Public Health Module Assignment: Incidence, Prevalence, RCTs Analysis

This assignment addresses key concepts in public health, including the use of incidence and prevalence data in advising policy makers on childhood obesity and managing a coronavirus outbreak. It then explores the limitations of randomized controlled trials (RCTs), providing a public health example where their use is inappropriate. The assignment further analyzes a specific RCT from the TUA library, discussing its benefits, limitations, and alternative study designs. It also includes critical appraisal of an observational study using the CASP tool, and discusses the barriers and facilitators to effective disease surveillance. Finally, it differentiates between systematic reviews and critical appraisals, highlighting their similarities and differences in summarizing evidence. The student provides detailed answers to each question and includes relevant references.

PART A
Module 1: Discussion Topic 1:
Incidence and Prevalence
Imagine that you are providing advice to a State Minister for Health on a new policy to
mitigate childhood obesity. Would you use incidence or prevalence data to support your
policy and why? Now imagine that you are providing advice on how Australia should
manage an outbreak of Coronavirus. Would you present him/her with incidence or prevalence
data to support your policy and why?
In the case of childhood obesity, I would use prevalence data because the data includes both
old and new cases and the aim to reduce childhood obesity can be best measured using
prevalence data. In the second case, when advising on an outbreak of Coronavirus, incidence
data is best used because coronavirus is a new contagious disease and the policy would seek
to reduce spread by knowing how many new cases emerge over a certain period of time
(Ward, 2013). The focus of the second case is a disease outbreak that is best informed by
incidence data. In the case of coronavirus, efforts to understand the disease better in reference
to its causes and prevention strategies are obtained by studying the characteristics of the new
cases. Unlike coronavirus, the policy on childhood obesity is directed at acting on what is
already known; thus, working with prevalence data is more acceptable in this former
situation.
Module 2: Discussion Topic 2:
Randomised Controlled Trials When would the use of a randomised controlled trial be
inappropriate? Give a public health example and outline the reasons for your conclusion why
randomised control trial would not be appropriate in this context.
Randomized controlled trials entail manipulation of an intervention; hence, it is no
appropriate when determining he efficacy of health promotion programs due to a violation of

ethical concepts (Rosen, Manor, Engelhard, & Zucker, 2006). A health promotion program
like screening would not be compared to lack of screening as it would violate the ethical
principles of justice and beneficence. Health promotion activities are usually employed on
healthy people, and if a researcher aims to determine the effect of a health promotion
program, he or she would need to adopt a clinical approach. Otherwise, there is no way that a
proportion of the general population would be exposed to an intervention and a different
proportion would not be exposed to any intervention. Again, it is difficult to attain external
validity in randomized controlled trials, and in the case of a population-based approach,
obtaining a homogenous population is a challenge and thwarts generalizability of findings.
Module 3: Discussion Topic 1:
Controlled Trials Use the TUA library to find an article describing a randomised control trial
in an area of public health that you find interesting and summarise it briefly. What are the
benefits and limitations of using an RCT in this specific context (and I'm interested in your
opinions, not just the statements from the researchers!)? Could any other study designs have
been used to explore the same research question?
In an attempt to determine the efficacy of a novel program in managing overweight and
obesity in pre-schoolers, the randomized controlled trial was used. A quasi- experimental
study using a pre-post-test approach would have been used but it would not have yielded the
same results. The randomized controlled is a more accurate approach in determining the
effect of the new program (Ek et al. 2019). Due to the fact that the randomized controlled
trial is bound by ethical principles it is not possible to determine the absolute effect of an
intervention without a comparator. Otherwise, in the current randomized controlled trial, the
authors have addressed all the gaps that could jeopardize the quality of the results. Also, the
standard care in the current study is not defined; hence, what is termed as standard care might

