I am new to this forum and would greatly appreciate your help. I know how to do a t-test for significance when I have simple sets of raw data. Now, however, I have to do it on already "processed" data, and in a more difficult way (at least for me).

What I have is the following: I have two sets of measurements of a parameter over time. For each time point, data from around 20 individual measurements were taken and processed to obtain the mean and the standard deviation; of course I also know the number of samples for each data point.

I would like to know how to perform a kind of t-test and how to calculate p-values to tell me whether the two sets of data ("curves" when plotted) are significantly different. In principle I think it should be possible to perform a t-test on the two data points (for which I have the mean, the SD and the sample size) for each time point.

But

(1) I don't know how to do a t-test on processed data, and

(2) I don't know how to get a (kind of) p-value for the two data sets over time, to show whether they are significantly different.

Could anybody help me with this problem?