Guide on calculating Test Parameter, P value, Mean Difference


Hi, I'm wondering how some of the above was calculated.

Two different groups looked at are short stay n 58 and long stay n 42
I am wondering how the last two columns were calculated. In particular test statistics, p value and mean difference with intervals

If we take the first row 'age'
two sample t df = n1 + n2 -2
98 = 58 + 42 -2

From there I am having difficulty seeing how 0.3 0.76 and 0.5 ( -3.0 to 4.1) were all calculated.