Respond to the Main post bellow, in one or more of the following ways: Ask a probing question, substantiated with additional background information, and evidence. Share an insight from having read your colleagues’ postings, synthesizing the information to provide new perspectives. Offer and support an alternative perspective using readings from  the classroom or from your own review of the literature in the Walden  Library. Validate an idea with your own experience and additional sources. Make a suggestion based on additional evidence drawn from readings or after synthesizing multiple postings. Expand on your colleagues’ postings by providing additional insights or contrasting perspectives based on readings and evidence.                                   INITIAL POST  An Intervention Program to Promote Health-Related Physical Fitness in Nurses              This quantitative, quasi-experimental study conducted by Yaun et al.  (2009) aimed to determine the effects of an exercise intervention on  nurses’ health-related physical fitness. The researchers also expressed  an explicit interest in the relationship between physical fitness and  the incidence of musculoskeletal disorders. Taiwanese nurses from five  different units volunteered to be part of the study. The participants  were divided into two groups with 45 nurses in the experimental group  and 45 nurses in the control group. There was no randomization, but all  the participants gave written informed consent (Yaun et al., 2009).  Internal Validity               According to Polit and Beck (2017), internal validity pertains to the  empirical relationship between the independent variable and the final  results. Researchers must establish that the intended cause created the  effect, and that it was not influenced by other variables (Polit &  Beck, 2017). After all, correlation does not equal causation, and an  astute researcher will adeptly identify and control convoluting  variables. Further, Andrade (2018) asserts that internal validity  assesses whether the design of the study, the conduct of the  researchers, and the analysis of the results answer the research  question without bias (Andrade, 2018).  Consequently,  the research conducted by Yaun et al. did have some issues that  negatively impacted the internal validity of their research. Firstly,  convoluting variables were not adequately controlled. The exclusion  criteria consisted of cardiovascular disease, diabetes, hypertension,  renal disease, pulmonary disease, severe musculoskeletal aches, and  pregnancy. However, other significant variables such as age, gender,  marital status, educational level, or other medical issues. It is worth  noting that the diet and exercise habits of the participants were not  limited by the researchers. Moreover,  the nurses in the experimental group worked a fixed schedule whereas  nurses in the control group worked alternating shifts. Secondly, the  lack of randomization coupled w ...

1. Respond to the Main post bellow, in one or more of the
following ways:
Ask a probing question, substantiated with additional
background information, and evidence.
Share an insight from having read your colleagues’ postings,
synthesizing the information to provide new perspectives.
Offer and support an alternative perspective using readings
from the classroom or from your own review of the literature in
the Walden Library.
Validate an idea with your own experience and additional
sources.
Make a suggestion based on additional evidence drawn from
readings or after synthesizing multiple postings.
Expand on your colleagues’ postings by providing additional
insights or contrasting perspectives based on readings and
evidence.
INITIAL POST
An Intervention Program to Promote Health-Related Physical

2. Fitness in Nurses
This quantitative, quasi-experimental study conducted
by Yaun et al. (2009) aimed to determine the effects of an
exercise intervention on nurses’ health-related physical fitness.
The researchers also expressed an explicit interest in the
relationship between physical fitness and the incidence of
musculoskeletal disorders. Taiwanese nurses from five
different units volunteered to be part of the study. The
participants were divided into two groups with 45 nurses in the
experimental group and 45 nurses in the control group. There
was no randomization, but all the participants gave written
informed consent (Yaun et al., 2009).
Internal Validity
According to Polit and Beck (2017), internal validity
pertains to the empirical relationship between the independent
variable and the final results. Researchers must establish that
the intended cause created the effect, and that it was not
influenced by other variables (Polit & Beck, 2017). After all,
correlation does not equal causation, and an astute researcher
will adeptly identify and control convoluting variables.
Further, Andrade (2018) asserts that internal validity assesses
whether the design of the study, the conduct of the researchers,
and the analysis of the results answer the research question
without bias (Andrade, 2018).
Consequently, the research conducted by Yaun et al. did have
some issues that negatively impacted the internal validity of
their research. Firstly, convoluting variables were not
adequately controlled. The exclusion criteria consisted of
cardiovascular disease, diabetes, hypertension, renal disease,
pulmonary disease, severe musculoskeletal aches, and
pregnancy. However, other significant variables such as age,
gender, marital status, educational level, or other medical

