Cohort Study

Data
Collection

Step 5: Data Collection

Now that you have defined the appropriate variables and determined the information you want to collect, you are ready to determine exactly how you are going to collect your data. You need to collect information on the exposure variable and information on the outcome variable.

5.	What is the best source for gathering information on the exposure variable? [See Gordis, Ch.3, pg. 37; Ch.18, pg. 283-285]
		a.	Collect information from the human resources department on all employees and their job categories as of September 1st, 2002
		b.	Assess baseline exposure at the beginning of the study period (September 1st, 2000)
		c.	Collect monthly updated files in the human resources department, beginning with the start of the study through the end of the study

6.	What is the best source for gathering information on the outcome variable? [See Gordis, Ch.3, pg. 35-36]
		a.	diagnosis of Susser Syndrome identified from the hospital charts of the local hospital and based on the neurology consultation and supported by lab results
		b.	complaints of neurological symptoms identified from the records of the employee health clinic
		c.	complaints of neurological symptoms based on information provided by the human resources department about medical leave of absence

7.	What is the best source for gathering information on the outcome variable? [See Gordis, Ch.3, pg. 35-36]
		a.	look through the records of the local hospital dated from September, 2000 to September, 2002 to identify those with disorder and see if there is information in the chart about their employment
		b.	link a computer database containing cohort members from Glop Industries with the discharge database from the local hospital

Your supervisor reads over your recommendations and decides to send out two teams of investigators - one to Glop Industries and the other team to the hospital. However, before the teams can leave and the data can be collected, your supervisor instructs you of all the administrative work that must be in order. You need to:

Get approval of your study from your Institutional Review Board (IRB) - this will ensure that the study adheres to the ethical principles of conducting public health research and that the rights of study participants are protected.
Prepare a budget and get funding.
Develop an operations manual to be used by all study personnel which will describe the standardized procedures for collecting data, managing data, etc. This is used to ensure quality control.
Design a consent form for study participants - it should clearly indicate your goals; it should also explain risks, benefits and expenses that participants might incur if they decide to participate in your study; it should also state how participants would benefit from their participation and how you plan to make use of the data once it is collected.
Design a questionnaire that will be used to collect data from the study participants.
Hire and train data extractors.
Design a data management plan (how and where paper forms will be stored, when and how they will be entered into computer database, when periodical checks of the data will be performed to spot possible problems in the study).
Design a data analysis plan and think about publicizing your findings.

Having received the necessary IRB approval, designed the consent form, and planned out all of the logistics, the teams are deployed. The data begin to file back to the Department of Health and must now be collated and carefully entered into the computer database. Despite your leadership role, you are still the intern and thus have the humble yet crucial responsibility of data entry. Once all of the data are entered, you can proceed to the analysis stage where the association stated in your hypothesis is characterized and tested.

Learning
Objectives

Introduction
to Study

Data
Collection