I need the REGION variable to have the 9 regional divisions (i.e. South Atlantic) for an analysis where I merge external policy data. The 9 divisions are available in the NHIS, but do not seem to be so for the IHIS (e.g. only West, South, etc.). Is the 9-level version only available for certain years, or are they coded differently in the IHIS from what the codebook suggests?
Thank you for your help.