A Group of Graduate Students Conducted a Case-Control Study to Evaluate

question 154

Multiple Choice

A group of graduate students conducted a case-control study to evaluate the association between sporadic frontotemporal dementia and thyroid disease.  A total of 80 patients with sporadic frontotemporal dementia along with 160 age and sex surrogate informant matched controls participated in the study.  Results showed that thyroid disease was associated with frontotemporal dementia with an odds ratio of 2.5 and a 95% confidence interval: 0.9-7.9.  The students reported that patients with sporadic frontotemporal dementia were 2.5 times more likely to have thyroid disease compared to patients with no sporadic frontotemporal dementia.  They concluded that there is a statistically significant association between sporadic frontotemporal dementia and thyroid disease.  Based on this information, which of the following is the best evaluation of the students' conclusion?

• A)Correct because the confidence interval is wide
• B)Correct because the findings are clinically significant
• C)Correct because the odds ratio is greater than zero
• D)Incorrect because the authors did not perform a power calculation
• E)Incorrect because the findings are not statistically significant

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Definitions:

Range

The difference between the highest and lowest values in a dataset, providing a measure of spread.

Measurements

Quantitative data obtained by measuring objects or events using standard units.

Percentile

In statistics, this term refers to the threshold under which a specific percentage of data within a collection is observed.

Interquartile Range

The difference between the 75th and 25th percentiles of a dataset, representing the spread of the middle 50% of the data.