pearson Education, Inc.

Determining the Quality of Evidence The GRADE system rates the quality of evidence and grades the strength of recommendations for systematic reviews, health technology assessments, and clinical practice guidelines looking at alternative management options. The system classifies the quality of evidence as high, moderate, low, or very low according to factors that include the study methodology, consistency, and precision of the results and directness of the evidence. A key in using GRADE is a well-worded clinical question with possible outcomes. © 2014 Pearson Education, Inc.

Writing the Section on Related Literature Relating the Review –Information in the literature review should always relate to the introductory material. –This will enable the introduction to flow coherently and present an organized approach to theory and research related to your topic. –Literature should be related to the purpose of the study, the generated hypotheses, and the population in question. © 2014 Pearson Education, Inc.

Writing the Section on Related Literature (cont'd) Developing a Plan –Subheadings are usually based on the variables and their relationship to the problem of your study. –Begin each subtopic with an introductory sentence and end with a summarizing section. © 2014 Pearson Education, Inc.

Writing the Section on Related Literature (cont'd) Summarizing –This section recaps the relevant information relating to theory, previous research, new insights, and the stated hypotheses. –Generally, one or two paragraphs should suffice, if presented cogently. © 2014 Pearson Education, Inc.