PUBH6005 Epidemiology: Examining Social Factors in Whitehall Study

This assignment provides a comprehensive analysis of the Whitehall studies (I and II), focusing on their sampling frames, disease risk assessment methods, and the extent to which their results can be generalized to other populations. The analysis covers the study design, data collection phases, and statistical methods used to assess the relationship between employment grade, work stress, and coronary heart disease (CHD). It examines biological and behavioral risk factors, including smoking, diet, and stress levels, and discusses the feasibility of conducting similar studies in Australia using existing cohorts. The assignment also highlights the social determinants of health and their impact on morbidity and mortality, offering insights into the complex interplay between socioeconomic factors and cardiovascular health. Desklib provides this assignment as a resource for students studying epidemiology, along with a wealth of other solved assignments and past papers.

Running head: EPIDEMIOLOGY 1
Epidemiology
[Author Name(s), First M. Last, Omit Titles and Degrees]
[Institutional Affiliation(s)]
Author Note

EPIDEMIOLOGY 2
Epidemiology
What is the sampling frame for each phase of the Whitehall study (Whitehall I and
II)?
In Whitehall study I, there was an investigative study of the male British civil servants in
the late 1967-1969. This was to show an inverse mortality rate. 18403 men were subjected to an
initial screening examination where they were given standard questionnaires, which they were to
fill. They were classified into administrative, professional, executive, clerical and other graded
that included the lowest status, where messengers and unskilled manual workers were
categorized. 873 were excluded on the basis that they were in the Diplomat services and British
council. Therefore, only 17530 men continued with the study. They filled in Hygiene
Cardiovascular questionnaire and standardized questions on smoking history, respiratory
symptoms, medical treatment and leisure-time activities (Marmot, 1978).
When it came to sampling of data for the Whitehall II conducted between 1985-88,
phase 1 involved recruitment of 10308 participants from 20 civil service departments in London.
For phase 2, data was collected between the years 1989-90 and phase 3 also involved data
collection from 1991-93. There was more data collection for phase 4 in 1995, 1997-99 for phase
5 and 2001 for phase 6. Phase 7 involved data collection for data between 2002-2004. For phase
3,5 and 7 there was an extra inclusion of clinical examination. On the other hand, phase 2,4 and 6
involved postal questionnaires (Chandola, 2008).
How was disease risk assessed (both in data collection and analysis) in each of the
three studies, and why?
For the Whitehall II study, there were non-fatal myocardial infarction for phases 2-7 with
or without angina. They were recorded and defined using the MONICA criteria that was based

EPIDEMIOLOGY 3
on the electrocardiogram, ECGs and cardiac enzymes. The patients who had MI at phases 1 and
2 were excluded. To enable risk free assessment, the self-reported data without clinical
verification was excluded as well. Risk factors for CJD biologically were measured at phase 3
using west circumference between > 88 cm for women and > 103 for men. Rise in glucose levels
and morning rise in cortisol were also recorded at phase 7. The heart rate was measure every 5
mins of RR for all intervals between normal to normal sinus and the domains recorded.
Behavioral risk factors for CHD inclusive of smoking, activity and diet were measured daily. At
the end of the study, only 98% of the participants were making follow ups and thus only data
regarding the present was recorded. The cox proposal hazard regression models were used in
measurements of the cumulative work stress for phases 1 and 2 and incident CHD events
adjusted for phase 2-7 in terms of employment age, smoking amongst others. The linear
regression models were used for the model association to cumulative work stress (Chandola,
2008).
For Whitewall study I, there were adjustments for age that were carried out by direct
method. More to that, the total population was standardized in order to distribute the risk factor.
The multivariate analysis used the multiple logistic equation to yield estimates of extend of
difference between grades and risk factors. The relative increase in expected risk was calculated
in terms of different phases like blood pressure amongst others. The magnitude of difference was
used to calculate the difference between the grades. Age was adjusted in order to analyze
coronary risks. Height above 5cm from the previous was used to study the CHD mortality rates
both at the beginning of the study and also during analysis. There was multivariate analysis was
used to adjust the risk factors in terms of age whereas the logistic equation was used to estimate
the effect of the risk factors in a single examination (Marmot, 1978).

EPIDEMIOLOGY 4
To what extent can the results of each of the three studies can be generalized to
other populations (include reasons for your answer)?
There is greater stress amongst the younger group of between 37-49 years as they are
more productive as compared to the 50-60 age group and thus the 0. 04 p value. The stress values
for the elder group was hardly related to work as there is not more given considering the age
group, and the need to keep the group for knowledge purposes and the diversification of work.
The young people depend on fast food for their daily energy intake and thus the high CHD levels
for the younger age group and health behaviors, as seen not only in Australia but around the
world. The mental dependability on alcohol for stress management makes it more necessary to
reducing CHD levels as opposed to the lack of it which increases thoughts and increases cortisol
levels and also blood pressure that contribute to high CHD levels as would appear in the young
working generation as opposed to the elder generation who are more cautious about their age and
the need to incorporate more healthier diets and activities in their daily lifestyle for increase of
live and reducing illnesses. Younger age groups are more vigorous in work activities and thus
spend more time working than socializing in terms of healthy physical activities and healthier
diets. This increases their stress levels and contributes to higher CHD levels. This is seen higher
in men who have an increase in smoking habits as compared to women as shown in the three
studies. The availability of variety of foods for the higher-grade men contributes to the high
plasma cholesterol levels. There limitation in free leisure activity time and increase in working
time contributes to the high poor diet choices. However, men in lower grades have higher blood
pressure due to physically demanding jobs. Lack of companionship as shown in the socio-
economic study as it is globally showed the increase in work stress and resulting to bad diet
behaviors as well as high blood pressure from the work stress (Breeze, 1969).

EPIDEMIOLOGY 5
Would it be feasible to conduct a similar study in Australia using an existing cohort
such asthe 45 and up study cohort, or the Australian Women’s longitudinal study cohort?
Why or why not? Yes.
Women tend to be all round species who engage in family, work and also other social
activities. Therefore, looking into their stress levels and the relationship between the age,
smoking habits, diets, biological habits would incorporate future methods of measuring such and
also contribute to formulation of measurement skills (Breeze, 1969).
References

EPIDEMIOLOGY 6
Breeze, E. F. (1969). Do Socioeconomic Disadvantages Persist Into Old Age? Self-Reported
Morbidity in a 29-Year Follow-Up of the Whitehall Study. Commonwealth of Australia,
1-8.
Chandola, T. B. (2008). Work stress and coronary heart disease: what are the mechanisms?
European Heart Journal, 29, 640-648.
Marmot, M. G. (1978). Employment grade and coronary heart disease in. Journal of
Epidemiology and Community Health, 32, 244-249.