A Cohort of Patients with Myotonic Dystrophy Was Retrospectively Analyzed

question 337

Multiple Choice

A cohort of patients with myotonic dystrophy was retrospectively analyzed from 1993 to 2010 to identify incident cases of cancer.  The researchers identified 2 cases of thyroid cancer and reported a standardized incidence ratio of 7.4 (P-value = 0.02) .  This ratio was derived using which of the following formulas?

• A)Expected number of cases divided by the population at risk
• B)Observed incidence of cancer minus expected incidence of cancer
• C)Observed number of cases divided by expected number of cases
• D)Observed number of cases divided by population at risk
• E)Observed number of cases plus projected number of cases

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Definitions:

Predictive Validity

The extent to which a score on a test or measurement accurately predicts future performance on a related task or behavior.

Concurrent Validity

The degree to which the results of a particular test or measurement correspond to those of a previously established measurement for the same construct.

Content Validity

The extent to which a test measures all aspects of the concept or construct it intends to assess, ensuring that the test is fully representative.

Mental Status Exam

A structured assessment of a patient's level of cognitive function, emotional state, and other areas of mental health, often used in psychiatric evaluations.