biostatistics questions

QUESTION 1

The margin of error is always greater than or equal to the standard error.

True

False

3.4 points

QUESTION 2

A clinical trial is being conducted in order to determine the efficacy of a new drug used to treat Rheumatoid arthritis. The efficacy of the medication will not only be determined by the physical improvement of symptoms but also by using a blood test to examine the concentration C-reactive protein (an inflammatory marker) in an individual’s blood. If the researcher wants a margin of error for the level of C-reactive protein to be less than or equal to 3.0 mg/dL, and if the standard deviation for C-reactive protein concentrations among arthritis patients was previously documented at 8 mg/dL, how many patients should be recruited for each group in the study assuming a 95% confidence interval will be used to quantify the mean differences between the control group and the treatment group?

n
for the treatment group = 112; n for the control group = 111

n
for the treatment group = 56; n for the control group = 57

n
for the treatment group = 55; n for the control group = 55

n
for the treatment group = 112; n for the control group = 112

3.4 points

QUESTION 3

It is important for researchers to account for attrition or loss of participants during follow-up.

True

False

3.4 points

QUESTION 4

When performing a Mann-Whitney U test, one should always use the higher value of the calculated U values to compare to the critical U value while making the decision rule.

True

False