# Cell count-which test to choose when comparing two groups to a control?

#### cos85

##### New Member
Hello dear members of the Talkstats forum,

In my research we counted algae cells with the counting chamber.N=8.We have the means of these three groups : the control and two other settings involving ultrasound probe 1 and ultrasound probe 2.
We wanted to see if, during a certain period, the ultrasound probe 1 or 2 increase or decease the cell count compared to the control.What would be here the best test for significance?

I have some concerns :The data is not normally distributed, but isnt that because of the low n number? I dont know if the data is parametric or non-parametric.On the one side is parametric because is measuring of growth and on the other hand is non parametric because we counted the dividing cells with 2 and the experiment was also about stress response of a living being.Does this make sense?
I
I would guess a non-parametric test but then i still don`t know how to choose between two way non-parametric anova, one way anova Kruskal-Wallis... Do i need to test each date ? .Does anybody have any feedback? Thnx!

Last edited: