Tag Archives: research methods

True or False: Experiment or Not

Experiments are the way that we confirm that one thing causes another.   If the study is not an experiment (or combined experiments in a meta-analysis), then the research does not show cause and effect. imagesCALQ0QK9

Experiments are one of the strongest types of research.

So…how can you tell a true experiment from other studies?   Hazel B can tell you in 4:04 and simple language at https://www.youtube.com/watch?v=x2i-MrwdTqI&index=1&list=PL7A7F67C6B94EB97E

Go for it!

[After watching video:  Note that the variable that is controlled by the researcher is call the Independent variable or Cause variable because it creates a change in something else. That something else that changes is the Dependent variable or Outcome variable.]Learning

CRITICAL THINKING:  

  1. Based on the video, can you explain why true experiments are often called randomized controlled trial (RCT)?
  2. Take a look at The Effect of the Physical and Mental Exercises During Hemodialysis on Fatigue: A Controlled Clinical Trial, that is free in full-text via PubMed. How does it meet the criteria of a true experiment as described by Hazel B in the video?

FOR MORE INFORMATION:   Go to “What’s an RCT Anyway?” (https://discoveringyourinnerscientist.wordpress.com/2015/01/23/whats-a-randomized-controlled-trial/ )

Self-Report Data: “To use or not to use. That is the question.”

[Note: The following was inspired by and benefited from Rob Hoskin’s post at http://www.sciencebrainwaves.com/the-dangers-of-self-report/]Penguins

If you want to know what someone thinks or feels, you ask them, right?

The same is true in research, but it is good to know the pros and cons of using the “self-report method” of collecting data in order to answer a research question.  Most often self-report is done in ‘paper & pencil’ or SurveyMonkey form, but it can be done by interview.

Generally self-report is easy and inexpensive, and sometimes facilitates research that might otherwise be impossible.  To answer well, respondents must be honest, have insight into themselves, and understand the questions.  Self-report is an important tool in much behavioral research.

But, using self-report to answer a research question does have its limits. People may tend to answer in ways that make themselves look good (social desirability bias), agree with whatever is presented (social acquiescence bias), or answer in either extreme terms (extreme response set bias) or always pick the non-commital middle Hypothesisnumbers.  Another problem will occur if the reliability  and validity of the self-report questionnaire is not established.  (Reliability is consistency in measurement and validity is the accuracy of measuring what it purports to measure.) Additionally, self-reports typically provide only a)ordinal level data, such as on a 1-to-5 scale, b) nominal data, such as on a yes/no scale, or c) qualitative descriptions in words without categories or numbers.  (Ordinal data=scores are in order with some numbers higher than others, and nominal data = categories. Statistical calculations are limited for both and not possible for qualitative data unless the researcher counts themes or words that recur.)

Gold_BarsAn example of a self-report measure that we regard as a gold standard for clinical and research data = 0-10 pain scale score.   An example of a self-report measure that might be useful but less preferred is a self-assessment of knowledge (e.g., How strong on a 1-5 scale is your knowledge of arterial blood gas interpretation?)  The use of it for knowledge can be okay as long as everyone understands that it is perceived level of knowledge.

Critical Thinking: What was the research question in this study? Malaria et al. (2016) Pain assessment in elderly with behavioral and psychological symptoms of dementia. Journal of Alzheimer’s Disease as posted on PubMed.gov questionat http://www.ncbi.nlm.nih.gov/pubmed/26757042 with link to full text.  How did the authors use self-report to answer their research question?  Do you see any of the above strengths & weaknesses in their use?

For more information: Be sure to check out Rob Hoskins blog: http://www.sciencebrainwaves.com/the-dangers-of-self-report/

 

 

METHODS in the Research Madness

[This is a re-post from 2014.  If you weren’t a reader then….read on…..]

fisheye booksResearch article sections are: Title, Abstract, Introduction/background,Methods, Results, Discussion, & Implications/Conclusions

METHODS =  Design, Sample, Setting, & Data collection instrument

Sometimes these above elements of METHODS are subheadings.

Sometimes not.

  • Key point #1: Design= overall plan for answering the question or proving the hypothesis.  KEYThe 2 basic types of design are 1) experimental & 2) non-experimental.   In experimental, the researcher does something to the subjects and measures the effects of that something.  In non-experimental, the research merely observes and describes what is happening without doing anything to change it.
  •  KEYKey point #2: Setting=where the study is conducted: home, hospital, office, classroom, on KEYan ocean cruise, or other.
  • Key point #3: Sample includes who/what subjects were in & excluded from the study; how many subjects were in the study; & whether subjects were selected using random methods or non-random methods.   In random selection every eligible subject has the same chance of being selected. That’s called probability sampling.  An example is drawing names from a hat.  In non-random selection only the most nearby subjects are asked to be in the study. That’s called non-probability or convenience sampling.  An example, using a clipboard to survey people who walk into a mall one day. [Note: Subjects can be people, animals, charts, hospitals, or nations.]

(Whew!….Enough for now.)

Critical Thinking Exercise:  Find the Design, Setting, & Sample in this excerpt of Methods from Mohammedkarimi et al, (2014): question

“A double-blind, randomized clinical trial (RCT) was performed among 90 adult patients with acute headache in Shahid Rahnemoon Emergency Center of Yazd city of Iran (45 patients in lidocaine group and 45 patients in placebo group). Patients with history of epilepsy, allergy to lidocaine, signs of skull base fracture, Glasgow Coma Scale (GCS) < 15, patients younger than 14 years and patients who had received any medication in previous 2 h were excluded.”

“Who’s in?” Sampling Made Simple

So many great resources are out there at your fingertips.   In the next few blogs, I’ll point you to some of them.Heart Books

If you have not yet discovered the hidden jewel of the tab, “Research Made Simple,” on the Evidence-Based Nursing website at http://ebn.bmj.com/ , you should check out its full text pdf articles. An especially nice resource if you are in graduate school or maybe even a BSN course on research.

Here is a sample of one from June 9, 2014 of the population of articles at EBN.

ball sample“Sample selection is a key factor in research design and can determine whether research questions will be answered. …It is critical to take the time to clearly identify the population of interest for the specific research question. Nursing researchers are usually interested in answering questions about very specific patient populations which can span an incredible array of possibilities applying to international, national, local and organisational contexts. Research populations closely reflect nursing specialties, some of which are gender (eg, pregnant women) and age specific (eg, adolescent diabetes). It is rarely feasible to conduct a study that reaches every patient in the population of interest, therefore a subset or sample of that population is selected for study.” (para 1-2 Retrieved from http://ebn.bmj.com/content/17/2/32.short?g=w_ebn_research_tab ) [note: I added the bold]

I invite you to use the comments section to post URLs for other great sites!

Critical Thinking: Read the previous blog on representatives & then QUESTIONdecide for yourself whether this single EBN article on sampling is representative of clear & simple explanations. Samples can be things, not just people. What questions should you ask me about my sampling procedure?

For More: Check out tab “Research Made Simple,” on the Evidence-Based Nursing website at http://ebn.bmj.com/ .   OR try this <5 minute simple sampling youtube video  https://www.youtube.com/watch?v=Gs-gLeYuDZw