MCCEE

Env 1 What is the most common source of mercury poisoning in Canada


Fish

Thermometer industry

Dentists

inhalation

Fish

Env 2 who are the most exposed group to mercury poisoning in Canada

native Indians

Native Indians

Env 3 Which is NOT true regarding O3 (Ozone)?

-Increased around photocopy machine

-Can be harmful at ground level

-It’s mainly due to incomplete combustion of fossil fuels

Increased around photocopy machine

Env

Ra

4 Which is true regarding the side effects of radiation?

-Microwaves cause superficial burns

-Laser radiation can cause retinal burns

-UV can cause Alopecia Areata

-Beta ray can cause Leukemia

-Delta ray are dangerous for the central grey nucleus

Beta rays (or any other ionizing

radiation) can cause Leukemia

Env

Ra

5 Which of the following is true regarding non-ionizing radiation?

-Can cause Chronic bronchitis

-Can cause Loss of vision

-Can cause cataract

Near-UV (UV-A; 315-400 nm) causes

Cataract

Env

Ra

6 The commonest source of radiation exposure is

-Background exposure

Natural background radiation ~ 90 %

of all radiation sources

Env

Ra

7 Surveillance in medical worker for radiation hazard include all EXCEPT:

-Hematological examination

-Annual PE.

-Labeled panding (?!)

-Total body radiation count

Labeled panding (?)

epi 8 A new vaccine against measles is being evaluated. The following results of one full

year of study:

Diseased Healthy %

Unvaccinated 137 378 36.3

Vaccinated 51 266 19.2

What is the vaccine efficacy (VE)

-17.9 %

-47.0 %

-21.8 %

-36.3 %

47%. The Vaccine efficacy formula=

Incidence(vacc)-Incidence(unvacc) ÷

Incidence(unvacc)

=(36.3-19.2) ÷ 36.3=47%

If Incidence(vacc)=Incidence(unvacc) then

VE=0 ÷ Incidence(unvacc) =0%

If Incidence(vacc)=0 then

VE= Incidence(unvacc)-0 ÷

Incidence(unvacc) =100%

Epi 9 Which of the following is the least indicative of causality

temporal relation

Consistency

Biological plausibility

Analogy to similar conditions

Analogy; See the Bradford Hill

“criteria” for causality

Epi 10 Causality can be assessed by

Cohort study

Case-control study

Cross-sectional study

Both cohort and case-control studies.

Both cohort and case-control studies

Epi 11 Characteristic of the placebo effect. All true EXCEPT:

-50% effective

-Patients believe in treatment efficacy

-It is greater in IM than in PO.

-It decreases if used frequently because of dependence

-Naloxone effect shows that placebo effect occurs by inhibition by morphinic

receptors

(?) It decreases if used frequently

because of dependence

Epi 12 In placebo treatment. All are true EXCEPT:

-Response to placebo indicates that the cause is psychogenic

-Repeated use decreases its efficacy

-1/3 of those with organic causes respond to the placebo

Response to placebo indicates that the

cause is psychogenic

Epi 13 Study has been done between a risk factor and a disease, the odds ratio was 2.3 (p

value=0.4). What is true?

-There is significant association between risk factor and disease.

The association could have been due to

chance

2

-The disease is 2.3 times more in those having risk factor

The association could have been due to chance

Epi 14 What is the relative risk in the following cohort study: death in smokers= 1/1000,

death in non-smokers 0.05/1000.

1/1000 ÷ 0.05/1000

1/1000 ÷ 0.05/1000 x 5

1/1000 ÷ 0.05/1000 = 20

Epi 15 A study reveals that 10 yrs experienced drivers contributed to 60% of accident. 5 yrs

experienced drivers contributed 30% and those with 2 yrs contributed 10%. The

conclusion was that the more experienced drivers are more careless in driving. This

conclusion is not right because:

- Study did not measure the incidence of accidents

- Study not age-standardized

-Because there is no control group

Study did not measure the incidence of

accidents—Unlike prevalence,

incidence rates take the duration of

driving in consideration.

Epi 16 Study about the benefit of exercise in decreasing the risk of heart disease applied to a

group of volunteers in a factory with the rest of the factory employees representing

controls. Follow up was regular. The study shows lower rate of IHD (Ischemic Heart

Disease) in the exercising group. The conclusion: exercise protect against IHD may

be rejected because of:

-Selection bias

-Only men were included

-Only one company was involved

-Some IHD may be silent

Selection bias. The exercise group are

self-selected (volunteers) and are likely

to be different in other ways (other

than exercising)

Epi 17 Case-control study useful in:

Study of rare disease.

Study of common disease.

Does not provide odds ratios

It includes the whole population

Study of rare disease

Epi 18 A cohort study, which is true:

The study should start with all persons at the same time regardless of the appearance

of signs and symptoms

They should start when the signs and symptoms appear

should start when complications appear

The study should start with all persons

at the same time regardless of the

appearance of signs and symptoms

Epi 19 A cohort study, all are true except:

Relative risk can be calculated.

Incidence rate can be calculated.

Attributable risk can be calculated.

Prevalence rate can be calculated.

Prevalence rate can be calculated

Epi 20 Best sample for a study is taken from:

the general population

hospitals

the general population

Epi 21 In a cross-sectional study of 15-49 years old, peptic ulcer was more common among

females compared to males. The study findings can’t be generalized because:

there was no control group

limited to certain age group.

limited to certain age group

Epi 22 A researcher has planned to include 100 individuals in her study but she could only

recruit 75. She found a p value > 0.05 and concluded that the results are clinically

insignificant. What was worrying about this study:

a) She mixed between clinical and statistical significance.

She mixed between clinical and

statistical significance. Also the study

lacked power to detect meaningful

differences

Epi 23 You gave a new drug for hypertension to your patients. Those suffering from multiinfarct

dementia improved while those with Alzheimer’s did not. You want to give

this drug to your patients in the clinic. What type of trial is this?

a) Phase 1trial

b) Phase 2 trial

c) Phase 3 trial

Not totally clear but most likely answer

is Phase 3 trial

Epi 24 Randomization can limit all the following except

a) Known confounders

b) Unknown confounders

c) Selection bias

(?) Randomization can limit all three

Epi 25 Relation between asbestosis and smoking is called:

-Additive

-Synergistic

-antagonist

Synergistic

epi 26 Patient with history of HT and DM had an acute MI and died due to cardiac arrest. MI

3

Cd In writing the death certificate, what is the immediate cause of death?

