Dear Alan

You have to see the scale of measurement. If it is not ratio scale, you should go for non-parametric test fro comparison, otherwise you may opt for parametric test depending upon the fulfillment of assumptions.

Regards

Dear Alan,

A good place to start would be two scale variables measuring your two constructs. You could then create a scatter plot and decide whether to use a parametric or a nonparametric correlation. Have a look at my study guide for more information:

https://www.researchgate.net/publication/274635640_Pearson_Correlation

Technical Report Pearson Correlation

Thanks. Do I then compare that with the third variable?

 Thanks! Are mixed methods valuable for surveys?

Hello Alan,

I am responding primarily to your most recent question:

It all depends on what you mean by "mixed methods".  By these words, many people assume that the distinction between methods refers to what are traditionally referred to as qualitative methods versus quantitative methods.

Given that your original question indicated that you were interested in analysing your data statistically, that essentially rules out qualitative methods.

In essence, if you use surveys / instruments that yield only quantitative data (numbers), as does the ProQOL, you have ruled out using mixed methods in the traditional sense. (i.e., you have ruled out qualitative methods.) However, it depends on what you mean by "methods".  There are different methods within the quantitative bundle.  Up above, Peter has referred to correlations.  They are related to other things such as regression analyses.  But there are other quantitative "methods" such as tests that assess differences. These include t-tests and ANOVAs. 

Much depends on what your surveys are like in terms of the methods you can use with them. Perhaps some of your surveys yield data (usually verbal responses) that permit qualitative analyses. However, even verbal data can be analysed in ways that are primarily quantitative - and that therefore permit subsequent statistical analyses.

Apart from that, ultimately, a lot depends on what your research questions are.  For example, are you wanting to make comparisons between the scales, or are you wanting to make comparisons between groups within your research based on their results on each of the scales?  These are slightly different focuses.

Robert.