Question

In 1978, the National Institute for Occupational Safety and Health (NIOSH) undertook a study of 25,000, civilian employees of the Quincy Naval Shipyard. The cohort consisted of white males who worked at the shipyard from 1952-1977 who were identified from health records from the shipyard's health center. Review of records revealed that 1,000 cancers occurred during this period. Beginning in 1978, the 18,000 study members that were still alive and could be located were mailed annual questionnaires. This follow-up will continue until 2010. What kind of cohort study is this? Retrospective Prospective Ambidirectional

Answer 1

Answer ; Retrospective study.

Reason ; In the given study statement, it is revealed that the study is about the employee of the naval shipyard who were working in certain time period and experienced cancer among them. And the study continues until 2010. From the given data it is known that the study is mostly focused on the past data and the current situation. The only cohort study which enhance this type of case are above mentioned type of study. Other types of study are not reliable for this presented case.