-DM.

-HT.

-MI.

-Cardiac arrest

Cardiac arrest is the mode of death.

epi

Cd

27 Patient with breast CA underwent operative surgery and chemoradiotherapy, she

developed pneumonia followed by death. What is the underlying cause of death?

-complications of chemotherapy

-Breast CA

-Pneumonia

Breast ca.

epi

Cd

28 Patient died after suffering from TB, what will you write in death certificate as a

cause of death?

-Cardiac arrest

-TB

-Fever

-Loss of weight

TB

epic

d

29 An alcoholic and diabetic had active TB. Developed pneumonia and died. What will

you write in death certificate as underlying cause of death?

- Pneumonia

-TB

-Diabetes

-Old age

TB

Epi

d

30 A new test for CA Cervix allows better detection. All can be modified EXCEPT:

-Prevalence

-Incidence

-PPV

-NPV

-Survival rate

(?) All can be modified assuming that

better detection means better test

sensitivity and specificity. I would go

with survival rate assuming that better

detection does not mean that screening

works

Epi

d

31 Screening is useful in

rare untreatable disease

long time asymptomatic but treatable

long time asymptomatic but treatable

Epi

d

32 Which one of the following descriptors of a diagnostic test is influenced by the

prevalence of the disease being tested for:

-Specificity

-Sensitivity

-Accuracy

-Positive predictive value

-Reliability

Positive predictive value and so is

negative predictive value

Epi

d

33 Threshold of a screening test is increased. This will affect the test in terms of:

-Increased sensitivity and specificity

-Increased No. of FP.

-Increased No. of FN.

-decreased sensitivity and increased specificity.

decreased sensitivity and increased

specificity

Epi

d

34 Threshold of a screening test is increased. How it will affect sensitivity and

specificity?

a) Sensitivity increase and specificity decrease

b) Sensitivity decrease and specificity increase

Sensitivity decrease and specificity

increase

Epi

d

35 What will be the effect of increasing the prevalence of a disease for a screen test?

-Increase in the sensitivity of the test

-Increase in the specificity of the test

-Increase in the PPV.

-Increase in the NPV.

-Increase in the sensitivity and PPV. of the test

Increase in the PPV

Epi

d

36 What will increase false positive results?

-Increase in prevalence and decrease in the specificity of the test

-Increase in prevalence and decrease in the sensitivity of the test

-Decrease in prevalence and increase in the sensitivity of the test

-Increase in prevalence and increase in the sensitivity of the test

Increase in prevalence and decrease in

the specificity of the test

Epi

d

37 Liver on autopsy was found to be shrunken. During his life, the patient was told by

different physicians that he had a normal liver. How would you describe this test?

Good reliability, poor validity

Poor reliability, poor validity

Good reliability, poor validity

Epi 38 If sensitivity is 80% and specificity is 90%. What is the PPV: can’t be calculated

4

d 50%

70%

82%

can’t be calculated

Epi

d

39 Regarding screening for breast ca, all decrease except

Prevalence

Incidence

mortality

Incidence, but prevalence may not

necessary go down.

Epir 40 Population pyramid, what is true:

Age and sex distribution trend

Age and sex distribution over time

Age and sex distribution at one time

Age and sex distribution at one time

Epir 41 Definition of potential years of life lost (PYLL)

Epir 42 Definition of age-specific mortality/morbidity rate

Epir 43 Definition of average hospital stay

Epir 44 Definition of life expectancy

Epir 45 Definition of Prevalence: total number of cases in a population at a given time.

Epir 46 Definition of Crude birth rate

Epir 47 The prevalence of disease decreases while incidences increases when:

the chronic disease is treated by more facilities

the disease is being early detected and treated

the disease is being early detected and

treated

Epir 48 All are true regarding incidence EXCEPT:

-Take only the new case in consideration

-Estimates the risk of acquiring the disease in community

-Useful measure of disease burden in community

-Useful for both acute and chronic disease

Useful measure of disease burden in

community—that is the prevalence

Epir 49 The natural growth rate =

-Birth rate - immigration rate

-Birth rate - death rate + net migration rate

-Birth rate + immigration rate

-Birth rate - death rate + net migration

rate

net migration rate=Immigration rate -

Emigration rate

Epir 50 Study shows that specific mortality rate for stomach CA tends to decrease. What is

the most likely explanation?

-Decreased Prevalence

-Decreased Incidence

-Better screening

-Better treatment

Decreased Incidence also better

treatment

Epir 51 If a child develops diphtheria now the mortality is almost the same as it was 50 years

ago. But now the mortality rate is very low because

a) Incidence decreased

b) Prevalence decreased

c) Effective antibiotics developed

Incidence decreased

Epir 52 prevalence is affected by all except:

Incubation period of disease

Case fatality rate

duration of illness

incidence

Epir 53 In a study, the perinatal mortality rate among those who had home delivery was

lower than those who had hospital delivery. You will consider these results:

Correct

Incorrect because is no confidence interval

Incorrect because the 2 groups are not comparable

Incorrect because the 2 groups are not

comparable

Epir 54 What is the best way to appreciate health care quality during pregnancy and delivery

in Canada?

-Neonatal mortality rate

-Perinatal mortality rate

-Infant mortality rate

-Maternal mortality rate

Perinatal mortality rate

Hp 55 Most important Dietary modification of middle-aged group is:

-Total calorie content

-Fiber diet

-Carbohydrates content

-protein

(?) Fiber-rich diet.

5

Hp 56 Life expectancy is increased in Canada due to:

-Decreased infant mortality rate

-Availability of Diagnosis and treatment

-Improved socioeconomic status

-Antibiotics era

Improved socioeconomic status

Hp 57 Form 1971 to 1992 life expectancy for men has increased from 68 to 73 years,

women from 73 to 81 years. What is the most likely cause of these changes?

