# What statistical test to use? (SPSS)

#### cityofstats

##### New Member
Hello,

So I had to conduct an experiment for my university assignment and now I need to carry out a statistical analysis. The experiment was to execute jump diagnostics under different conditions. The performed test included a counter-movement jump with closed eyes. A closed-eyes condition had to be compared to a standardized counter-movement jump. 3 standardized jumps were performed with 30 sec rest in between and after a short break 3 counter-movement jumps with closed eyes were performed as well. The group consisted of 12 participants. The group members remained the same throughout all jumps. I have to use Kinovea software for jump analysis.

The research question I aim to investigate is (the question hasn't been finalised yet): The effect of visual impairment on jump performance in comparison to a standardized counter-movement jump (eyes open).

So, we have one group of participants and 3 jumps executed one after another (30 sec rest intervals). Would I be right to say that I need to conduct a repeated measures ANOVA test? One group; jump 1; jump 2; jump 3. (attached you can find an example).

I' ve been thinking to analyse knee angles and then jump because jump heigh is affected by knee angles. However, the main influencing factor here is visual impairment, therefore, I'm not sure whether I should analyse 2 parameters? My tutor told me that analysing 1 parameter isn't sufficient but I'm struggling to conceive how I can analyse 2 parameters plus a condition that affect them.

Anyway, am I right saying that repeated measures ANOVA is the test that I should use?

#### Karabiner

##### TS Contributor
You have 2 repeated-measures factors "blindness" (2 levels, blinded versus not blinded) and "jump
order" (#1, #2, #3), therefore 2x3=6 conditions (= 6 columns in your spreadsheet).

Did you randomize the order of conditions, so that 6 particpants performed unblinded jumps first, and
the other 6 performed blindend jumps first? Otherwise, condition effects will be confounded with
sequence effects.

With kind regards

Karabiner

#### cityofstats

##### New Member
You have 2 repeated-measures factors "blindness" (2 levels, blinded versus not blinded) and "jump
order" (#1, #2, #3), therefore 2x3=6 conditions (= 6 columns in your spreadsheet).

Did you randomize the order of conditions, so that 6 particpants performed unblinded jumps first, and
the other 6 performed blindend jumps first? Otherwise, condition effects will be confounded with
sequence effects.

With kind regards

Karabiner
Hi, thanks for your answer. Each participant performed one jump at a time. It means participant 1 performed 3 unblinded jumps first (30sec rest between jumps) and then the same participant performed 3 blinded jumps. Then, the participant no.2 followed the same procedure, particpant 3, participant 4 etc.

So, it's still a repeated measures ANOVA test if I understood correctly?

#### cityofstats

##### New Member
I got a bit confused. Should this be a TWO-WAY repeated measures ANOVA or ONE-WAY repeated measures ANOVA?

#### Karabiner

##### TS Contributor
You have 2 repeated-measures factors "blindness" (2 levels, blinded versus not blinded) and "jump
order" (#1, #2, #3)