Snow's Discovery of Cholera Cause

This document discusses John Snow's discovery of the cause of cholera, the processes involved in the scientific method, the impact of sampling error and the placebo effect, and Tversky & Kahneman's 1974 paper on decision making.

Written Project
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Table of Contents
QUESTIONS ..................................................................................................................................3
1) Describe the situation that led to Snow’s discovery of the cause of cholera ?.......................3
2) Describe the processes involved in the ‘Scientific Method’?.................................................3
3) Describe the possible impact of sampling error and the placebo effect ?...............................4
4) How did Tversky & Kahneman’s 1974 paper describe the process of decision making ?.....5
REFERENCES................................................................................................................................7
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QUESTIONS
1) Describe the situation that led to Snow’s discovery of the cause of cholera ?
John snow was born on 1813, March 15 in England. The man received the medical
apprenticeship at the age of 14. During 1832 at the middle of his apprenticeship cholera epidemic
was observed by Snow first. During such vast breakout, the man treated many individuals who
were suffering from cholera. At such period, John Snow got to understand about how the disease
transmit and what clinical symptoms it displays. In 1831 at England, the first case of Cholera
was reported which was assumed to be transmitted by 'miasma' (JOHN SNOW AND THE 1854
CHOLERA OUTBREAK, 2019). The theory of Miasma states that the disease is actually spread
by poisonous form of air which are being discharged by rotting organic matter. After completion
of all medical study, Snow became more curious about the Miasma theory and strongly believed
that dumping sewage contaminated water into rivers would further contaminate the river water to
high levels which ultimately results in causing cholera outbreaks. The man specifically
questioned local residents and workers from hospitals about whether they drank water from any
pumps, using such prior information he went to build a dot map to demonstrate the cluster of
cases which are specifically around usage of water from pumps. On 1854, John took all his
findings to the local officials of Soho and made them clear the scenarios and suggesting to take
the handle off from the pump. The officials did not listen to his theory at that moment and Joseph
Bazalgette aimed in eliminating the smell which was arising from sewage waste by making a
effective sewage system. Irrespective of such success, the outbreak of Cholera strike again who
infected large number of population. The symptoms were initiated by acute diarrhoea and
dehydration followed by greyish and bluish skin and eventual death in 48h hours. The final
epidemic proved that the theory of cholera outlined by John Snow was correct and such disease
is actually water borne. From such high involvement of Joseph and John Snow the cholera
outbreak was conquered and the sewage system was upgraded and build as per modern
metropolis. They both were responsible in saving large number of lives and introduced to whole
world that cholera is cause due to contaminated water.
2) Describe the processes involved in the ‘Scientific Method’?
Scientific method is a type of experimentation which are being popularly utilised in to
explore certain kind of observations and answer basic questions about study. Such type of
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method comprises of series of steps which must be kept in scientist mind to either backup or
repeat a certain step if the process is not done correctly. This method assist in focusing on
scientific queries and work through accurate observations and data to answer certain questions.
The first step of scientific method is to ask a question about something which has been observed
minutely. The question may focus on how, why, what, which, where, who and when. All such
parameters need to be addressed for getting a measurable or clear concept. The background
research is another step of such method which involves in making sure that the scientist make
prior research based on internet and library sources for sorting out best ways to complete or
answer the underlined question (Ferreira and et.al., 2015). Bibliography and research paper are
often utilised in this step for getting all information regarding the raised question. A hypothesis is
made which further aids in making predictions. In order to make a authenticate hypothesis,
several variables are used in formulating the study and generating potential answers for
questions. Another step of this approach is testing the generated hypothesis by conducting an
experiment. The test which are utilised in evaluating whether the prediction about questions are
right or wrong helps in supporting the hypothesis. The procedure, suitable material list are
clearly drawn on the basis of formulated hypothesis. The experiments must be repeated and
should be conducted by taking control for making sure that all test results are valid and they are
showing a fair experiment. Once the step of experimentation has been completed, scientist
analyse data by gathering appropriate information and monitor whether their data are supporting
the hypothesis or not. In some cases, researcher found that there predictions are not valid which
force them to make a new hypothesis and undergo whole process once again. If the hypothesis is
supported by derived results then suitable conclusions are made to clear the concept. The last
step of such method is to communicate the results to others in final report either by displaying in
board or by publishing the some journals.
