asked on

Assessing the reliability of a repeated measures (within group) continuous variable

Hi Folks,

I have a 10 item construct with each item measures on a 7 point Lickert scale. The construct is measured at two points in time - a repeated measure. I can run a Cronbach alpha for each seperately and I can combine the variables and run an alpha for the combination but there is dependence here so these aren't correct approaches - so how do I assess the reliability of a repeated measures construct like this?

ASKER CERTIFIED SOLUTION

richdiesal

membership

This solution is only available to members.

To access this solution, you must be a member of Experts Exchange.

Start Free Trial

freeversed

ASKER

The scale is the same, implemented twice - a single reliability estimate seems logical. Is there a valid way of assessing the reliability of the scale taking into account that it is a repeated measure?

Otherwise, I guess the first instance is the only valid one for reliability analysis.

SOLUTION

richdiesal

membership

This solution is only available to members.

To access this solution, you must be a member of Experts Exchange.

Start Free Trial

freeversed

ASKER

In this situation the solution is to report the reliability of the first instance only because there is dependence for the second.

freeversed

ASKER

In this situation the solution is to report the reliability of the first instance only because there is dependence for the second.

richdiesal

That depends on the specifics of what you're doing. I'd strongly recommend giving more information about your measurement model the next time you post a question on this topic.

In many models, a researcher needs to model that dependence as part of their reliability estimate. Using only the first instance in those cases is incorrect.