Study subjects included in this type of study do not show evidence of the disease under consideration when the study begins. The study subjects are classified by whether or not they have been exposed to the risk factor. The study subjects are observed forward in time to determine the number of new cases of the disease in those with and without exposure to the risk factor. This type of study is

A) Case-control

B) Cohort

C) Cross-sectional

D) Randomized controlled trial

This type of study identifies a group of people who have a diagnosed disease and a group of people who do not have this disease. Information is collected from medical records and other historical data about past exposure to a risk factor. This type of study is

A) Case-control

B) Cohort

C) Cross-sectional

D) Randomized controlled trial

In a study of the effectiveness of a new allergy medication, 100 people with seasonal allergies are recruited to participate in a study. At random, half of the subjects are given the new medication and half are given a placebo. Neither the subjects nor the clinical researchers know to which group the subjects have been assigned. What type of study is this?

A) Cross-sectional

B) Prospective cohort

C) Case-control

D) Randomized controlled trial

Which of the following is associated with a Case-control study?

A) It is prospective in direction.

B) It is useful for the investigation of rarely occurring diseases.

C) It is useful for the investigation of rarely occurring risk factor exposure.

D) None of the above.

Randomization is used in a clinical trial to

A) ensure that all trial subjects have an equal chance of being assigned to the experimental or control groups.

B) distinguish the clinical trial from a cohort study.

C) distinguish the clinical trial from a Case-control study.

D) ensure that the experimental and control groups are selected from the same population.

In a randomized controlled trial, the research subjects should be from a variety of backgrounds and exposures so that they accurately represent the broader population.

A) True

B) False

A researcher is interested in the cause of neonatal jaundice. To study this condition, he selects one hundred children who were diagnosed with neonatal jaundice. He also selects another one hundred children born during the same time period at the same hospital who did not have a diagnosis of neonatal jaundice. He then reviewed the obstetrical and delivery records of their mothers to determine if there were any prenatal or perinatal exposures to risk factors.

Which study design was used in this study?

A) Cross-sectional

B) Prospective cohort

C) Case-control

D) Randomized controlled trial

In 1965 one thousand men were working in an asbestos manufacturing facility. The incidence rate of lung cancer in these men up to the year 1995 was compared with that of one thousand men who began work as telephone repairmen in 1965. Twenty of the asbestos factory workers and four of the telephone repairmen developed lung cancer during the thirty years between 1965 and 1995.

This study compares the incidence of lung cancer between an exposed group and an unexposed group.What type of study is this?

A) Cross-sectional

B) Prospective cohort

C) Case-control

D) Randomized controlled trial

A group of women attending a clinic for their first prenatal visit are enrolled in a study to determine if taking erythromycin during pregnancy adversely affects birth weight. The women are randomly put into control or experimental groups.

Which study design was used in this study?

A) Cross-sectional

B) Prospective cohort

C) Case-control

D) Randomized controlled trial

A study is done to review and understand the influence of environmental risk factors for blood lead concentrations in children. Blood specimens are taken from a selected subgroup of the children who have been identified to be high risk because they live in an inner city and are poor. At the time that the blood specimens are taken, the mothers are asked about several possible environmental exposures.

What type of study is this?

A) Cross-sectional

B) Prospective cohort

C) Case-control

D) Randomized controlled trial

In 1997 five hundred men who work at a local chemical manufacturing facility were examined for coronary artery disease. The men have been examined every three years to identify new cases of coronary artery disease.

A) Cross-sectional

B) Prospective cohort

C) Case-control

D) Randomized controlled trial

A number of studies have shown a relationship between obesity or body mass index (BMI) and endometrial cancer.Weiderpass and colleagues (2000) conducted a population-based case-control study in Sweden among post-menopausal women aged 50-74.The following table shows the association between obesity and endometrial cancer in the Weiderpass et al study. [Source:Fleming Cases and Concepts]

CasesControls

Obese205350

Nonobese3872,171

Total5922,521

Calculate and interpret the odds ratio and choose from the answers below

A) 3.3; Obese women have greater odds of developing endometrial cancer than nonobese women

B) 3.0; Obese women have lesser odds of developing endometrial cancer than nonobese women

C) 3.1; Obese women have lesser odds of developing endometrial cancer than nonobese women

D) 3.2; Obese women have greater odds of developing endometrial cancer than nonobese women