Will a mistake in my data collection for my thesis effect my whole grade? I am currently doing my undergraduate thesis for psychology. I noticed in my data collection when asking the participants age i asked it wrong e.g. 18-21,21-25. Age is not one of my variables i am testing in this study and will have no implication on the results of my study. If i acknowledge this as a limitation and state how it wont impact results will this still have a big impact on my grade?
If age is not a variable used in the later analysis, then it cannot be wrong.

If you should have included age in the later analysis, then that may cost some points - depends on what they are looking for...

Including age in the original survey is usually a good thing as it means that that data may be suitable for different variations of studies ie the data is possibly more useful.