3) Describe the possible impact of sampling error and the placebo effect ?
Sampling error has been defined as the fluctuation of chosen sample from true
characteristic, behaviour, figures, traits or properties of whole population. The error which are
occurred in sampling process is due to the fact that researcher draw various subjects from
existing population in which the individuals are different (Foroughi and et.al., 2016). The
respondents which are selected from entire population should be a representative of whole
population, thus the difference in sampling and uniformity can result in sampling error. Due to
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the resultant sampling error, the conclusion which are being drawn are not uniform and face
unevenness due to high participants difference. Biased sampling is one of the major cause of
sampling error which is highly problematic and may lead to over or under estimation of relating
variables in population. The unrepresentative sample results in failure to produce a solid support
to defined aim or objective. The most frequent outcome of sampling error is systematic error
where the results from sample highly differs from effect of whole population. Placebo have been
stratified as a component or any other certain type of treatment which look analogous to regular
medicine but actually it is an unreactive version of drug or treatment. The person who is
receiving such attention, typically have no idea about the actuality of substance which are being
administered. The impact of placebo may depend from individual to individual, the person who
have strong perception and expectations may experience positive outcome. Such individuals are
thought to get better and show lower symptoms associated to pain, stress or depression due to
placebo effects. The people on other hand who may also experience nocebo effect which is
opposite of placebo. In this, people experience negative outcome, thus it can be concluded that
effects may revolves around person's believes and dosage of medicines. If a person is acquiring
hefty medicines then an individual starts to consider that they may have an opinion that they
could suffer from any side effects due to administration of medicine. The power of such effect is
because of psychological phenomenon or person's perception which have the capacity to treat
certain level of symptoms by inactive treatment procedure.
4) How did Tversky & Kahneman’s 1974 paper describe the process of decision making ?
Heuristics have been refereed to as simplified strategies or mental processes which
individuals, some machines and organisation progressively utilise for making quick decisions as
well as to find accurate solutions to some complex and tangled issues. Tversky & Kahneman
have elaborated two heuristics which are vital in probabilistic information processing. The top
most heuristics used in the given paper is availability. As per such factor, one individual can
judge the frequency or the probability of any particular event (Morvan and Jenkins, 2017).
Availability is basically defined as heuristics that assist in making decisions about likelihood
which are based on certain events. Tversky & Kahneman illustrated an example which focuses
on judgement of investors which may change depending upon the available news and resources.
Such heuristics helps in making final decisions which are based upon available knowledge that is
promptly available in minds rather than evaluating all possible alternatives. Most of the time it
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has been analysed that people use availability heuristic without even realising in forming a
crucial judgement. Anchoring and adjustment are another heuristics which are being utilised in
specified paper to make authenticated decisions. Such type of heuristics centres on underlining
the bases of individual which comprises of their initial concept and responses on one specific
point of data and further alterations are made from starting. By the help of such heuristics an
individual uses certain values or numbers as an initial point which are known as anchor and
ultimately adjust the data until an acceptable value have been achieved over time. The
researchers have demonstrated that setting an anchor at initial stage can have a major effect on
final result which eventually aids in making best decisions under such dynamic situation. These
cognitive bias which make can individual to rely on initial point so much that they can make
decisions by suing such piece of information. During decision making process, anchoring is used
for making subsequent judgements. These heuristics as per the specified author are mental
shortcuts which are specifically used in making critical decision and all possible judgements that
are highly influenced by cognitive and emotional state.
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REFERENCES
Books and Journals
Ferreira, F. K. & et.al., (2015). New mindset in scientific method in the health field: Design
Thinking. Clinics, 70(12), 770-772.
Foroughi, C. K. & et.al., (2016). Placebo effects in cognitive training. Proceedings of the
national Academy of Sciences, 113(27), 7470-7474.
Morvan, C., & Jenkins, W. J. (2017). Judgment under Uncertainty: Heuristics and Biases. Macat
Library.
Online
JOHN SNOW AND THE 1854 CHOLERA OUTBREAK. 2019. [online]. Available
through:<https://www.pastmedicalhistory.co.uk/john-snow-and-the-1854-cholera-outbreak/>
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