There are 4 experiments, each individual experiment is repeated such that there are 3 measurements to make an average -> should end up with 4 average values, one for each experiment. The aim is to measure activity from a radionuclide added to biological cells and to see whether adding a particular compound affects the uptake of the radionuclide.
The first experiment is a control, so just add the radionuclide to the cells, measure the activity, repeat with new cells until 3 measurements are made, calculate the average etc etc. The second experiment includes adding the compound to the cells, under the same environmental conditions as experiment 1 and as before to find the average value.
The 3rd experiment has different environmental conditions without the added compound to the cells, measure activity 3 times. Then for the 4th experiment, add the compound under the conditions for the 3rd experiment, then measure activity 3 times.
So, there will be 4 average values - I have to determine whether there is a statistically significant difference between the experiments. I originally thought to do a student's t-test, but I was informed that is wrong. Sadly, statistics is my weak point so I would greatly appreciate any help on the matter, which statistics test would be best? And, how do you decide where there is a cut off between a significant difference and no evidence for any difference?