Part 4: EBP Searching and Critical Appraisal of Evidence-based Literature

Part 4: EBP Searching and Critical Appraisal of Evidence-based Literature

Welcome to part four of our discussion
of searching and critical appraisal of evidence-based literature. Let’s look at
a variety of articles to see what types of things you want to look for when
appraising them. So here we have a quantitative study, a randomized control
trial called “Maintaining patency with packed red blood cell infusions” and
here’s some questions we’re going to look at– Is this a significant topic? Is
the hypothesis clearly stated and focused? Who are the authors of the
article? Is it peer-reviewed? Does the study design fit the research question? Who are
the participants? Were they randomized? Were they blinded? How were the outcomes
measured? Were there limitations that were spelled out? Let’s take a look at
this article. Here’s our study– “Maintaining patency with packed red
blood cell infusions comparison of IV normal saline infusion and normal saline
syringe method.” Let’s scroll down and take a look at some of the aspects of
the study. You can see there’s a literature review spelling out what
databases were reviewed and what years and other limits were placed on that
search. You can see that the authors of the study are spelled out,
many of them are nurses or PhDs, giving authority to the authors. If we
continue on we can see the objective of the study the purpose and hypothesis is
spelled out for this study. They’re showing you the design and sample size
which is right up front, and that the study was reviewed by an institutional
review board. Methodology for the study is explained and the randomization of
the subjects is explained as well. You can see they’ve published the data
collection tool, which is great because perhaps it can be duplicated in another
study by another researcher. And, then they lay out some results here showing
they find no statistical difference between the two methods and tell you who
completed the data and then give you information in the discussion about the
study limitations that might have occurred and the need for future
research. So all in all this is a pretty well laid out study. The references are
current to the time period of the study and all spelled out. Next
we’re going to look at a qualitative example, “Making sure:
Registered nurses watching over their patients,” in the journal, Nursing Research.
Some questions we would ask in a qualitative study is there a clear
goal and why is the study important? How were the participants recruited and was
there a relationship between the researcher and participants? Is the
research methodology appropriate? What data collection tool was used were there
ethical issues? Was the data analysis rigorous? Could you read a clear
statement of the findings? Is this research valuable and does it add to our
understanding of this topic? Could you transfer this research to your own
setting? Let’s take a look at this article–here we are in our article in
nursing research first we can see that there is a structured abstract
with the background, objective, methodology, results and conclusions all
laid out right at the beginning with the author supplied keywords. Oftentimes
when you see a structured abstract you can
look at that abstract before getting to the body of the article and
see if a lot of the criteria you’re looking for are met in that abstract. If
you feel you need to go further, you can look at the rest of the sections of the
article. We see here that Dr. Schmidt is a nurse and a professor at Loyola
University giving credibility to the author. The study research question is
laid out, as noted as generating a substantive theoretical model of the
process used by registered nurse nurses as they watch over their assigned
patients during a single work shift. It is stated here they use a classical
Grounded Theory method and the IRB for the institution approved this study. They’re telling you where their participants were recruited from. Now in
this study the participants were recruited through professional
relationships between the investigator and the hospital officials and the data
was collected in a semi structured interview style by person or by
telephone. Also, the data was collected in interviews done by the PI and graduate
students. The sample size, you’ll notice is 15, that’s a relatively small
sample size, usually you want to have larger sample sizes to give validity to
the study. You can see the data collection and analysis and how long the
interviews were held and that they were audiotaped. They
categorized different points or things that were said by the interviewee so
something like “knowing what’s going on” was collected, “being close,” “making sure”
–these are terms that would have been stated or concepts stated
in the interview process and probably coded by the investigator. Those are
spelled out throughout with explanations and more information. In the discussion they talk about the limitations that the study included and then you can
see that they denoted that further study of the theory needs to be
conducted. Their references are listed here. Some of their references
are older and could be that they’re seminal to the points that were made in the
paper. The study was given some funding by an award. So that’s our
qualitative study. Let’s move on to our next study. Our next example here is a
systematic review and as you may remember through our earlier discussion, a
systematic review is considered one of the highest level of evidence for a
research article. This review is from the Cochrane Database of Systematic
Reviews. Questions you might ask in a systematic review —is the research
question well focused? Is the literature search thorough? Does the study include
important rigorous studies, such as randomized control trials? Are the
outcome measures expected? Is this a reproducible review? How did they report
the results and can you transfer this to your local population? Let’s take a
brief look at this study. Here’s our Cochrane systematic review on “Short
course antibiotics for acute otitis media” One thing about the Cochrane
systematic reviews is that they’re nicely laid out with a table of contents. There is a structured abstract, so you
can look at the different sections of that abstract and pull out information
from there. From the objective to the search methodology and databases used. They include the
selection criteria for the participants and how they analyze the data. It will
even list out the main results of the study you can see in this case 49 trials
were looked at that had over 12,000 participants, so that’s a very high
sample size and lending a lot of credibility to the results. There’s
always a plain language summary in these Cochrane reviews and additional data
that you can see here oftentimes laid out in a table. If you look further into
the study after you’ve looked at the preliminary information, you can go
deeper into that information by looking deeper into the methodology used and the
literature review and how that literature review was conducted– what
terminology they used. They may use different databases then we have
available, but you can apply a lot of the same information to the databases we
have here at Regis. Some of these
reviews can be rather long, this one is over 70 pages so you may want to
consider that if you want to print it. You might just want to download it to
your computer. They’re very detailed and give you a lot of great information.
You can always go to the Cochrane Library and pull up reviews by browsing
on different subjects or enter a few terms and look look for reviews on your
topic. That includes our four part series on searching and critical
appraisal of evidence-based literature. I thank you for listening in and remember
the Regis Library if you need help. Always look for your librarian to help you out
anytime you need assitance, don’t hesitate to call or email me Kim O’Neill or stop by
the Research Help Desk and see any one of our great librarians here at the
library. Thank You!

local_offerevent_note October 11, 2019

account_box Matthew Anderson


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