-Vaccination

-Better management of ischemic diseases

-Use of antibiotics

-Improvement of life style

-Generalization of health care

Improvement of life style

Hp 58 The most important cause of increased complications of measles in developed

countries is:

-Inadequate immunization

-Inadequate nutrition

Inadequate nutrition

Hp 59 Tertiary prevention is

-Rehabilitation.

Rehabilitation.

Hp 60 all the following are primary prevention except:

-Immunization

-Health related education

-Pap smear

Pap smear

Hp 61 What’s the best criterion for estimating population health?

-Amount of money spent on health

-GDP

-Ratio of physicians per habitant

-Number of hospitals

(?) not clear

Hp 62 WHO conference in 1978 in Alma Mata, Russia- declaration on

a) Primary health care

b) Polio eradication by 2005

c) Small pox eradication

Primary health care

Hp 63 Health promotion is defined as

Enabling people to increase control and to improve health

Hp 64 Which of the following is the most effective way to prevent dental caries in children?

a) Fluoridation of water

b) Dental flossing

Fluoridation of water

Hp 65 Periodic health examination not true

a) Detection of chronic diseases

b) Behavior change and hygiene

c) More focused annual physical examination

(?)More focused annual physical

examination

Hp 66 All of the following are done at the community level except:

Oral polio vaccine

Prophylaxis for malaria

Prophylaxis for malaria

Hp 67 A man drinks, smokes and puts his seatbelt 75% of time, what will increase his life

expectancy:

Stop drinking

Stop smoking

Put his seatbelt 100% of the time

Stop smoking

Risk of death from smoking 1:200;

recommendation A

Risk of death from RTA 1:17000

recommendation B

Hp 68 Culture shock can be reduced by:

Intact family

Rapid integration within community

Psychiatric help

Financial support

(?)Rapid integration within community

Hs 69 Which one of the following affects the outcome and future planning of Canadian

health program?

-Accident

-Age

Age

Hs 70 What population group is expected to increase in Canada next years?

-Neonates

-10-15 years.

-20-40 years.

-40-65 years.

-Above 65 years.

Above 65 years

6

Hs 71 Which will increase day care load in the next decade?

-Heart disease

-CA.

-Dementia

-Accident

Dementia

Hs 72 The following disease are more frequent in poor than in rich Canadians EXCEPT:

-Suicide

-Coronary heart disease

-Lung CA

-Stroke

-Breast CA

Breast CA

Hs 73 Why high socio-economic status is associated with less morbidity and mortality

More education

Economic status

Better child care

(?) More education

Hs 74 Which of the following does not cause mortality difference in Canada?

Unemployment

living in a village

smoking

(?) living in a village

Hs 75 The most important cause of difference between male and female mortality rates is

due to:

-Accident

-Puerperal

-suicide

Accident

Hs 76 All the following causes of death are different between men and women except:

-Accident

-Ca breast

-CVA

-IHD

-Liver cirrhosis

Liver cirrhosis

Hs 77 Information about mortality in Canada can be obtained from

-Canada statistics

-Public health center

-Out Patient clinic

Canada statistics

Hs 78 Information about morbidity in Canada can be obtained from

-Canada statistics

-Public health center

-Out Patient clinic

Canada statistics

Hs 79 Which is the commonest cause of mortality in children aged 5 to 9 years in Canada?

-Leukemia

-Cancer

-Accidents

-Congenital malformation

Accidents

Hs 80 The leading cause of PYLL loss is

-IHD

-Cancer

-Accident

Depends on age but generally cancer is

the leading cause

Hs 81 The most common cancer in Canada?

a) Lung

b) breast

c) prostate

d) Brain

e) Skin

Skin

Hs 82 The most common cancer incidence in Canadian men (excluding skin)?

a) Lung

b) prostate

c) colorectal

d) thyroid

e) stomach

prostate

Hs 83 The second common cancer mortality in Canadian women

a) Lung

b) breast

c) colorectal

breast

7

d) ovary

e) Uterus

Hs 84 The most common cause of death among children 1-4 yrs of age

burns

MVA

Drowning

Homicide

suicide

MVA

Hs 85 The most common cause of death among men under 30

Accidents

cancer

Homicide

suicide

Accidents

Hs 86 The most common cause of death among children under 1 year of age

congenital anomalies

(?) perinatal conditions

Hs 87 The most common cause of death among aboriginal men

trauma and poisoning

trauma and poisoning

Hs 88 Aboriginal Canadians have higher risk

Infant mortality

Hs 89 which of the following is the most common condition in Canada

a) cervical malignancy

b) endometrial malignancy

c) endometrial polyp

d) septulum uterus

(?) endometrial polyp

Inf 90 Young girl presents with fever, conjunctivitis, developed rash in her neck, cheeks

and malar area. Whitish spots in buccal mucosa. What is your first step:

notify public health

check immunization status of all peers

check immunization status of your pregnant secretary

start vaccination in school

Measles; notify public health

Inf 91 All the following are causes of variable incubation period except:

Herd immunity

Immunization

Host resistance

Mode of transmission

Herd immunity

Inf 92 Epidemic curves All kinds of curves

Inf 93 After eliminating measles, what could be reduced:

Immunization

Reporting of new cases

Surveillance of new cases

Hospital cost spent on measles treatment

Hospital cost spent on measles

treatment

Inf 94 Food poisoning after food by 3 hrs. Cause?

a) Staph.

Inf 95 In case of food poisoning; what action?

verify with other GPs

verify with lab staff

Notify public health

Notify public health

Inf 96 Isolation of disease depends on?

Infectivity of the disease

Length of incubation period

(?)Infectivity of the disease

Inf 97 Most important factor in food poisoning

Food handlers hygiene

Oc 98 The most common cause of sick leave

back pain

Headache

Accidents

back pain

oc 99 Of the following CA. Which one is caused by vinyl chloride:

-Lungs

-Esophagus

-Rhinopharynx

-Liver

-Bladder

Liver

Oc 100 The following are carcinogenic EXCEPT: Fat

8

-Fat

-Monosodium glutamate

-Benzene

-Nickel

-Arsenic

Oc 101 All are carcinogenic EXCEPT:

-Uranium

-Arsenic

-Radon

-Chromium

-Lead

Lead

Oc 102 The following are matched EXCEPT:

-Nut chewing and mouth cancer

-Alcohol and esophageal cancer

-Nickel and liver cancer

-Radiation and leukemia

Nickel and liver cancer

Oc 103 In which case occupational deafness is mostly suspected

-Unable to hear the bell sound at 3 m.

