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Getting Started: What’s Out in the Literature and Is It Any Good?. Susan B. Fowler, PhD, RN, CNRN, FAHA. Literature. Research Critique. Is not synonymous with “criticize” Examines the strengths, weaknesses, meaning, and significance of the study (substantive and theoretical dimensions)
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Getting Started: What’s Out inthe Literature and Is It Any Good? Susan B. Fowler, PhD, RN, CNRN, FAHA
Research Critique • Is not synonymous with “criticize” • Examines the strengths, weaknesses, meaning, and significance of the study (substantive and theoretical dimensions) • Be objective and realistic in identifying the study’s strengths and weaknesses
Important Points • All studies have weaknesses or flaws • Research is critiqued to broaden understanding, improve practice, and provide background for conducting a study • The critique process involves comprehension, comparison, analysis, and evaluation
Cochrane Systematic Reviews • Cochrane Librarywww3.interscience.wiley.com/cgi-bin/mrwhome/106568753/HOMEThe Cochrane Collaboration. Oxford: Update Software; 1996-. Updated quarterly. • Cochrane Database of Systematic Reviews (Cochrane Reviews) • 'Gold Standard' for high-quality systematic reviews • Full-text included in Cochrane Library • Cochrane Reviews includes complete reviews and protocols (reviews that are still in progress) • Cochrane Reviews abstracts are in PubMed
More Reviews • Database of Abstracts of Reviews of Effects (Other Reviews - DARE) • prepared by the National Health Service Centre for Reviews and Dissemination, University of York, England • Complements the Cochrane Reviews by offering a selection of quality assessed reviews in those subjects where there is currently no Cochrane review • Brief critical appraisals of previously published reviews of the effects of health care • Structured abstracts, not full-text • DARE not indexed in PubMed, but original research articles may be • Also available at no charge on the web from University of York | www.crd.york.ac.uk/crdweb/
Other Systematic Reviews and Meta-analyses • PubMed MEDLINE - Systematic Reviews | www.ncbi.nlm.nih.gov/entrez/query/static/clinical.shtml • access: part of PubMed's Clinical Queries (linked on PubMed Home and Advanced Search pages) • Identifies systematic reviews and other similar types of studies found in biomedical journals included in PubMed database • No evaluation of comparative quality of different reviews on a topic • Abstracts supplied by authors/journals. No separate evaluation of quality of research • Identify systematic reviews in the biomedical area - gathers together much larger collection than other evidence-based practice resources
Evidence Guidelines/Summaries • BMJ Clinical Evidence | www.clinicalevidence.com/ • Compendium of evidence on the effects of clinical interventions • Summarizes the current state of knowledge, including knowns and unknowns, based on thorough search • Categorizes interventions as beneficial, likely beneficial, no known benefit, harmful ... • DynaMed | www.ebscohost.com/dynamed • Best available evidence summaries for nearly 2000 topics • Clinical reference tool developed for use at the 'point-of-care' • Outline format to quickly identify key conclusions • Updated daily • Other Resources • USPSTF Guidelines | www.ahrq.gov/clinic/prevenix.htm • AHRQ Evidence Reports | www.ahrq.gov/clinic/epcix.htm • FPIN Clinical Inquiries included in Journal of Family Practice | www.jfponline.com and American Family Physician | www.aafp.org/afp/
RCTs, Case Cohorts, Control Studies • PubMed | (pubmed.gov) • note: Filtered by publication type, but not quality • Clinical Queries - Uses preconfigured search strategies to retrieve research-based citations on clinical topics in the areas of therapy, diagnosis, etiology, or diagnosis • Use Limits to search by specific publication type (e.g. meta-analysis, randomized controlled trial, review) • Cochrane Library | www3.interscience.wiley.com/cgi-bin/mrwhome/106568753/HOMEThe Cochrane Collaboration. Oxford: Update Software; 1996-. Updated quarterly. • Cochrane Central Register of Controlled Trials (Clinical Trials) • Bibliography of controlled trials as part of an international effort to hand search the world's journals • Includes reports published in conference proceedings and in many other sources not in PubMed or other bibliographic databases
Content of Research Reports • The Abstract • The Introduction (review of the literature, theoretical framework, significance of and need for the study) • The Methods Section • The Results Section • The Discussion Section • The References
The Beginning • The title • Could you tell what the article was about by reading the title? • The abstract • Includes a brief description of the problem • How the study was done (methodology) • The results • Conclusions
Next Steps • The Problem • Is it clear what the problem the authors are trying to solve? • Review of the Literature • Do the articles relate to the problem? • Is it organized, broad to specific? • Does it tell a story? • Comprehensive and current? What years are covered in the ROL? • Research Question/Aim/Purpose/Hypothesis • Do authors pose a research question or hypothesis? • Is it explicitly stated what the aim or purpose of the study is? • Design • Is the design stated? • Does the design flow from the research question or aim? • Did the authors explain why they choose this research design?
