I need anyone who understands these things to help with interpretation of an output from minitab please.

I am looking at whether results for a test (INR) from a handheld device are statistically different from a result from the same patient processed at a nationally accredited lab.

Two-Sample T-Test and CI: Lab INR, POCT INR

Two-sample T for Lab INR vs POCT INR

_ _ _ _ __ N __ Mean _ StDev _ SE Mean

Lab INR __ 58 _ 2.576 _ 0.785 __ 0.10

POCT INR_ 58 _ 2.429 _ 0.831 __ 0.11

(Underscores added to format the HTML better)

Difference = mu (Lab INR) - mu (POCT INR)

Estimate for difference: 0.146552

95% CI for difference: (-0.150828, 0.443931)

T-Test of difference = 0 (vs not =): T-Value = 0.98 P-Value = 0.331 DF = 113

I understand it satisfactorily up to the interpretation of the P-value.

Do I say that my null hypothesis (handheld gives same result as lab) is not rejected because the P-Value is within the range of the 95% Confidence Intervals?

Or do I reject the null hypothesis because the P-value is greater than my alpha of 0.05?

Thanks for any help

Ben Quinn.