Yes. Or you could use analysis of covariance, with group as factor1. Does linear regression allow me two compare the three groups when one group has only 17 individuals?

and the several covariates.

There is no assumption that both groups have to be > 30 in a t-test.Am i right in that it is the t-test assumptions that applies here, and that the smallest group is too small for comparison, since it has only 17 individuals which is less than 30?

Many people hate rules of thumb, but if you have at leastDo I have to worry about how many coviartes i include in the adjusted analysis when N is so small

20 observations per predictor, then IMHO you should not be

worried too much.

With kind regards

K.