I got some groups to compare. My variabels are in the physical fitness area so BMI, bodyfat etc... I have 4 groups, categorized in gender and two school classes from 2010 and 2012 (Men2010 Men2011, Women2010 and Women 2012). I have used box plots to work them all in one figure for each variable. Box plots was used due to none of the groups were normally distributed for any variable, and therefore mean was not an accurate form for central trend. Box plot uses median which is usable if the data is not normally distributed.
What test do I run for checking for signifigance (p-value)?
Sorry for any spelling mistaking and the messy way I lay it all out. Thankful for any help!