Design Quantitative Qualitative • Analysis of numerical data • Experimental • Quasi-experimental • Comparative • Longitudinal • Correlational • Analysis of data such as words (e.g., from interviews), pictures (e.g., video), or objects (e.g., an artifact) • Grounded theory - social processes • Phenomonology – lived experience • Ethnography – culture • Historical
The Journey Continues • Sample • Is the population described? • Is the sample method, or how the sample was chosen described? • Is the sample size right for the analysis? Was a power analysis done to determine sample size? • Were standards for protection of human subjects discussed? • Tool • Was the tool created by the authors or already established? • Is a copy of the tool included in the article? • Is reliability discussed? • Is validity discussed?
Tool, Instruments, Questionnaires, and More Validity Reliability • Extent to which the tool measures what it was intended to • Content • Criterion related • construct • Results are repeatable and consistent • Internal consistency • Test-retest • Inter-rater
Power • The probability that a statistical test will detect a significant difference that exists - the risk of a Type I error can be calculated using power analysis. • Level of significance • Sample size • Power - acceptable level is .80 • Effect size - the degree to which the null hypothesis is false
Effect Size • An estimate of how large the treatment effect is, that is how well the intervention worked in the experimental group compared to the control group (intervention studies) • The larger the effect size, the stronger are the experimental intervention’s effects. • Effect size for intervention studies: • .2 = small effect • .5 = medium effect • .8 = large effect
Getting Closer to the End • Methodology • Are methods of data collection sufficiently described? • Is the time frame when the study occurred described? • Data Analysis • Is information presented sufficient to answer the research question(s)? • Were statistical tests used to analyze the data? • Were values obtained from the analysis? • Was statistical significance reported? • Are the results explained? • Are tables and figures easy to understand and informative?
Confidence Intervals • Probability that a value will fall within a range of variables • The larger the CI the less precise the measurement of that variable • A very wide interval may indicates that more data should be collected before anything very definite can be said about the parameter • 95% CI most common
The End • Discussion • Is a discussion section presented? • If yes, are the results compared with the literature review? • Conclusions • Are conclusions clearly stated? • Are conclusions directly related to the results? • Do the findings add to the present nursing knowledge? • Are study limitations identified? • Did authors make recommendations for further research? • Carlson, J. (1999). J Emerg Nurs, 25, 330-332.
References • Relevance (extent to which the reference bears on the research question) • Primary sources (descriptions of studies written by the researchers) • Secondary sources (descriptions of studies written by someone other than the original researcher) • Opinion and anecdotal
Level of Significance • The researcher does not know when an error in statistical decision making has occurred. The researcher can control the risk of making a Type I Error by setting the level of significance. • Level of Significance (alpha level) is the probability of making a Type I Error or the probability of rejecting a true null hypothesis.
Level of Significance • Usual level set at .05 (willing to accept the fact that if the study were carried out 100 times, the decision to reject the null hypothesis would be wrong 5 times) • If researcher wants to have smaller risk of falsely rejecting null hypothesis, set at .01. • Decreasing risk of making Type I Error increases risk of Type II Error. • Findings are significant or not significant.
Clinical Significance • Related to practical importance of the findings • No common agreement in nursing about how to judge clinical significance • Effect size? • Difference sufficiently important to warrant changing patient care?
Clinical Significance • Who should judge clinical significance? • The patients and their families? • The clinician or researcher? • Society at large? • Clinical significance is ultimately a value judgment
Research Journals • Examples of peer reviewed / refereed journals: Nursing Research, Advances in Nursing Science, Applied Nursing Research, Clinical Nursing Research, Western Journal of Nursing Research • Example of Peer Reviewed online resource: Medscape • Peer Review – Look for statement in first few pages of journal that it is peer reviewed. Content is “reviewed” by experts in field before publication