-Decreased in hearing high intensity voices

-Decreased peak at 4000 hertz on the audiogram

-Deafness at speaking voice

Decreased peak at 4000 hertz on the

audiogram is characteristic

Oc 104 Occupational deafness, usually caused by

-high frequency loss

low frequency loss

High frequency loss

Oc 105 Which is the most practical measure to reduce occupational deafness?

-The usage of daily prophylactic ear plugs during duty

-Measuring the noise frequency

-Usage of ear protection

The usage of daily prophylactic ear

plugs during duty

Oc 106 Most common source of silicosis exposure in Canada is:

-Sandblasting

-Coal dust

-Brake lining

-High concentration of Gases

Sandblasting

oc 107 Which is the most likely to be associated with Leukemia?

-Aromatic hydrcarbones

-Ionized radiation

-Benzoalphaperines

Ionized radiation

Oc 108 The most common occupational disease in Canada.

a) silicosis

b) dermatitis

c) asthma

d) Asbestosis

e) Carpal tunnel syndrome

dermatitis

Oc 109 TB can occur as a complication of:

Silicosis

Asbestosis

Lead

Coal

Silicosis

Oc 110 which is not a cause for occupational asthma.

a) Vinyl chloride

(?)

Oc 111 Which causes nasal sinus ca.

a) Nickel

b)

Oc 112 A man working in tree cutting presented with numbness and pain in both hands.

Which is true:

a) The symptoms are most likely due to his work

The symptoms are most likely due to

his work

Oc 113 How to prevent lead poisoning among workers in a battery factory

Hand wash before eating

Shower after finishing

Protective gear (gloves etc)

Good ventilation

(?) hand wish or ventilation

Oc 114 The most common cause of dermatitis is

Occupational

Atopic

9

Allergic contact

atopic

diaper

Oc 115 Workers with video display terminal are susceptible to

cancer

cataract

dermatitis

deep thermal injury

(?) none of those. Mostly eye fatigue

and muscular sprains. Cataract is not

confirmed.

Oc 116 The best way to prevent muscular sprains and strains at work

ergonomic engineering

gloves

sprints

treatment and rehabilitation

ergonomic engineering

Oc 117 A worker in a chemical factory presented with clear picture of hepatitis and contact

dermatitis. He denies that other workers have the same illness. What action

Notify public health

Visit place of work

Notify public health

Oc 118 Byssinosis is an occupational disease seen in

Workers in cotton factory

In sugar canes

Workers in cotton factory

Oc 119 In Byssinosis

Bronchoconstriction occurring in cotton workers

May lead to emphysema and irreversible bronchoconstriction

Unlike asthma, symptoms decrease with repeated exposure

Byssinosis is a chronic, asthma-like narrowing of the airways. Results from inhaling particles

of cotton or jute. Symptoms are usually more pronounced when returning to work after a

weekend and subside as the worker becomes reaccustomed to the environment. Prolonged

exposure can cause chronic bronchitis. It does not lead to permanently disabling lung disease.

May lead to emphysema and

irreversible Bronchoconstriction

Org 120 Who is ultimately responsible for the (standard) health care quality?

-Board of directors

-Staff

-Chief physician

-Chief of staff

(?)Board of directors

Org 121 The biggest budget percentage goes to:

Hospitals

Doctors

Labs

Hospitals

org 122 What is the allowed amount of GNP (gross national product) to health in Canada?

-4% - 8%

-8 % - 12 %

-12 % - 15 %

-16 % - 24 %

-25 % - 36 %

8 % - 12 %

Org 123 What is the rule of Royal collage of Canada?

-Credentialing body (certification of specialist)

Org 124 About the licensing authority. Which of the following is true?

a) Interest of public is most

Org 125 What is the policy of Canada to decrease the health expenditure?

-Advise the health professional to use the health resources

org 126 All the following are function of public health except:

Health promotion

Immunization

Control of the conditions at workplace

(?)Control of the conditions at

workplace

Org 127 Who pays for health care of aboriginals?

a) Federal government

Org 128 Concerning the function of provincial/territorial health care all is true except

Immunization

Long term and home care

Public health policy

Surveillance

(?)Public health policy

Org 129 A hospital with long waiting list reduced length of stay what will be the effect

Decrease in nursing staff

Decrease in occupancy rate

(?)Decrease in occupancy rate

10

Decrease in use of diagnostic services

Increased access for emergency cases

Org 130 Concerning Canada health act,

Expenses of health care are portable between provinces

Every one has access to medical insurance

All true: comprehensiveness, coverage,

universality, portability

Ra 131 Which of the following radiation has the deepest penetration in human tissue:

-Alpha

-Gamma

-X-ray

-Delta

-UV

Gamma also x-rays

sm 132 Nicotinic skin patchy is contraindicated in:

-Pregnancy

-CVA

-Ischemic Heart disease

-Alcoholic

NB. (not sure)

Pregnancy

Sm 133 A smoker tries to quit many times last year, what age group he is most likely in

-40s

-30s

(?)

Sm 134 What is true regarding smoking restriction in public places?

-Decreases the incidence of chronic respiratory disease

-Decreases the incidence of allergic respiratory disease

-Decreases the incidence of cardio vascular disease

-Shortens hospital stay

(?) All except shortening hospital stay

sm 135 Smoking withdrawal which of the following is the most common symptom:

-Insomnia

-Tachycardia

-Anorexia

Insomnia (but irritability is the

commonest)

Sm 136 Regarding smoking cessation. All are true EXCEPT:

-Decreased lung CA occurrence as other nonsmoking population by 2-3 years of

cessation

-Improvement of claudication

3 years after quitting: risk of heart

attack is the same as for a non-smoker

10 years after quitting: lung cancer

risk is halved

15 years after quitting: health is

effectively the same as a non-smoker

Sm 137 All the following tumors associated with TOBACCO use except

-Bladder

-Esophagus

-Liver

-Cervix

-Lung

Liver

Sm 138 The least effective smoking prevention measure in schools:

use of resistance skills

reduced sales to minors

Frequent sessions

(?)reduced sales to minors

St 139 Experimental study done with 2 drugs, shows that the result is significant, the

epidemiologist wrote in his report that “p” is less than 0.5. What does that mean?

