Category Archives: reading research

“Should you? Can you?”

ApplesOranges2Quasi-experiments are a lot of work, yet don’t have the same scientific power to show cause and effect, as do randomized controlled trials (RCTs).   An RCT would provide better support for any hypothesis that X causes Y.   [As a quick review of what quasi-experimental versus RCT studies are, see “Of Mice & Cheese” and/or “Out of Control (Groups).”]

So why do quasi-experimental studies at all?  Why not always do RCTs when we are testing cause and effect?  Here are 3 reasons:

#1  Sometimes ETHICALLY the researcher canNOT randomly assign subjects to a control Smokingand an experimental group.  If the researcher wants to compare health outcomes of smokers with non-smokers, the researcher cannot assign some people to smoke and others not to smoke!  Why?  Because we already know that smoking has significant harmful effects. (Of course, in a dictatorship, by using the police a researcher could assign them to smoke or not smoke, but I don’t think we wanna go there.)

#2 Sometimes PHYSICALLY the researcher canNOT randomly assign subjects to control & Country of Originexperimental groups.   If the researcher wants to compare health outcomes of
individuals from different countries, it is physically impossible to assign country of origin.

#3 Sometimes FINANCIALLY the researcher canNOT afford to assign subjects randomly PiggyBankto control & experimental groups.   It costs $ & time to get a list of subjects and then assign them to control & experimental groups using random numbers table or drawing names from a hat.

Thus, researchers sometimes are left with little alternative, but to do a quasi-experiment as the next best thing to an RCT, then discuss its limitations in research reports.

Critical Thinking: You read a research study in which a researcher recruits the 1st 100 patients on a surgical ward January-March quarter as a control group.  Then the researcher recruits the 2nd 100 patients on that same surgical ward April-June for the experimental group.  With the experimental group, the staff uses a new, standardized pain script for better pain communications.  Then the pain communication outcomes of each group are compared statistically.

  • Is this a quasi-experiment or a randomized controlled trial (RCT)?
  • What factors (variables) might be the same among control & experimental groups in this study?
  • What factors (variables) might be different between control & experimental groups that might affect study outcomes?
  • How could you design an ethical & possible RCT that would overcome the problems with this study?
  • Why might you choose to do the study the same way that this researcher did?

For more info: see “Of Mice & Cheese” and/or “Out of Control (Groups).”

OUT OF CONTROL (groups)! The weak link in the cause-&-effect chain

Welcome back after a bit of silence on my end!welcome[1]

In the last “Quasi-wha??” blogpost, I described 1 type of experimental design: Quasi-experimental.  To review… In quasi-experimental designs, the researcher manipulates some variable, but either 1) doesn’t randomly assign subjects to a control and experimental group OR 2) doesn’t have a control group at all.

For example, the researcher may introduce pet therapy on unit #1 and avoid pet therapy on unit #2 and then afterwards compare the anxiety levels of patients on the 2 units.  That study has a control group (unit #2), but because patients weren’t (& probably couldn’t be) randomly assigned to the units, this would be a quasi-experimental study. The control group in this pet therapy case is what researchers call a “non-equivalent control group.”   Non-equivalent means the groups are different in ways that might affect study results! [Note: For review of what constitutes a true experimental study see first part of  “Quasi-wha??” blogpost.]

WeaknessHerein lies a weak link in the cause-and-effect chain. Quasi- designs are NOT as strong as true experimental designs because something other than our treatment (in this case pet therapy) may have created any difference in outcomes (e.g., anxiety levels).  Why?   Here’s your answer.

ApplesOranges
Unit #1

In an experimental study, randomly assigning subjects to a

ApplesOranges
Unit #2

control and a separate experimental group means that all the little, variable weirdities of all subjects are equally distributed to each group.  Each group is the same mix of different types of people. This means we can assume that both groups are the exact same type of
people in regard to things that may influence study outcomes, such as attitudes, values, preferences, beliefs, anxiety level, psychology, physiology and so on.

ApplesOranges2
Unit #1=Apples.        Unit #2=Oranges

In contrast, in the quasi-experimental pet therapy example above, there is probably something that caused a certain type of person to be on unit #1 and a different type to be on unit #2.  Maybe it was their diagnosis, their doctor, their type of surgery, or other.  Thus, we cannot assume that people in unit #1 and unit #2 groups are the same before pet therapy, and so any differences between them after pet therapy might have already existed.

So why do quasi-experimental studies at all?? There are great reasons!  Stay tuned for next blogpost.

Critical thinking: Check out free full-text, quasi-experiment Gough et al., (2017). Tweet for Behavior Change: Using Social Media for the Dissemination of Public Health Messages.  

  1. What makes this a quasi-experimental design?  [Hint: Does it have a control group? Were subjects randomly assigned to groups?  Are both randomization & control group missing?]
  2. What might have caused the change in behavior, instead of the tweets? 
  3. What contribution do you think the study makes to improving practice?

For more information on studies with non-randomized control groups see “Of Mice & Cheese”  or comment below.  Let’s talk!

Quasi- wha??

Two basic kinds of research design exist:  

  1. Experimental design in which
    • the researcher manipulates some variable,randomized
    • the participants are randomly assigned to groups, &
    • one group is a control group that gets a placebo or some inert treatment so that outcomes in that group can be compared to the group(s) that did get the treatment.
  2. Non-experimental design in which the researcher doesn’t manipulate anything, but just observes & records what is going on.   Some of these are descriptive, correlational, case, or cohort study designs for example.

