Topic 4 DQ 1
Apr 25-27, 2022
Compare independent variables, dependent variables, and extraneous variables. Describe two ways that researchers attempt to control extraneous variables. Support your answer with peer-reviewed articles.
May 3, 2022, 6:01 PM
Experimental studies are crucial in nursing practice as they help in determining how different phenomena are interrelated in evidence-based practice. The main variables that are used in an experimental investigation are dependent and independent. On the one hand, independent variables are the variables that are changed or manipulated by the researcher to determine their relationship with a phenomenon being observed. The experimenter manipulates independent variables and observes whether there are any observable changes in the dependent variable (Titler, 2018). On the other hand, a dependent variable is what the experimenter is measuring in the experiment. A dependent variable is a phenomenon or variable being tested in an experiment (Eldawlatly and Meo, 2019). Changes in this variable are dependent on the independent variable. In an experiment, independent variables can be thought of as the cause while the dependent variable is the effect because they change depending on the alterations made in independent variables. For instance, in a study to investigate if a low-calorie diet reduces cholesterol levels in overweight patients, low-calorie intake is the independent variable while cholesterol level is the dependent variable.
Extraneous variables are any other variables in an experiment that are not under investigation and could potentially affect the internal validity of the study thus giving inaccurate research outcomes (Eldawlatly and Meo, 2019). Thus, the experimenter should always control for extraneous variables failure which could lead to inaccurate conclusions about the correlation between dependent and independent variables. In the example above, factors such as the age of the patient and other comorbid diseases could alter the results of the study if not controlled.
One of the ways that researchers control extraneous variables is through randomization. In random sampling, the researcher assigns treatments randomly to the experimental and control groups to ensure possible extraneous variables are equally distributed between the study groups, especially when the sample size is relatively large (Falkner et al., 2018). The second approach involves the use of blinding whereby, treatments are kept unknown to both the participant and the researcher.
Eldawlatly, A. and Meo, S. (2019). Writing the methods section. Saudi Journal of Anesthesia. 13(Suppl 1): S20–S22. doi: 10.4103/sja.SJA_805_18
Falkner, A. Et al. (2018). Nursing Research: Understanding Methods for Best Practice (1st Edition). Grand Canyon University Press.
Titler, M.G., (May 31, 2018) Translation Research in Practice: An Introduction. The Online Journal of Issues in Nursing, 23(2).
May 1, 2022, 6:42 PM
Please review the chart below to gain more understanding of extraneous variables.
May 1, 2022, 6:41 PM
I like the breakdown of the variables in this example.
What do you think? Do you find this helpful?
Apr 30, 2022, 7:14 PM
Dependent and independent variables are more commonly discussed than extraneous variables (Sheppard, 2020). Extraneous variables are important to consider in research, as they can ultimately affect the results of a research study. Sheppard (2020) asserts that the integrity of a research study could be compromised secondary to extraneous variables. As a researcher, completing comprehensive research, yet it lacks integrity is not desired. Furthermore, the credibility of the researcher is also diminished (Coates, 2014).
In an attempt to ensure the research is credible, the researcher should implement the necessary controls. Furthermore, maintaining the integrity of the research is also associated with making necessary controls. In research, if an outcome occurs because of an extraneous variable, it is then called a confounding variable (Sheppard, 2020). What is a way to control research to reduce extraneous variables?
Coates, H. (2014). Ensuring research integrity: The role of data management in current crises. College & Research Libraries News, 75(11), 598–601. https://doi.org/10.5860/crln.75.11.9224
Sheppard, V. (2020). Research methods for the social sciences: An introduction. Retrieved from https://pressbooks.bccampus.ca/jibcresearchmethods/chapter/4-6-extraneous-variables/
Apr 30, 2022, 7:13 PM
Your discussion of variables is informative. To enhance your understanding, please review the following example.
As a class, let us review this example to look at the differences between dependent and independent variables. I found this example to be easier to understand given its relation to healthcare.
Apr 30, 2022, 7:13 PM
Replies to Mireille Ulysse
Is there an unanswered question that remains regarding variables?
replied toWanda Felder
May 1, 2022, 6:38 PM
Replies to Wanda Felder
I believe there is unanswered questions in research variables, and these are these lead to information gaps. An example in nursing research could include pregnant mothers who start a research trial, and they represent the variable of pregnant mothers who smoke. If she and others in her variable group abandoned the trial, the data that would be collected is not going to be accurate. This can occur when there is a lack of participation in research studies. This can cause a “problem for the overall reliability and generalizability of results when recruitment goals are missed, or participants are lost to follow-up” (Brunsdon, 2019). There are a few ways to avoid this gap. One is to increase the sample size and the other is to improve retention of participants. In regard to variables, they must be considered operational variable or having “some properties such as good reliability and validity, low bias, feasibility/practicality, low cost, objectivity, clarity, and acceptance” (Kaliyadan, 2019). If these variables are low on the validity scale, there outcome of research will not be reliable leading to unanswered questions in research. Thank you, Jana
Brunsdon, D., Biesty, L., Brocklehurst, P. et al. What are the most important unanswered research questions in trial retention? A James Lind Alliance Priority Setting Partnership: the PRioRiTy II (Prioritising Retention in Randomised Trials) study. Trials 20, 593 (2019). https://doi.org/10.1186/s13063-019-3687-7
Kaliyadan, F., & Kulkarni, V. (2019). Types of Variables, Descriptive Statistics, and Sample Size. Indian dermatology online journal, 10(1), 82–86. https://doi.org/10.4103/idoj.IDOJ_468_18
Apr 27, 2022, 11:08 PM
Replies to Mireille Ulysse
When conducting research, the researcher manipulates a variable to see the outcome in another variable. The variable that the researcher can control is the independent variable. The independent variable can directly affect the result of the dependent variable. The extraneous variable is the unwanted issue of things that can skew the data in an experiment. The extraneous variable is why all studies are likely to be incorrect because every experiment has a bias (Helbig & Ambrose, 2018).
