I selected 30 respondents for focus group interview. Now I wish to know reliability of the raters ( Respondents). Please suggest me qualitative and quantitative methods for testing reliability of respondents of focus group interview.
First, qualitative research seldom concerns it self with reliability, which is primarily a quantitative criterion for data quality.
Second, I have extensive experience with focus groups and I do no have the slightest idea how you would establish the reliability of the individual participants. In particular, it its seldom the case that every participant gives a detailed answer to every question. Often, participants simply nod their approval as others put forth ideas that they share. So, if you don't have complete data on every participants for every question, the whole concept of reliability is dubious at best.
As an alternative to reliability, Lincoln and Guba (1985) suggest dependability, which you might consider in terms of the extent to which the discussions in each focus group tended to cover the same ideas.