Ch. 7 Preliminary Steps in Research

Purposes of Research Literature Reviews

- integrate research evidence to sum up what is known and what isn't - lay the foundation for new studies - help researchers to interpret their findings - *quantitative* studies use them to help shape research questions, suggest appropriate methods, & point to a conceptual framework - opinions about lit. reviews in *qualitative* studies differ - grounded theory researchers collect data before reviewing the lit. - phenomenologists read the lit. at the beginning of the study - ethnographers familiarize with the lit. first to help shape their cultural problem before going into the field

Major Steps & Strategies in Doing a Literature Review

1) A reviewer must start with a question, such as an EBP question, or a question for a new study 2) Reviewer must then gather, analyze, & interpret the info. & summarize the findings in a written product A high quality review should be unbiased, thorough, & up-to-date; should also be systematic & reproducible Doing a lit. review is like undertaking a qualitative study in regards to analyzing the data & looking for important themes

Critiquing Research Literature Reviews

1) Does the review seem thorough & up-to-date? Does it include major studies on the topic? Does it include recent research? 2) Does the review rely on appropriate materials (ex: mainly on research reports, using primary sources)? 3) Is the review merely a summary of existing work, or does it critically appraise & compare key studies? Does the review identify important gaps in literature? 4) Is the review well organized? Is the development of ideas clear? 5) Does the review use appropriate language, suggesting the tentativeness of prior findings? Is the review objective? Does the author paraphrase, or is there an overreliance on quotes from original sources? 6) If the review is in the introduction for a new study, does the review support the need for the study? 7) If it is a review designed to summarize evidence for clinical practice, does the review draw appropriate conclusions about practice implications? In assessing a literature review, the overarching question is whether it summarizes the current state of research evidence If the review is written as part of an original research report, an equally imp. question is whether the review lays a solid foundation for the new study

Style of a Research Review

A lit. review should include opinions sparingly, & should explicitly reference the source (reviewers own opinions don't belong in a review, with the exception of assessments of study quality) Hypotheses aren't proved or verified, they are *supported* by research findings

Wildcard Character

A symbol, such as */$, depending on the search program, which allows you to search for multiple words with the same root It is typically inserted after a truncated (shortened) root Ex: if you put in nurs*, the results would show up with nursing, nurses, nurse, etc. However, this may turn off mapping & result in a textword search exclusively

Literature Review

A written summary of the state of evidence on a research problem Tells readers about current knowledge on a topic & illuminates the significance of the new study; often intertwined with the problem statement as part of the argument for the study

2 Important Electronic Databases

CINAHL - aka Cumulative Index to Nursing and Allied Health Literature MEDLINE - Medical Literature On-Line Other databases include: - Cochrane Database of Systematic Reviews - Web of Knowledge (useful for descendancy search strategy bc of its strong citation indexes) - Scopus - EMBASE (Excerpta Medica database)

Boolean Operators

Can be used to expand/restrict a search Ex: if you wanted citations on lung cancer & smoking, you could enter the following: lung cancer AND smoking This would restrict the search to citations with both lung cancer & smoking as textwords or subject headings Using the term "OR" would retrieve all references with either term

CINAHL Database

Covers references to hundreds of nursing & allied health journals, as well as to books, book chapters, & dissertations; contains more than 1 million records Provides info, for locating references (ex: the author, title, journal, year of publication, volume, & page #s) & abstracts for most citations Sources should indicate: - name of the journal - year + month of publication - volume - issue - page numbers - # of cited references Major + minor subjects could have been used in a subject heading search to retrieve the info. you were searching for as well You would base the reference's pertinence to your inquiry after reading the abstract

MEDLINE Database

Developed by the U.S. National Library of Medicine; the premier source for bibliographic coverage of the biomedical literature Can be accessed for free at www.ncbi.nlm.nih.gov/PubMed Uses controlled vocabulary called *MeSH* (medical subject headings) to index articles which provides a consistent way to retrieve info. that may use diff. terminology for the same concepts MeSH subject headings may overlap with, but aren't identical to subject headings in CINAHL

Types of Information to Seek for a Research Review

Findings from prior studies are the most imp. type of info. If preparing a lit. review, you should rely mostly on *primary sources* (descriptions of studies written by researchers who conducted them) Lit. reviews are secondary sources (descriptions of studies prepared by someone else) However, if composing your own lit. review, don't use secondary sources bc they aren't detailed enough & are seldom completely objective Nonresearch references: opinion articles, case reports, & clinical anecdotes (these may broaden topic understanding but have limited utility in research reviews bc they don't address the central question of: what is the current state of evidence on this research problem?)