3. issues. It is worth noting that the diet and exercise habits of the
participants were not limited by the researchers.
Moreover, the nurses in the experimental group worked a fixed
schedule whereas nurses in the control group worked
alternating shifts. Secondly, the lack of randomization coupled
with the fact that the participants worked for the same
organization could have contaminated the results. Thirdly,
while the results of the research showed the exercise
intervention improved the physical fitness of the participants in
the experimental group, participants were not evaluated for
musculoskeletal improvements.
Recommendations to Strengthen Internal Validity
A different research design would have strengthened internal
validity. Randomization is the most effective way to control
individual characteristics of participants. Randomization also
eliminates for the Hawthorne Effect, which occurs when
participants behave differently because they know they are
being studied. Moreover, a cross-over design is highly effective
when groups are being compared to one another. Although, this
design is subject to carryover bias, in which an effect carries
over from one experimental condition to another (Polit & Beck,
2017).
I contend that a randomized control trial with a cross over
design would have increased the strength of the internal
validity in this study. In a cross-over design participants serve
as their own control group, which would negate the convoluting
variables that influenced the results of this study, and would
more accurately gauge changes resulting from the exercise
intervention. I would also add a metric to assess the
musculoskeletal status of the participants. To limit the effects
of carryover bias, the health metrics of the participants would
be obtained before the exercise intervention to establish a

4. baseline, then after the exercise intervention, and finally, after
a wash-out period, the metrics should be re-recorded.
The Impact of Changes on Other types of Validity
In contrast to internal validity, statistical validity is not
concerned with the causal relationship between variables, but
rather measures the mathematical correlation of all
relationships that occur between the variables (Polit & Beck,
2017). The randomized control, crossover design would
improve statistical validity because the participants would
serve as their own control group making statistical analysis
more powerful. Construct validity determines if the outcome
measured corresponds to the theoretical construct of the study
(Polit & Beck, 2017). In this research, the theoretical construct
was Pender’s health promotion model. Construct validity also
would have been improved by changing the design of the study.
The same health promotion strategy yields different outcomes
for different participants based on individual differences. The
modification of the study’s design would have negated these
individual differences. External validity indicates if the results
of the research will remain the same when applied to other
people or settings (Polit & Beck, 2017). Again, a change in the
design of this research would optimize external validity which
would increase the likelihood of the results influencing
evidence-based practice.
Failure to Consider Validity in Research
Failing to properly account for and control variables threatens
the validity of the results yielded from the research. The rigor
of the research design may be the most important factor in
strengthening or weakening validity, as evidenced by the
hierarchy of research studies in the evidentiary pyramid. Other
elements such as biased statistical analysis, unreliable
implementation of an intervention, carryover bias, and the

5. Hawthorne Effect are just a few variables that can threaten the
validity of a research study (Polit & Beck, 2017). Since
research guides evidence-based practice, failure to ensure the
validity of results directly affects patient outcomes;
unfortunately, the effects of poorly executed research impacts
all research. People are inherently inclined to remember
negative consequences over positive outcomes. Improper
research regarding vaccines has created an anti-vaccination
movement that is highly problematic. Big tobacco companies
produced improper research that may have resulted in people
continuing to smoke longer than they otherwise would have.
The failure to appropriately consider validity in research is a
grave mistake that should be avoided at all costs.
References
Andrade, C. (2018). Internal, external, and ecological validity
in research design, conduct, and evaluation.
Indian Journal of Psychological Medicine,40
(5), 498. doi:10.4103/ijpsym.ijpsym_334_18
Polit, D. F., & Beck, C. T. (2017).
Nursing research generating and assessing evidence for nursing
practice
. Philadelphia: Wolters Kluwer.
Yuan, S., Chou, M., Hwu, L., Chang, Y., Hsu, W., & Kuo, H.
(2009). An intervention program to promote health-related
physical fitness in nurses.
Journal of Clinical Nursing,18
(10), 1404-1411. doi:10.1111/j.1365-2702.2008.02699.x