Question

design 3 cohort studies: one prospective cohort study, one retrospective cohort study, one ambidirectional cohort study using the example smoking and lung cancer and identify the following 1) research qestion, 2) exposure, 3) outcome, 4) the placement of the researcher ( is the researcher beginning the study after the participants have developed symptoms or a disease? ; is the researcher starting the study when participants are first exposed?

Answer 1

Desiqn 1:

Prospective cohort study : The study involves taking a cohort of subjects and watching them over a long period

(1)

Research qestion, :

Does smoking for a long period cause increase in affected by lung cancer?

(2)

Exposure:

Randomly assign the participats two mutually exclusive groups. Experimental Group: Smokers. Control Group: Non-Smokers. Studythe participants over a log period of time and note down who are affected by lung cancer.

In this experimentation:

Exposure is Smoking

(3)

In this experimetation,

Outcome is: Getting affected by lung cancer

(4)

the placement of the researcher :

The researcher is starting the study when participants are first exposed

Desiqn 2:

Retrospective cohort study : The study involves collecting data from records and from participants regarding their smoking status and whether they are affected by lung cancer.

(1)

Research qestion, :

Has the action of smoking for a long period caused increase in affected by lung cancer?

(2)

Exposure:

In this experimentation:

Exposure is Smoking

(3)

In this experimetation,

Outcome is : Getting affected by lung cancer

(4)

the placement of the researcher :

The researcher is beginning the study after the participants have developed symptoms or a disease

Desiqn 3:

Ambidirectional cohort study : The study involves both retorspective and prospective phases of study.

(1)

Research qestion, :

Is the action of smoking for a long period causing increase in affected by lung cancer?

(2)

Exposure:

In this experimentation:

Exposure is Smoking

(3)

In this experimetation,

Outcome is : Getting affected by lung cancer

(4)

the placement of the researcher :

The researcher is starting the study when participants are first exposed

Explanation: The placement of the resarcher in Ambidirectional cohort study is: At the end of the Retrospective part and the beginning of the Prospective part.