Biostadistics

Question 1

Intention to treat analysis

Answer 1

subject results are analyzed according to the group that they were initially assigned to (not according to adherence) is one technique used to analyze outcome data and preserve randomization

Question 2

When the cut-off point of a test is decreased, what happen with specificity and sensitivity?

Answer 2

Decrease in specificity (TN/(TN+FP)) and an increase in sensitivity (TP/(TP+FN)).
To identify more patients (usually in the form of decreasing the cutoff value) but with more false positives occurring.

Question 3

p-value of 0.052 meaning in a study that compares two medications?

Answer 3

There is a 5.2% chance that A is more effective than B is due to chance.

Question 4

If the cutoff value of a diagnostic test is increased (meaning it takes more of a finding to suggest a diagnosis), what should we say about specificity and sensitivity?

Answer 4

The sensitivity decreases while the specificity increases.