Getting Started With an Electronic Search

Identify which keywords (a word/phrase that captures the key concepts in your question) you want to launch the search with *Quantitative* study keywords are usually the independent/dependent variables (ex: the I + O of PICO) & perhaps the population *Qualitative* study keywords are the central phenomenon & the population The indexing systems have specific subject headings (subject codes) & a hierarchical organizational structure with subheadings bc all citations in a database are coded in order to be retrieved *Mapping* is a feature that allows you to search for topics using your own keywords, rather than the exact subject heading A textword search looks for your keyword in the text fields of the records (in the tile + abstract) Putting quotation marks around a phrase can force a textword search, which yields citations in which the exact phrase appears in text fields

Documentation in Literature Review

It is wise to document your search actions + results Make note of databases searched, keywords used, limits instituted, studies used to launch a "descendancy" search, & any other info. that would help you keep track of what you already did You can do this by printing your search history from the databases

Content of the Written Literature Review

It should provide readers with an objective, well-organized synthesis of current evidence on a topic Should not be a series or quotes/abstracts or explain what the researchers have done It should summarize & critically evaluate the evidence to reveal the current state of knowledge on a topic Findings should be summarized in your own words, unbiased as possible (inconsistent results should be analyzed & the supporting evidence evaluated objectively), & should conclude with a summary of current evidence on the topic (recap key findings, assess their credibility, & point out gaps in the evidence) If it for a new study, the summary should demonstrate the need for research & clarify the context for any hypotheses

Analyzing & Synthesizing Information

Once relevant studies have been retrieved, abstracted, & critiques, the info. has to be analyzed + synthesized Focus is on the identification of important *themes* A thematic analysis involves detecting patterns + regularities, as well as inconsistencies 3 themes: *Substantive themes* -- What is the pattern of evidence - what findings predominate? How much evidence is there? How consistent is the body of evidence? What gaps are there in the evidence? *Methodologic themes* -- What methods have been used to address the question? What strategies have not been used? What are major methodologic deficiencies & strengths? *Generalizability/transferability themes* -- To what types of people or setting does the evidence apply? Do the findings vary for diff. types of people (ex: men vs. women) or setting (ex: urban vs. rural)? Usually, substantive themes are of greatest interest

Screening & Gathering References

References that have been identified in the search need to be screened for *accessibility* (will I be able to retrieve the article?) & *relevance* You can usually surmise a reference's relevance by reading the abstract

Developing a Search Strategy

Search for evidence in bibliographic databases *Ancestry approach* -- aka footnote chasing; citations from relevant studies are used to track down earlier research on which the studies are based (the "ancestors") *Descendancy approach* -- find a pivotal early study & search forward in citation indexes to find more recent studies (the "descendents") that cited the key study It is always best to limit + refine your search criteria (ex: research within the past 15 years)

Organizing the Review

When literature on a topic is extensive, it is useful to summarize info. in a *table* (columns with headings like: author, sample characteristics, design, key findings) that allows you to make sense of a mass of info. An *outline* is helpful as well to organize the review into a meaningful & understandable flow The goal is to structure the review to lead logically to a conclusion about the state of evidence on the topic If some references don't fit the outline or anywhere, just omit them -- the # of references is less important than their relevance

Abstracting & Recording Information

You need a strategy to organize & make sense of the info. in the articles you deem as useful For simple lit. reviews, you can make notes about key features of the retrieved studies & to base your review on those notes If the lit. review is complex, it would be best to incorporate a formal system of recording info, of each study (code the characteristics of each study & then record codes in a set of matrices) Copy + paste each abstract & citation info. from the database into a word doc., then the bottom of each page could have a "miniprotocol" for recording imp. info. that you want to record consistently across studies

Evaluating Studies for a Review

You need to evaluate the quality of each study so that you could draw conclusions about the overall evidence & about gaps in the evidence base Critiques for a lit. review tend to focus on methodological aspects to answer a broad question: to what extent do the findings reflect the truth (the true state of affairs), or conversely, to what extent to flaws undermine the believability of the evidence? The "truth" is most likely to be discovered when researchers use powerful designs, good sampling plans, high-quality data collection procedures, & appropriate analyses

Summary Points

● A research literature review is a written summary of the state of evidence on a research problem. ● The major steps in preparing a written research review include formulating a question, devising a search strategy, searching and retrieving relevant sources, abstracting and encoding information, critiquing studies, analyzing and integrating the information, and preparing a written synthesis. ● Research reviews rely primarily on findings in research reports. Information in nonresearch references (e.g., opinion articles, case reports) may broaden understanding of a problem, but has limited utility in summarizing evidence. ● A *primary source* is the original description of a study prepared by the researcher who conducted it; a *secondary source* is a description of a study by another person. Literature reviews should be based on primary source material. ● Strategies for finding studies on a topic include the use of bibliographic tools, but also include the ancestry approach (tracking down earlier studies cited in a reference list of a report) and the descendancy approach (using a pivotal study to search forward to subsequent studies that cited it.) ● Key resources for a research literature search are the *bibliographic databases* that can be searched electronically. For nurses, the *CINAHL* and *MEDLINE®* databases are especially useful. ● In searching a bibliographic database, users can do a keyword search that looks for terms in text fields of a database record (or that maps keywords onto the database's subject codes), or can search according to the subject heading codes themselves. ● Retrieved references must be screened for relevance, and then pertinent information can be abstracted and encoded for subsequent analysis. Studies must also be critiqued to assess the strength of evidence in existing research. ● The analysis of information from a literature search essentially involves the identification of important *themes* —regularities and patterns in the information. ● In preparing a written review, it is important to organize materials coherently. Preparation of an outline is recommended. The reviewers' role is to point out what has been studied, how adequate and dependable the studies are, and what gaps exist in the body of research.