-The association is less than 1\20 (5%) likely to be due to chance alone

st 140 The test used to compare 2 means:

T-test

Q-square test

T-test

st 141 A new anti-hypertensive drug was given to a group of volunteers. What of the

following is used to study the effect of the drug before and after treatment

T-test

Q-square test

Pearson correlation

Paired T-test

Paired T-test

St 142 70% of women in North America use tampons. In a sample of 36 Canadian women

who had toxic shock syndrome, 35 were using tampons. A chi-Square test was

significant (since 70% of 36 =25). The conclusion that TSS is associated with use of

tampons is:

not justified because there was no

control group

11

justified

not justified because chi-square test was misinterpreted

not justified because observer bias was committed

St 143 In a small town. The incidence of disease A is (iA) 8\1000. The disease B not

related to disease A has an incidence of (iB) 12\1000. What is the probability that

the Patientwill have both of the disease In the same time?

-iA + iB

-iA X iB

-(iA + iB) \ 1 - (iA + iB)

-(iA + iB) \ 2

-(iA + iB) \ (iA - iB)

iA X iB

Tr 144 Best prophylaxis for a Canadian traveling to a Malaria area with no resistant strains

is:

Chloroquine

Meflaquine

Meflaquine

Tr 145 Best advice for a Canadian traveling to an area endemic of cholera:

Cholera vaccine

Avoid drinking unboiled water and uncooked food

Prophylactic antibiotics

Avoid drinking unboiled water and

uncooked food

Va 146 Which of the following is the least effective vaccine:

-BCG.

-MMR

-HBV

-Pertussis

Pertussis or BCG; Vaccine efficacy of

Pertussis: 35%-96%

BCG: 0%-80%

Others > 90%

Depends on population etc

Va 147 All are live attenuated vaccine except:

-BCG.

-Yellow fever

-Polio

-Measles

-Diphtheria

Diphtheria is toxoid

Va 148 How often do u give a booster in people previously adequately immunized against

tetanus:

-Every 10 years

Td given every 10 years to adutls

va 149 All are included in the routine immunization EXCEPT:

-Measles

-Pneomococus vaccination

-Mumps

-Rubella

Pneomococus vaccination

Va 150 which of the following diseases can be prevented by a live attenuated vaccine except

a) typhoid

b) measles

c) polio

d) rubella

e) diphtheria

diphtheria

Va 151 which of the following diseases can be prevented by a vaccination except

a) Mumps

b) measles

c) Roseola

d) rubella

e) diphtheria

Roseola

Va 152 Which of the following vaccine causes more side effect:

-Pertussis

-Measles

-Diphtheria

-Yellow fever

Pertussis

Va 153 The vaccine which is given to adults (or recommended every 10 years) is:

-DT Pertussis

-Td

-T

-DT and Polio

Td

va 154 Pertussis vaccine is contraindicated in

-Egg allergy

-Encephalitis after the previous dose

Encephalitis after the previous dose

12

-Upper respiratory tract infection with slight fever

va 155 influenza vaccine is contraindicated in

One year old

congenital immunodeficiency

acquired immunodeficiency

Under 6 months

Under 6 months

Va 156 About live attenuated vaccine, all true except

a) they are save in patients with AIDS

b) In pregnancy they may cause problems

In pregnancy they may cause problems

Va 157 Haemophilus influenza vaccine is:

a conjugate vaccine

killed vaccine

live attenuated vaccine

a conjugate vaccine

Va 158 Which of the following is passive immunization:

diphtheria

Rabies

Rabies

Va 159 MMR is used in all following except

Nephritic syndrome on perdinsone treatment.

Va 160 Live attenuated vaccine. All true except

Can give life-long immunity

Can not be given in immunodeficiency

Produce infection as naturally acquired diseases

xGe

n

161 An autosomal recessive disease is present in a community at the rate

1:40000.What is the probability of any two marrying to get a child with the

disease?

-1:200

-1:400

-1:4000

-1:40000

Or what is the prevalence of the defective allele.

Answer in this case is 1:200

I think the answer is d, 1:40000.

This is a question about Hardy-

Weinberg equilibrium

(population genetics; See

Davidson’s Principles and

Practice of Medicine for

details). Briefly, for an

autosomal recessive disease (eg

cystic fibrosis), two mutant

alleles are needed for the disease

to develop (one good allele is

enough to maintain function).

Suppose that the frequency

(prevalence) of the mutant allele

is p and that of the normal allele

is q, a population is in Hardy-

Weinberg equilibrium if it

satisfies the following equation:

p2 + 2pq + q2 =1

Now p2 is the proportion of

people who would have 2

mutant alleles and therefore

have the disease. It was given

that p2= 1:40000 or 0.000025.

So p or the prevalence of the

mutant allele is equal to the

square root of 0.000025 = 0.005.

If 2 random people marry, each

has a probability of 0.005 to

carry the mutant allele. From the

multiplicative law of

probability, the probability that

their child will receive both

13

mutant alleles is 0.005 X

0.005= 0.000025 or 1:40000.

PS: Multiplicative law of

probability: The probability of

the joint occurrence of two

independent events = product of

their separate probabilities OR

p(X,Y) = p(X) * p(Y)

xGe

n

162 A lady carrier of an X linked recessive disease marries a normal man. They have 2

daughters. What is the probability of each of them of becoming a carrier?

a) 1 in 4

b) 1 in 8

c) 1 in 16

d) 1 in 64

The probability that a girl will become

a carrier is 50%. The probability of

both of them becoming carrier is ½ x

½ =1/4 (25% or 1 in 4)

xGe

n

163 The tree of autosomal dominant transmission

Xge

n

164 A woman consults you because of a possibility of her offspring having Huntington’s

Chorea. Her father is affected. Her husband family doesn’t have this disease What is

the possibility that her children will develop the disease?

