It Has Been Suggested That Occupational Exposure to Benzene in the Petroleum

question 11

Multiple Choice

It has been suggested that occupational exposure to benzene in the petroleum industry increases the risk of developing leukemia. The levels of benzene to which workers in this industry have been exposed were high from 1940 to 1970, but since 1970 have been significantly reduced.
What kind of study design, using petroleum workers, would provide the most useful information on whether benzene affects incidence rates of leukemia in this industry? (You may assume that records of individual worker assignments to jobs involving benzene exposure have been maintained by the industry.)

• A) Experimental
• B) Retrospective cohort
• C) Prospective cohort
• D) Case-control
• E) Cross-sectional

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Definitions:

Recombinant DNA Technology

Techniques used to join together DNA molecules from two or more different sources and insert them into a host organism to produce new genetic combinations.

Short Tandem Repeat

Sequences of DNA where a pattern of two or more nucleotides is repeated and the sequences are directly adjacent to each other.

Gene Therapy

A medical technique that modifies a person's genes to treat or prevent disease.

Ex Vivo

A process or experiment conducted on tissues from a living organism in an external environment with minimal alteration.