In the Paper [Gold E,Gordis L,Tonascia J,et Al

question 9

Multiple Choice

In the paper [Gold E,Gordis L,Tonascia J,et al.Risk factors for brain tumors in children.Am J Epidemiol.1979;109(3) :309-319],investigators conducted a case-control study to identify risk factors for brain tumors in children.Children with brain tumors were compared with two groups of controls: The first control group,called normal controls,consisted of children with no known malignant disease.The second control group,called cancer controls,consisted of children with malignancies other than brain tumors.What is the benefit of using multiple controls in case-control studies?

• A) This may reduce the recall bias from participants.
• B) This may reduce the selection bias for participation.
• C) This may reduce the potential confounders from investigators.
• D) This may reduce the placebo effect from participants.
• E) None of above.

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Definitions:

Precautionary Demand

The desire to hold cash or liquid assets as a safeguard against potential financial emergencies.

Speculative Demand

The demand for assets or goods not for their immediate consumption or use, but for the purpose of resale at a higher price in the future.

Transaction Demand

The demand for money as a medium of exchange, influenced by the level of economic activity.

Branch Banking

The operation of a banking service through multiple branches located in different areas, offering a wide range of services to customers across locations.