SPM – MCQ 104 – Z score calculation

The Hb level in healthy women has mean 13.5 g/dl and standard deviation 1.5 g/dl, what is the Z score for a woman with Hb level 15.0 g/dl:
A. 9.0
B. 10.0
C. 2.0
D. 1.0

Correct answer : D. 1.0

The value (15g/dl) lies 1 SD (1.5g/dl) above the mean of 13.5g/dl. Hence the Z score is 1.