There are three categories of extraneous variables: situation, personal, and researcher-based. Situations are issues that can personally happen to the subjects in research that could not be determined before the study and are personal only to the subject or community, such as death or a natural disaster. A personal extraneous variable is an individual trait that makes every subject different such as other medical diagnoses and personal life experiences. The final and third type is the researcher-based extraneous variable. This variable is something that the researcher does that creates inconsistency from one subject, group, or community that may change collected data (Helbig & Ambrose, 2018). What makes research valuable is controlling the variable in an experiment and giving quality data and information. Researchers try their best to keep extraneous variables out of a study to provide validity and consistency to the study, but this can be close to impossible to achieve.
Keeping extraneous variables out of a study makes the study reliable and accurate. However, there is no way to make an experiment 100% free of extraneous variables because people conduct these experiments, and error is human.
However, researchers try to limit extraneous variables in experiments to include strategies such as the purification principle. The purification principle acknowledges the bias and produces a biased estimate. In addition, the purification principle recognizes the error percentage of skewed data and the percentage of data omitted in the study (Bernerth et al., 2018). Acknowledging this bias and calculating the potential of error is how researchers can control the probability of inaccurate data and skewed information from the experiment.
Bernerth, J. B., Cole, M. S., Taylor, E. C., & Walker, H. J. (2017). Control variables in leadership research: a qualitative and quantitative review. Journal of Management, 44(1), 131–160. https://doi.org/10.1177/0149206317690586
Helbig, J., & Ambrose, J. (2018). Applied statistics for health care. Gcumedia.com. https://lc.gcumedia.com/hlt362v/applied-statistics-for-health-care/v1.1/#/chapter/1
replied toTracy Tibbs-Briggs
Apr 30, 2022, 6:47 PM
Replies to Tracy Tibbs-Briggs
Thank you for your very thorough post,
Extraneous variables are fascinating, they can cause all types or disparities in an experiment because they are unexpected. Extraneous variables are almost impossible be controlled (McNiff & Petrick, 2018) but it is important to try for your research to be considered valid. An article on communications and issues with speech in children posed maturation as being a extraneous variable in their study (Rvachew &Matthews, 2017). The study researched apraxia in speech of an 8-year-old. They used a single case study which used evidence-based practice to decide when and how treatment should begin. With the study they understood the importance of using randomization to ensure the positive outcome (Rvachew & Matthews, 2017). Researchers know there may be differences between the study groups, but the thought of maturation came to them when they looked at the study as being complete and wondered if the improvement was from the intervention or the maturation (Rvachew & Matthews, 2017).
As stated by the Merriam-Webster dictionary, (2022) maturation is the process of maturing, growing up, behavioral changes and development.
This extraneous variable caused the researchers to do more testing to verify that the improvement in speech was from the intervention given. They did not leave their research to chance but ensured a trusted and valid outcome (Rvachew & Matthews, 2017).
McNiff, P. & Petrick, M., (2018). Quantitative Research: Ethics, Theory, and Research. In Grand Canyon University (Eds.), Nursing Research: Understanding Methods for Best Practice. https://lc.gcumedia.com/nrs433v/nursing-research-understanding-methods-for-best-practice/v1.1/#/chapter/3
Merriam-Webster. (n.d.). Maturation. In Merriam-Webster.com dictionary. Retrieved April 30, 2022, from https://www.merriam-webster.com/dictionary/maturation
Rvachew, S., & Matthews, T. (2017). Demonstrating treatment efficacy using the single subject randomization design: A tutorial and demonstration. Journal of Communication Disorders, 67, 1–13. https://doi-org.lopes.idm.oclc.org/10.1016/j.jcomdis.2017.04.003
replied toTracy Tibbs-Briggs
May 1, 2022, 7:05 PM
Replies to Tracy Tibbs-Briggs
To speak more of extraneous variables, Schmidt (2018) defines extraneous variables as a variable that can influence the relationship between the independent and dependent variables that can be controlled either through research design or statistical procedures. A study was conducted by Perveen et al. (2021) to evaluate stress among nursing students during initial clinical practice. In this study there were a number of extraneous variables that contributed to the student’s level of stress other than the initial clinical practice. These variables are included age of the students, housing, type of family, religion, and monthly family income. Students in this particular study that experience stress from variables other than nursing school may negatively effect the results of the survey as they may experience a higher level of stress as compared to those who do not experience stress from any other variable. One way to control extraneous variables is through randomization. Randomization prevents the selection bias and ensures against the accidental bias and it permits the use of probability theory to express the likelihood of chance as a source for the difference of end outcome (Suresh, 2011).
Schmidt, M.(2018). Measurement, statistics, and appraisal. Nursing research: understanding methods to best practice. https://lc.gcumedia.com/nrs433v/nursing-research-understanding-methods-for-best-practice/v1.1/#/chapter/4
Suresh K. (2011). An overview of randomization techniques: An unbiased assessment of outcome in clinical research. Journal of human reproductive sciences, 4(1), 8–11. https://doi.org/10.4103/0974-1208.82352
Perveen, N. ., Mondal, S. ., & Afrose, S. . (2021). Stress among nursing students during initial clinical practice in Bangladesh. OIRT journal of scientific research, 1(2), 29–35. https://doi.org/10.53944/ojsr-2107