Brown: Chapter 13 Flashcards
EBP involves….
locating, reading, evaluating, and interpreting the best unbiased studies to answer a clinical question
What is a systematic review?
It uses a scientific approach to answer a research question by synthesizing existing research rather than collecting new data
Considered secondary research, conducted after a body of research has developed around a topic and by authors who are not the primary authors of the primary research studies.
Can be used to assimilate the research for any type of research, including assessment tools, intervention approaches, descriptive and predictive studies, and qualitative research.
What is a narrative review?
Before EBP was widely adopted, it was common for researcher to publish narrative reviews that summarized the literature and, in some cases, included clinical recommendations.
The “system” of conducting the review, mirrors the steps of primary research:
A research question is written.
The methodology is defined.
Data are collected.
Results are analyzed.
Your critically appraised paper communicates the evidence described in your study as ___.
primary research
How are finding reported for systematic reviews?
Findings are reported via Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA).
How do we find systematic reviews?
Conducting a search of PubMed or CINAHL using the limitation of “systematic review” constrains the search to relevant articles.
PEDro, OTseeker, and the Evidence Map from the American Speech-Language-Hearing Association (ASHA) provide searchable databases specific to the physical therapy, occupational therapy, and speech-language pathology disciplines, respectively.
The Cochrane Collaboration is a key source of systematic reviews in all areas of medical practice.
What is Cochrane Collaboration?
- The organization conducts rigorous, high-quality reviews available to the public free of charge (and regularly updated).
- Reviews must follow published guidelines for performing the review (e.g., PRISMA).
- Cochrane reviews typically limit inclusion of studies to RCTs.
List and describe the sections of a systematic review.
- The abstract provides a summary of the review.
- The introduction presents background information on the topic, the need for the review, and a purpose statement or research question.
- The methods section differs from individual studies because the data collected are gleaned from other studies, not from individuals/clients.
- The results section gives which studies met the criteria and synthesizes the information to explain what the evidence as a whole shows with regard to a research question.
- The discussion section summarizes the results and provides clinical recommendations; the limitations of the review are also acknowledged.
When evaluating systematic reviews, what should you take into account?
their replication, publication bias, and heterogeneity
What is replication of a systematic review?
Replication is the same or similar study conducted more than once because multiple studies enhance confidence in the findings by providing evidence from several perspectives.
- But, as a source of evidence, a systematic review is only as strong as the studies it contains.
What is the publication bias of a systematic review?
Publication bias suggests that researchers are more likely to submit research and journals are more likely to publish it when the findings are positive.
- Limiting a systematic review to published studies will likely mean that the findings will be skewed toward the positive.
- Finding unpublished research could necessitate contacting researchers who are known to do work concerning the topic of interest or conducting searches of grey literature.
- Registration of clinical trials via ClinicalTrials.gov reduces the effect of publication bias on the outcomes of systematic reviews.
What is study heterogeneity of a systematic review?
Study heterogeneity refers to differences in samples, interventions, settings, outcome measures, or statistical analyses among studies.
- Systematic reviews may address study heterogeneity with strict inclusion criteria that only allow very similar studies, but this can detrimentally limit the number of studies to include.
- Another approach is to provide subanalyses of the results that describe findings within different conditions.
Systematic reviews may use a quality assessment such as the ____ to evaluate the quality of each individual study.
PEDro scale
Combining the findings of multiple studies to provide a result that reflects the combination of the results
Meta-analysis
Qualitative results are also combined in systematic reviews through a process of
thematic synthesis
True or false: All meta-analyses are systematic reviews, but not all systematic reviews are meta-analyses.
True, meta-analysis is a type of systematic review that uses the same theoretical constructs and measures.
What is a limitation of the narrative review format?
The reader must have a great deal of confidence in the author, trusting that the author has done a thorough and unbiased report on the subject.)
As a source of evidence, what type of study should a systematic review of efficacy studies include to offer Level I evidence?
RCT
Why are different outcome measures or statistical analyses among studies problematic for a systematic review?
Because differences in the reliability and validity of measures can affect the results.
What is grey literature?
Print and electronic works that are not published commercially or are difficult to find
How does a meta-analysis increase statistical power?
By increasing the number of participants when compared with a single study so can it potentially detect smaller differences among groups
The first step in a meta-analysis involves
calculating an effect size for each individual study
In a meta-analysis, ____ may be more relevant than statistical significance, because they measure the impact of the intervention or condition on the client
effect sizes
What is the second step of a meta-analysis?
to pool the effect size from all of the studies to generate an overall effect
Why can a pooled effect size provide a more accurate representation of the impact of a study?
It takes into account multiple studies
Meta-analyses typically include a ___ statistic that assesses the amount of statistical heterogeneity across the studies; too much heterogeneity may be reason to avoid combining the results in a meta-analysis.
“non-combinability”
What does a random effects model calculate?
calculates effect sizes when known study heterogeneity exists
Some of the most common in health-care research include:
Standardized Mean Difference or Cohen’s d for continuous variables
Odds ratios or hazards ratios for difference studies with dichotomous variables
r values and r2 values for studies that use correlations to examine the strength of the relationship between variables or predictive studies
The results of a meta-analysis are often displayed as a ___.
forest plot
What is a forest plot?
It graphs the effect size of each individual study against a reference point and allows you to visualize the pattern of results from the meta-analysis.
The vertical line indicates the point at which there is no effect: for intervention studies comparing an experimental with a control group, 0 indicates no effect; for odds ratios, hazard ratios, and risk ratios, 1.0 indicates no effect.
The effect of each study is plotted with a square, with studies having greater weight represented with a larger square; the horizontal lines off the square indicate confidence intervals.
The overall effect with all studies pooled is indicated at the bottom with a diamond, its width indicating the confidence interval for the pooled effect.
What is a scoping review?
A scoping review provides an overview of the existing literature and often clarifies key concepts on a topic, but it does not answer a specific question, is not intended to provide a detailed synthesis of the literature, nor does it include a critical appraisal of the literature, but it can provide the basis for determining if a systematic review is possible.
What does a strong synthesis of qualitative research do?
A strong synthesis of qualitative research does more than merge the findings of several studies; rather, it finds novel interpretations in the synthesis of the data.
Clinical practice guidelines provide…
recommendations for practitioners to address specific clinical situations
The best practice guidelines include…
The best practice guidelines include the highest level of evidence available on the topic, which is then combined with expert opinion, and in some cases the client’s perspective, to help translate research to practice.
Why is the time frame of the research an important consideration in evaluating a practice guideline?
Practice changes quickly, so practice guidelines can quickly become outdated. In addition, because it takes a long time to develop a good practice guideline, the evidence used to develop the guidelines may become outdated.
When evaluating practice guidelines…
Consider the reputation and resources of the organization that created it; ensure the author has no conflicts of interest.
Evaluate the timeliness of the research and the specific population and setting for which the guideline is developed.
They should be transparent about the process used to review and evaluate the evidence; the best follow the process of a systematic review.
They should undergo a rigorous review process that involves multiple components and many individuals.
Each recommendation should give information that is helpful in determining whether it should be adopted, including the associated level of evidence, its potential impact, and its applicability and generalizability.
What is the Appraisal of Guidelines for Research and Evaluation (AGREE) Instrument II?
It examines the scientific rigor of the guidelines, involvement of relevant stakeholders, and transparency and clarity in the report.