not be standard care. Adequacy of the sample population is no ascertained due to a lack of
statistical power use or procedure of ample size determination.
PARTB
Discussion (Module 4):
Discussion Topic 1 Search the literature for an observational study for critical appraisal.
Choose an appropriate critical appraisal tool to appraise your selected paper. Discuss the
reason of your choice on critical appraisal and the details of your appraised paper.
The CASP appraisal tools are well-known and readily available and accessible (CASP
Checklists, 2018). I chose a cohort study, which is one of the observational studies, in
addition to case-control studies. The article selected had a clearly stated issue and the sample
was recruited in an acceptable style by factoring in the variables of interest. The researchers
worked to minimize bias when measuring exposure by focusing on weekly averages of
alcohol consumptions compared to daily frequencies in light of the ceiling effect (Topiwala et
al., 2017). Brain outcomes were measured through the density of grey and white matters,
visual ratings using the hippocampus, and cognitive variables, all which provided a broad
approach to the outcome on focus. The follow-up period was long enough at years with an
average of 43.5 years at baseline, which could help to understand the deterioration of
cognitive function in old age. The results are believable because the methodological sequence
is credible and authors have used strategies to minimize bias, for example, minimizing the
effect of confounding factors while recruiting participants at baseline.
Module 5: Discussion Topic 2:
Comparing Screening and Surveillance Considering the methods by which surveillance data
are collected, what elements of the social context or community in which you live create
barriers to or facilitate effective disease surveillance? Feel free to draw from your personal
and professional experiences time television?

Understanding the socio-demographic profile of a certain population is one of the
surveillance data that aid in budget planning. A study by Williams-Roberts, Neudorf, Abonyi,
Cushon, and Muhajarine (2018) indicate that healthcare staff are restricted by the elements of
time, shortage of staff, lack of resources, and legal constraints that impede collection of such
information in the usual work procedures. However, advocacy and an enabling environment,
where collection of surveillance data is incorporated into an institution’s work flows, would
facilitate the collection of surveillance data. Normalization of data collection requires skilled
staff and clear policies that guide staff on the sequence and times for surveillance data
collection. As a nurse with typical responsibilities, paying attention to surveillance data
would require time set for this task or additional staff to aid in reporting because surveillance
data entails keeping tabs of the incidence and prevalence rate of conditions or other
phenomenon of interest.
Module 6: Discussion Topic 1:
Systematic Review How does a systematic review differ from the critical appraisal task set
for assessment 3? How is it similar?
A systematic review is a methodical way of summarizing evidence by using a standardized
protocol to determine the quality and acceptability of this evidence. A critical appraisal, on
the other hand, is an intense activity that entails the evaluation of a piece of scientific
literature to determine the validity and credibility of research findings in the context of the
concerned practice. A systematic review begins with laying down an articulate criteria for
article selection, but this is not case with a critical appraisal. Also, a systematic review is
guided a specific research question while a critical appraisal seek to determine the worthiness
of findings in answering a specific research question (The University of Melbourne, 2020).
Systematic reviews entail the summation of various research articles that may require a meta-
analysis, but this is not the case for critical appraisal. However, in both activities, the quality

of evidence and credibility of results is determined by reviewing the methodological
procedure.

References
CASP Checklists. (2018). Retrieved from https://casp-uk.net/casp-tools-checklists/.
Ek, A., Delisle Nyström, C., Chirita-Emandi, A., Tur, J. A., Nordin, K., Bouzas, C., …
Nowicka, P. (2019). A randomized controlled trial for overweight and obesity in
preschoolers: the More and Less Europe study - an intervention within the STOP
project. BMC Public Health, 19(945). https://doi.org/10.1186/s12889-019-7161-y.
Rosen, L., Manor, O., Engelhard, D., & Zucker, D. (2006). In defense of the randomized
controlled trial for health promotion research. American journal of public health,
96(7), 1181–1186. https://doi.org/10.2105/AJPH.2004.061713.
The University of Melbourne. (2020). Systematic Reviews. Retrieved from
https://unimelb.libguides.com/c.php?g=492361&p=3368113.
Topiwala, A., Allan, C. L., Valkanova, V., Zsoldos, E., Filippini, N., Sexton, C., ….Ebmeier,
K. P. (2017). Moderate Alcohol Consumption as Risk Factor for Adverse Brain
Outcomes and Cognitive Decline: Longitudinal Cohort Study. BMJ, 357. Doi:
https://doi.org/10.1136/bmj.j2353
Ward M. M. (2013). Estimating disease prevalence and incidence using administrative data:
some assembly required. The Journal of rheumatology, 40(8), 1241–1243.
https://doi.org/10.3899/jrheum.130675.
Williams-Roberts, H., Neudorf, C., Abonyi, S., Cushon, J., & Muhajarine, N. (2018).
Facilitators and barriers of sociodemographic data collection in Canadian health care
settings: a multisite case study evaluation. International Journal for Equity in Health,
17(186). https://doi.org/10.1186/s12939-018-0903-0