-50 %

-0 %

-25 %

-100 %

(?) The probability that this woman

carries the gene is 50%. Given that the

husband is not a carrier, 50% of their

children will receive the gene. Given

only this information, 25% of children

will receive the gene (and develop the

disease since Huntington’s is

dominant)

XG

er

165 Elderly Patient : Prefer to sit home and to be visited by relatives.

XG

er

166 The most common dental disease in elderly

Peridontitis

All are true except:

a_one indirect measure of the population's health status is the percentage of low birth weight

neonate

b_accidents are the largest cause of potential year of life lost in canada

c_the canadian population is steadily undergoing rectangularization of mortality

d_morbidity is defined as all health outcomes excluding death

e_ the neonatal mortalilty rate is the number of infant deaths divided by the number of live

births multiplied by 1000

D

In Canada the admissions for the following cases are going to increase in future as a major

health problem .

1. Accidents.

2. Malignant diseases.

3. Senile dementia.

4. Disabled old patients.

Five physicians are deliberating over whether the patient they have

> examined is exhibiting the auscultatory signs of mitral valve prolapse or

> not. Assuming that there would be agreement by chance of 50%, but, in

> fact, four of the five physicians actually agree on the findings, what is

> the choice-corrected agreement (kappa) for the clinical findings?

> 1) 0.8

> 2) 0.75

> 3) 0.6

> 4) 0.7

> 5) 0.5

Kappa is measure of agreement

(between 2 or more observer) that is

more than expected by chance.

Kappa = (Observed - Expected

agreement) / (1 - Expected agreement)

Kappa= ( 0.8 – 0.5) / (1-0.5) = 0.3 /.5

= 0.6

93-1.0 Excellent Agreement

0.81-0.92 Very good agreement

0.61-0.80 Good agreement

0.41-0.60 Fair Agreement

0.21-0.40 Slight Agreement

0.01-0.20 Poor Agreement

= 0 No Agreement

The incidence of an autosomal recessive disorder is 1 per 2500 live births. Assuming This is not strictly public health. It is

14

that the population in a given community is relatively isolated and homogeneous,

what is the recessive gene frequency for unaffected individuals in this community?

1) 1 in 1250

2) 1 in 500

3) 1 in 250

4) 1 in 50

5) 1 in 25

more of a genetics question. But I

agree with you that ph questions could

be hard. But if you know the answer

that will guarantee you a high score

because hard questions carry more

weight. I’ll try at least to explain what

I understand about this MCQ.

Hardy-Weinberg equilibrium could be

explained as follows: for an autosomal

recessive disease (eg cystic fibrosis),

two mutant/defective alleles are

needed for the disease to develop (one

good allele is enough to maintain

function). Suppose that the frequency

(prevalence) of the mutant allele is p

and that of the normal allele is q, a

population is in Hardy-Weinberg

equilibrium if it satisfies the following

equation:

p2 + 2pq + q2 =1 ;

This equation comes simply from

multiplying (p+q) for the mother with

(p+q) for the father (random mating of

2 people) which will give p2 + 2pq +

q2. The equation says that:

1) The percentage of people

homozygote for the mutant allele (and

therefore will develop the disease

because both alleles are defective) = p2

(square of the prevalence of the mutant

allele or p).

2) The percentage of people

homozygote for the normal allele= q2

(square of the prevalence of the normal

allele or q).

3) The rest will be heterozygoes. But

they will not develop the disease b/s as

we said this autosomal recessive

disease.

Now p2 is the proportion of people

who would have 2 mutant alleles and

therefore have the disease (in this case,

this is 1 per 2500 live births). But p is

the prevalence of the mutant allele. So

to find out the prevalence of the mutant

allele we will just have to take the

square root of 1 per 2500 and that will

give the answer.

Live attenuated vaccines

Live attenuated vaccines usually are created from the naturally occurring germ itself. The germs used in these vaccines still can

infect people, but they rarely cause serious disease. Viruses are weakened (or attenuated) by growing them over and over again in a

laboratory under nourishing conditions called cell culture. The process of growing a virus repeatedly-also known as passing--serves

to lessen the disease-causing ability of the virus. Vaccines are made from viruses whose disease-causing ability has deteriorated

from multiple passages. Examples of live attenuated vaccines include:

1. Measles vaccine (as found in the MMR vaccine) 2. Oral polio vaccine (OPV)

3. Mumps vaccine (MMR vaccine) 4. Varicella (chickenpox) vaccine

15

5. Rubella (German measles) vaccine ( MMR vaccine)

Inactivated (killed) vaccines

Inactivated (killed) vaccines cannot cause an infection, but they still can stimulate a protective immune response. Viruses are

inactivated with chemicals such as formaldehyde. Examples of inactivated (killed) vaccines:

Inactivated polio vaccine (IPV), which is the shot form of the polio vaccine

Inactivated influenza vaccine

Toxoid vaccines

Toxoid vaccines are made by treating toxins (or poisons) produced by germs with heat or chemicals, such as formalin, to destroy

their ability to cause illness. Even though toxoids do not cause disease, they stimulate the body to produce protective immunity just

like the germs' natural toxins. Examples of toxoid vaccines:

Diphtheria toxoid vaccine (may be given alone or as one of the components in the DTP, DTaP, or dT vaccines)

Tetanus toxoid vaccine (may be given alone or as part of DTP, DTaP, or dT)

Component vaccines

Some vaccines are made by using only parts of the viruses or bacteria. These vaccines cannot cause disease, but they can stimulate

the body to produce an immune response that protects against infection with the whole germ. Four of the newest vaccines are made

this way. Examples of component vaccines:

1. Haemophilus influenzae type b (Hib) vaccine 2. Hepatitis A (Hep A) vaccine

3. Hepatitis B (Hep B) vaccine 4. Pneumoccocal conjugate vaccine

16

In Canada low income is associated with increased risk of all except;

a)low birth wt

b)infant mortality rate

c)varicella

d)fire death

e)social behavior problem.

