Can I compare two sets of data (with some overlapping items) using a t-test?

I don't know if I'm doing this right. Basically I've taken six measurements and each measure is rated by 5 people. This gives me 30 scores of which 10 are correct and 20 are incorrect. I want to see if the 10 measurements in the correct group are significantly different from the 20 measurements in the incorrect group. The problem, however, is that since really I only have six different values for the measurements, there are overlapping values in each group. What I ended up doing was running a t-test with H0 being correct=incorrect. I keep thinking something there is wrong...