HARAMAYA UNIVERSITY COLLEGE OF HEALTH AND MEDICAL SCIENCES
SCHOOL OF PUBLIC HEALTH
Epidemiology Assignment Regular MPH Program
Prepared by: Admas A
Instruction: Answer the questions and submit by hard copy with clear handwriting by the
deadline date.
1. The British Doctors study was set up in 1951 to investigate the relationship between
smoking habits and mortality. Members of the medical profession in the United Kingdom
were asked to fill in a simple questionnaire on smoking habits which was sent out to 59,600
men and women on the Medical Register.( Doll R, Peto R, Wheatley K, Gray R, Sutherland I.
Mortality in relation to smoking: 40 years' observations on male British doctors. BMJ. 1994;
309(6959):901-11).
For the initial questionnaire replies from 34440 men were sufficiently completed to be used
–that is, about 69% of the men who were alive when the questionnaire was sent. Further
inquiries about changes in smoking habits were made in 1957, 1966 and 1972. Of the initial
respondents in 1951, 17% were classified as non-smokers. At that time, the prevalence of
smoking in England was 62% in men. The following table gives death rates for men by cause
of death and cigarette smoking habit.
Table 1. Death rate for men by cause and cigarette smoking habit when last asked.
Cause of death Annual death rate per 100,000 men
Non-Smokers Current Smokers All cigarette
smokers
1-14 15-24 25+
Lung Cancer 10 78 127 251 140
Ischemic Heart 413 608 652 792 669
Disease
a. Which disease is most strongly related to cigarette smoking in the British Doctors study?
Discuss your answer.
b. Calculate separately (for the lung cancer and Ischemic Heart Disease) the proportion of
all deaths from lung cancer and from Ischemic heart disease among smokers
, attributable to cigarette smoking. What is the name of this measure and how do you
interpret it?
c. Calculate separately (for the lung cancer and Ischemic Heart Disease) the proportion of
all deaths from lung cancer and from Ischemic heart disease among men in England that
would be attributable to cigarette smoking. What do you conclude from your
calculations?
d. Does this study support the hypothesis that long term tobacco use increases the risk of
mortality? Explain your answer.
e. Describe one public health intervention that you could motivate as a result of the
findings of this study?
2. For each of the following summaries of studies, write one to two sentences that specifies
the study design and research question. You should include the main predictor and
outcome variables, and the study population.
a. Improve strength, but little is known about any influence it may have on the ordinary
weakness of aging. We selected 38 men 70 years of age and greater from a
hypertension treatment clinic and randomly 'assigned them to receive either vitamin D3
or identical placebo. Muscle strength of the quadriceps, measured with isokinetic
dynamometer after 6 months of treatment; was Similar in the two groups.
b. Knowledge about AIDS was studied among 1526 teen-aged boys and girls in 12
secondary schools in Zimbabwe. Ninety-three percent of the children thought that it
was an infection caused by having sexual relations, and about 10% said that it could be'
contracted from toilet seats.
c. The observation that mother-to-child transmission of HIV-l can occur through breast
feeding has resulted in policies that recommend avoidance of breastfeeding by ·HIV-l
infected women in the developed world. A comparison' of transmission rates in
exclusively breastfed, mixed-fed and formula-fed (never breastfed) was conducted to
assess whether the pattern of breastfeeding is a critical determinant of early mother to
child transmission of HIV-l. Infant feeding practices of 549 HIV-l infected women in a city
were assessed and proportions with risk factors of HIV infected infants at 3 months
were calculated.
d. In a study conducted in Malawi among an pregnant women after delivery, Mother-
infant pairs were randomly assigned 2369 HIV-infected breastfeeding mothers with a
SCHOOL OF PUBLIC HEALTH
Epidemiology Assignment Regular MPH Program
Prepared by: Admas A
Instruction: Answer the questions and submit by hard copy with clear handwriting by the
deadline date.
1. The British Doctors study was set up in 1951 to investigate the relationship between
smoking habits and mortality. Members of the medical profession in the United Kingdom
were asked to fill in a simple questionnaire on smoking habits which was sent out to 59,600
men and women on the Medical Register.( Doll R, Peto R, Wheatley K, Gray R, Sutherland I.
Mortality in relation to smoking: 40 years' observations on male British doctors. BMJ. 1994;
309(6959):901-11).
For the initial questionnaire replies from 34440 men were sufficiently completed to be used
–that is, about 69% of the men who were alive when the questionnaire was sent. Further
inquiries about changes in smoking habits were made in 1957, 1966 and 1972. Of the initial
respondents in 1951, 17% were classified as non-smokers. At that time, the prevalence of
smoking in England was 62% in men. The following table gives death rates for men by cause
of death and cigarette smoking habit.
Table 1. Death rate for men by cause and cigarette smoking habit when last asked.
Cause of death Annual death rate per 100,000 men
Non-Smokers Current Smokers All cigarette
smokers
1-14 15-24 25+
Lung Cancer 10 78 127 251 140
Ischemic Heart 413 608 652 792 669
Disease
a. Which disease is most strongly related to cigarette smoking in the British Doctors study?
Discuss your answer.
b. Calculate separately (for the lung cancer and Ischemic Heart Disease) the proportion of
all deaths from lung cancer and from Ischemic heart disease among smokers
, attributable to cigarette smoking. What is the name of this measure and how do you
interpret it?
c. Calculate separately (for the lung cancer and Ischemic Heart Disease) the proportion of
all deaths from lung cancer and from Ischemic heart disease among men in England that
would be attributable to cigarette smoking. What do you conclude from your
calculations?
d. Does this study support the hypothesis that long term tobacco use increases the risk of
mortality? Explain your answer.
e. Describe one public health intervention that you could motivate as a result of the
findings of this study?
2. For each of the following summaries of studies, write one to two sentences that specifies
the study design and research question. You should include the main predictor and
outcome variables, and the study population.
a. Improve strength, but little is known about any influence it may have on the ordinary
weakness of aging. We selected 38 men 70 years of age and greater from a
hypertension treatment clinic and randomly 'assigned them to receive either vitamin D3
or identical placebo. Muscle strength of the quadriceps, measured with isokinetic
dynamometer after 6 months of treatment; was Similar in the two groups.
b. Knowledge about AIDS was studied among 1526 teen-aged boys and girls in 12
secondary schools in Zimbabwe. Ninety-three percent of the children thought that it
was an infection caused by having sexual relations, and about 10% said that it could be'
contracted from toilet seats.
c. The observation that mother-to-child transmission of HIV-l can occur through breast
feeding has resulted in policies that recommend avoidance of breastfeeding by ·HIV-l
infected women in the developed world. A comparison' of transmission rates in
exclusively breastfed, mixed-fed and formula-fed (never breastfed) was conducted to
assess whether the pattern of breastfeeding is a critical determinant of early mother to
child transmission of HIV-l. Infant feeding practices of 549 HIV-l infected women in a city
were assessed and proportions with risk factors of HIV infected infants at 3 months
were calculated.
d. In a study conducted in Malawi among an pregnant women after delivery, Mother-
infant pairs were randomly assigned 2369 HIV-infected breastfeeding mothers with a