Answer is C

It has been reported that the mortality rate for uranium miners is higher than that of the general

population. Before giving serious attention to this report, which one of the following questions would

you want answered first?

Was the comparison made with mortality rates for the entire general population?

Are uranium miners exposed to factors other than radiation which might increase their mortality

rate?

Is the numerator large enough?

What are the causes of death among uranium miners?

Have the two rates in question been standardized for age?

This is a difficult question because the “questions you would want answered first” is kind of subjective.

Generally when comparing mortality rates you would like to exclude the following alternative

explanations for any observed differences:

1. Confounding by age which could happen if the average miner is older than the average person in

the general population and would result in higher mortality rates among the miners simply

because they are older. Age standardization is then necessary before one could make valid

comparisons.

2. Statistical precision. If the mortality rate among the miners is based on 2 or 3 deaths (the

numerator in the mortality rate) then the difference may be due to chance. Suppose that there

are 100 miners and one died (due to any reason) then the mortality rate will be 1% which is

higher than general population mortality rate of let us say 1 per 1000. But because the first is

based on one death only, it is far from reliable. So you need reasonably large number of deaths

before you could make valid comparison.

I personally would choose [e] but can’t rule out [c].

A researcher tested a drug on people with vascular dementia. It reduced problems in behaviour. Then he used same drug for people with Alzheimer

and also produced a similar effect. Now he…?tests it or …This is called?

• Clinical trial 1

• Clinical trial 2

• Clinical trial 3

• Clinical trial 4

• Inventory therapy

There is not enough information to make a correct choice. The difference between phase 2 and phase 3 trials is that in phase 2 trial the drug is

given to a small group of patients to test its efficacy and safety. In phase 3 trials the new drug is compared with standard treatment to see if it

would do better. Phase 3 trials usually involve large number of patients and are often randomized and double-blind (neither the patient nor the

doctor knows what the patient is getting).

Phase 1 trials are small studies to test the safery of the drug usually on volunteers or patients with advanced disease. Phase 4 trials are studies done

to after the drug is marketed to detect any long term side effects.

17

. In designing a community prevention program, which one should be undertaken first?

a) Obtain guarantee of funding

b) Estimate the cost-benefit of intervention

c) Quantify objectives

d) Carry out a community needs assessment

e) Formulate possible strategies of screening

Example 26-1

A consumer group would like to evaluate the success of three different commercial weight loss programs. To do this, subjects are assigned to one of

three programs (Group A, Group B and Group C). The average weight of the subjects is not significantly different at the start of the study (Time 1).

Each group follows a different diet regimen. At time 1 and at the end of the 6 week study (Time 2); the subjects are weighed and their blood

pressure measurements are obtained. Examples of how statistical tests can be used to analyze the results of this study are given below.

1. t-test : Difference between the means of two samples.

a. Independent (Nonpaired) test: Tests the main difference in body weights of subjects in Group A and subjects in Group B at Time 1 (i.e. two

groups of subjects are sampled in one occasion)

b. Dependent (Paired test) : tests the mean difference in body weights of people in Group A at time 1 and time 2 (ie the same people are

sampled at 2 occasions)

2. Analysis of Variance: DIfference between the means of more than 2 samples

a. One Way analysis : Tests the mean difference in body weights of subjects in Group A, Group B and Group C at time 2 (ie one variable : group)

b. Two way analysis : tests the mean differences in body weights of men and women and in body weights if group A , Group b and Group C at

time 2 (i.e 2 variables: sex and group)

3. Correlation : The mutual relation between 2 continuous variables

tests the relation between blood pressure and body weight in all subjects at time 2.

4. Chi Square test: Differences between frequencies in a sample..

tests the difference among the percentage of subjects with body weight of 140lb or less in group A,B, and C at Time 2

Life expectancy is a comprehensive measure of

the health status of a population. This measure is

the age beyond which less than about 0.1% of

the original cohort of people live.

the usual amount of time a person in a

population can expect to live free of disease.

the maximum age that human beings as a species

could reach under optimum conditions.

the age where 50% or more of a population

cohort have died.

on the average, the expected number of years to

be lived by a cohort.

To estimate survival from a follow-up study,"time zero" must be defined precisely for each patient . this is best ensured

by

Let us work our way through this tough MCQ.

2. enrolling all patients on the same calendar date .

is obviously wrong as it is almost impossible to do that.

4. measuring from the time the disease is detected by a screening program .

This is also wrong. Using screen-determined zero time will tend to introduce lead time bias, i.e., cases detected by

screening will appear to live longer simply because they were detected earlier in their natural history.

5. selecting all patients of clinically comparable points in the course of the disease .

I excluded this option because it says “selecting”. We are not interested in selecting patients. Our aim is to define the

point in time from which to start “measuring” survival time. All the other options emphasize this “measuring”. So this is

an option designed to throw us off

We are left with 2 options:

1. "back dating" the entrance to the date of onset of the first symptoms , as obtained from the history

18

3. measuring from the first instance when each patient's symptoms met certain criteria for severity .

Both generally sound good. I thought that 3 is perhaps more objective. For instance, in a study of survival from lung

cancer it would be better to develop objective criteria for cough as initial symptom than to simply ask patients when

they started coughing. I am therefore inclined to go with option 3.

That is right. The immediate cause of death is by definition the one that immediately preceded death. (Which one would be obvious

form the context of the question.) Because this question was most likely about the underlying cause of death, it may not be possible

to determine the immediate cause of death from the information given.

. All of the following are responsibilities of

local public health units in Canada EXCEPT

health education.

immunization.

communicable disease control.

health promotion.

investigation of sudden death.

.1) From information recorded at school A it was

found that, out of a total of 400 missed 'person days'

during November, 100 were due to measles; 200 to

"flu"; and the rest to various other causes. At school

B in the same neighborhood, during the same period of

time, a total of 75 children were absent for 1 or more

days. Of these, 25 had suffered from measles, 25 from

"flu" and the rest from various other causes. It can

be concluded that

a)the overall morbidity rate was higher in school

A than in school B.

b)the incidence of "other causes" was greater in

school A than in school B.

c)none of the conclusions listed can be reached

with the data provided.

d)the incidence of measles was greater in school

B than in school A.

e)the incidence of "flu" was greater in school A

than in school B.