One particularly interesting “experimental” design is one in which 1 or 2 of the experimental design ideal requirements as listed above are missing.  These are called quasi-experimental designs.

thinking3In a quasi experimental design

  • The researcher manipulates some variable, but….
  • Either the participants are NOT randomly assigned to groups
  • &/OR there is no control group.

A quasi-experimental design is not as strong as a true experiment in showing that the manipulated variable X causes changes in the outcome variable Y.  For example, a true experimental study with manipulation, randomization, and a control group would create much stronger evidence that hospital therapy dogs really reduced patient pain and anxiety.  We would not be as confident in the results of a quasi-experimental design examining the exact same thing.  In the next blog, we’ll examine why.

For more info:  Check out earlier blog:    “What is an RCT anyway?” at https://discoveringyourinnerscientist.com/2015/01/23/whats-a-randomized-controlled-trial/Idea2

Critical thinking:  Go to PubMed & use search terms “experiment AND nurse” (without the quotation marks).  Open an interesting abstract and look for the 3 elements of a classic experimental design. Now look for “quasi experiment AND nurse” (without the quotation marks.)  See what element is missing!

“Here Comes Santa Claus?” What IS the Evidence?

How strong is the evidence regarding our holiday Santa Claus (SC) practices? And what are the opportunities on this SC topic for new descriptive, correlation, or experimental research?  Although existing evidence generally supports SC, in the end we may conclude, “the most real things in the world are those that neither children nor men can see” (Church, as cited in Newseum, n.d.).santa3

If you want to know the answers, check out: Highfield, M.E.F. (2011).  Here comes Santa Claus: What’s the evidence? Advanced Emergency Nursing Journal, 33(4), 354-6. doi: http://dx.doi.org.libproxy.csun.edu/10.1097/TME.0b013e318234ead3   Using bona fide published work, the article shows you how to evaluate the strength of evidence and how to apply it to practice.   You can request a full-text for your personal use from your library or from the author via www.researchgate.net/home .  

Critical thinking: Check out this related research study with fulltext available through PubMed: Black Pete through the eyes of Dutch children
(https://www.ncbi.nlm.nih.gov/pubmed/27322583 ).   Write a follow-up research question based on the findings of this study & post in comments below.

For more info: For those unfamiliar with ResearchGate, it is a site where you can track authors who publish in your area of interest, and you can set up your own profile so that people can track your work.  Take a look.   

DATA COLLECTION SECTION! (Methods in the Madness)

Key point! The data collection section of a research article includes: who collects what data when, where & how.

In previous blogs we’ve looked at title, introduction, and other elements of methods section (design, sample, & setting). In this one let’s take a look at data collection.

Data are a collection of measurements. For example, student scores on a classroom test might be 97, 90, 88, 85, & so on. Each single score is a datum; collectively they are data.

What data are collected is answered in this section. The data (or measurements) can be counting-hashmarksnumbers OR words. For example, numbers data might include patient ratings of their pain on a 0-10 scale. An example of word data would asking participants to describe something in words without counting the words or anything else.  For example, word data might include patient descriptions pain in words, like word-art“stabbing,”  “achy,” and so on.  Sometimes a researcher collects both number and word data in the same study to give a more complete description.  You can see how knowing the patient’s pain rating and hearing a description would give you a much clearer picture of pain.

  • Studies reporting data in numbers are called quantitative studies
  • Studies reporting data in words/descriptions are called qualitative studies
  • Studies reporting number & word data are called mixed methods studies

How the data are collected includes what instrument or tool was used to gather data (e.g., observation, biophysical measure, or self-report) and how consistently & accurately that tool measures what it is supposed to measure (e.g., reliability & validity). Also included is who collected the data and the procedures that they followed—how did they obtain consent, interaction with subjects, timing of data collection and so on.

Now you know!

Critical thinking question: Did these authors use qualitative or quantitative data collection methods?  Coelho, A., Parola, V., Escobar-Bravo, M., & Apostolo, J. (2016). Comfort experience in palliative care, BMD Palliative care, 15(71). doi: 10.1186/s12904-016-0145-0.  Explain your answer.

Strong nursing leadership is essential to evidence-based practice

priority“The Institute of Medicine (IOM) set a goal that, by 2020, the majority of healthcare practices and decisions would be evidence-based.Yet…only three percent of the executive-level nurse leaders surveyed ranked EBNP as a top priority at their own organizations. What’s worse, more than half said EBNP is practiced at their organizations only “somewhat” or “not at all.”  Posted on July 19, 2016HTimothy  at American Sentinel.   

For full text see the source link: http://www.americansentinel.edu/blog/2016/07/19/strong-nursing-leadership-is-essential-to-evidence-based-practice/

Critical Thinking: Given all the demands of the healthcare questionenvironment, how can we make this goal happen.   

Google’s Beauty is Only Skin Deep: Go for the Database!

maxresdefaultGoogle–not to mention yahoo, bing & other web search engines–are mere popularity contests of literature.   Google Scholar is a step up, but it is still a search engine.  It can miss important articles entirely.

If you want to be sure that you are getting the BEST, you gotta look in the right place if you want to find the right articles on the right topic at the right time!Beauty contest winner

You need a Database!

Don’t believe me?  Watch “What are databases and why you need them?”(youtube 2:34)

Reputable publishers give away very few articles for free, so when you want the best literature out there you need a Database that will systematically help you to find quality articles that fit your topic.

PubMed.gov is a tax funded database that is highly comprehensive.  CINAHL is strong on nursing literature.  If you are enrolled in a university, you have access to lots of full-text articles at no added cost.  Check with your librarian if your database search is not turning up what you need–with a few hints, you could get the best.

Needle in haystackFor more info:  Look for that needle in the haystack.