Polychoric correlation assumptions

[DavidB1]

I am performing a polychoric correlation to use in Principal Component Analysis.  The data are mostly Likert scale (4 levels), with a sample size of 68.  For some questions in the survey, there were only a few responses (1-4 out of 68) for certain numbers.  I know for Chi-Square tests (ordinal or otherwise), you have to combine some cells together first when that happens (if the expected value will be less than 5).  Do I also need to combine cells first for polychoric correlation?

[Ksharp]

Try PROC PRINQUAL 

[DavidB1]

Thanks.  My question is, do I need to worry that some cells only have a few values (like n=3 for "Strongly Agree") when I do polychoric correlation?  With Chi-Square Tests, you have to be careful that the expected value for any cell doesn't go below 5.  Does polychoric correlation have a similar requirement?