2)Over the last 40 years, expectation of life at

birth in Canada has improved steadily in both sexes.

The main reason for this overall increase in life

expectancy is

a)the trend toward lower fertility rates.

b)the average age of the population is increasing.

c)improvements in cause-specific mortality rates.

d)the decline in the infant mortality rate.

e)decreases in death rates at older ages.

3)Prevalance rate is 1/40000. then what is the prevalence of the disease

a. 1/40000

b.1/400

c.1/1000

4)It has been reported that the mortality rate

for uranium miners is higher than that of the general

population. Before giving serious attention to this

report, which one of the following questions would you

want answered first?

a)Was the comparison made with mortality rates for the entire general population?

b)Are uranium miners exposed to factors other than radiation which might increase their mortality rate?

19

c)Is the numerator large enough?

d)What are the causes of death among uranium miners?

e)Have the two rates in question been standardized for age?

5)decreased mortality rate of stroke is due to:

a) better control of blood pressure

b) regular use of aspirin

c) improvement of surgery process

6) Which of the following statements regarding perinatal mortality is

true?

A) the fetal mortality rate plus the number of fatalities among

live-born neonates within the first 6 days of life

B) the number of fatalities within the first 27 days of life

C) the number of abortions plus the fetal mortality rate (including

the number of fatalities within the first 6 months of life)

D) mortality occurs within the first year of life

7)The most frequently used indicator for the quality of life is:

A) the life expectancy rate at birth

B) the life expectancy rate without chronic disease and disability

C) the life expectancy rate at 60 years of age

D) the raw mortality rate

Reliable indicators of a quality-life include:

A) the amount of the gross domestic product

B) the unemployment rate

C) the raw mortality rate

D) crime statistics

E) leisure utilization statistics

9)According to 1990 data, which of the following causes resulted in

the highest mortality rate per 10,000 inhabitants in Hungary?

A) mortality due to hypertension

B) mortality due to ischemic heart disease (IHD)

C) mortality due to cerebrovascular diseases

D) mortality due to myocardial infarction

A 25-year-old Jehovah's Witness man is scheduled for emergency surgery following a motor vehicle accident in which he sustained

pelvic fractures. The patient is competent and lucid before the surgery and refuses the administration of blood products. Which

course of action is most appropriate in the event of significant intra-operative blood loss?

1) administration of packed red cells in the recovery

2) use of a cell saver

3) administration of hydroxyethyl starch (SM XX)

4) administration of packed cells after obtaining consent

5) intra-operative autologous blood donation

low effectivenss of pap smear is due to

a.high risk patient not screened

b. doctor cannot interpret the result effectively

c.low specificity of the test

20

cervical cancer is still high due to

high risk groups arent screened

increased incidence in past years

low specificity of pap smear

in studie of program on cohort of patient should be studied to provide accurate information on survival.cohort best assembled by

enrolling

a all patient e disease of interst and estimating the date of onset of 1.symptom

b all pat.on the same calender date

c pat.when try develop 1.complication of disease

d only pat compliance e treatment for their disease

e pat.at an early & uniform point in the course of their disease

a 58 year old patient was admitted to the hospital for appendicectomy. during the surgery his condition deteriorated and he passed

into coma. you started tube feeding. the patient has no family members or friends around and no advance directive. when can you

stop the tube feeding ?

1) you cannot stop it except by the order of court

2) you stop it according to the need of his bed for another patient

3) you cannot stop it because his condition was not serious

4) you can stop it according to the opinion of another physician

5) you consult CEO of the hospital to take a legal action

In a class of 25 students (15 male ,10 female)5 develop HA over 2 weeks period, during next 6 weeks add. 3 male and 2 f.

developed HA. Secondary attack rate of HA which one of the following?

20%

25 %

40%

50%

73%

The primary attack rate is just the incidence rate=No of all infections/population at risk =10/25. The incidence rate is called attack

rate when there is a dramatic and sudden increase in the occurrence of a disease (usually an infection). The secondary attack rate

(calculated as per doctorzeeek post) is a measure of the transmissibility/contagiousness of the infection ie the ability of the

infectious agent to spread from the index case to susceptible contacts. The formula for secondary attack rate (SAR) is

SAR (%)=(No of cases –No of initial cases) divided by (Total No in group- No of initial cases)

In this case SAR(%) = (10-5) / (25-5) = 5/20 = 25%

who is responsible for recalling faullty medical equipment

a_health canada

b_association of pharmaceuticals

c_health protection branch

d_medical equipment branch

e_royal college of physicians and surgeons

Health Canada

Hemochromatosis has a prevalence of 0.5% in the general population-----treatment of choice is regular phlebotomy. You decided

to initiate a new test for this disease. The literature : a sensitivity of 80.5% and a specificity of 89.5% for this test. You screen

1000 people ---institute treatment solely on the results of the test. Which one of the following is correct?

1) you will treat 40 people with phlebotomy

2) 995 people will not be treated

3) 100 people who do not have the disease will be treated with phlebotomy

4) 80% of the subjects will be correctly diagnosed

5) 200 people who have the disease will be denied treatment

21

0.5% have the disease so 0.5 X 1000 = 5 (true) cases and 995 are normal

If you then apply the reported sensitivity and specificity to these numbers, you will get the following table

Disease Total

Test Yes No

+ve 4 105 109

-ve 1 890 891

--------------------------------------------------------------------------------------------

Total 5 995 1000

From the table you could see that “(3) 100 people who do not have the disease will be treated with phlebotomy” is the closest to

the truth. All the other options do not fit the data.

All of the following are characteristics of provincial voluntary health organizations, EXCEPT

1) provincial governments contribute to their funding in proportion to the number of members. (XX)

2) they are governed by volunteers rather than by professionals.

3) they often carry out programs of education for the public, patients, their families, or health professionals.

4) they may provide direct services to patients.

5) they may conduct research or provide funds to others for research.