The 2007 Provider of Service (POS) data were used to examine the distribution of post-acute providers nationally. This included looking at the number of freestanding versus hospital-based SNFs, IRFs, HHAs, and freestanding versus HwH LTCHs in each state.11 These analyses also looked at the distribution of types of colocated providers across the United States. The purpose of this analysis was to understand the distribution of types of providers in different geographic areas of the country. For example, LTCHs are not available in every state and freestanding IRFs are not common in many areas of the country. This supply table shows the variation of supply and helps in interpreting observed differences in utilization of services by geographic area.
Bed supply variables were also created for the multivariate regression models using the 2007 POS data. These variables measured the number of LTCH, IRF, and SNF beds per 1,000 Medicare beneficiaries in each state. These bed supply variables were used in the multivariate analyses to contribute to an understanding of acute index admission length of stay, the likelihood of any PAC utilization, the first setting of PAC for beneficiaries discharged to PAC, and episode payments and acute hospital readmissions. By including the supply variables in the multivariate models it is possible to examine the magnitude of the effect of supply of PAC services on utilization.