Table 2.
Validation of different methods of identifying a long term care (LTC) nursing home stay using Medicare and MDS data, vs. data in Medicaid as the gold standard, in patients dually eligible for Medicare and Medicaid
| Method | LTC nursing home length of stay in Medicaid data | |
|---|---|---|
| Cut offa Length of stay >30 days | Cut offa Length of stay >100 days | |
| N = 84,869 | N = 53,837 | |
| 1) Part A and B with E&M Charge for NH Services | ||
| Sensitivity | 89.68% | 92.55% |
| PPVb | 66.45%b | |
| 2) Part A with MDS episode of care | ||
| Sensitivity | 93.96% | 93.09% |
| PPV | 91.60% | 84.65% |
| 3) CMS Method: MDS alone | ||
| Sensitivity | 77.49% | 93.64% |
| PPVb | 78.71%b | |
E&M evaluation and management, NH nursing home, PPV positive predictive value, MDS Minimum Data Set, CMS Centers for Medicare and Medicaid Services
aFor cut off of > 30 or >100 day lengths of stay, the Medicaid data demonstrated > 30, and > 100 day length of stay in the validation
bOnly one PPV could be detected for the different lengths of stay in methods one and three. Method one relies on provider charges to identify nursing home stays, and length of stay cannot be reliably estimated. Method three uses any length of stay in a nursing facility (whether skilled nursing facility or LTC) > 100 days as the criterion