Analysis of the California In-Home Supportive Services (IHSS) Plus Waiver Demonstration Program. Outcome Measures


Medicaid claims-records are also used to identify the occurrence of selected events (e.g., ER, hospital stay, nursing home placement) and to compile expenditures. These are used as the program evaluation’s primary outcome measures. As shown below, a number of specific services were identified in the claims data. A further refinement involves the convention of identifying hospital stays where an ambulatory care sensitive condition (ACSC) is a primary or secondary diagnosis. Hospitalizations with one of these diagnoses are said to be indicative of a potentially “avoidable” hospital stay, and indicative of the quality or performance of primary health care (Billings, Zeitel, Lukomnik, et al., 1993). While there is some overlap in ACSC classifications for children and adults, there are separate standardized algorithms for each of these age groups (AHRQ, 2007a, 2007b).19

Following is a brief description of the claims-based items compiled for 2005. Both expenditures and service use rates are adjusted by the number of IHSS eligibility days in the study year.20

  • Member of managed care Medi-Cal in 2005. This measured is used to omit cases from analyses involving claims-based items.

  • Total Medi-Cal Expenditures 2005, adjusted for IHSS eligible months in period. We limited these data to non-pharmacy-related expenditures.

  • Medicaid expenditures use HCBS waivers in combination with State Plan optional personal care benefit in 2005.

  • IHSS expenditures (separate from the above) in 2005.

  • Hospital use in 2005; total hospital Medicaid expenditures; repeated for ACSC admissions.

  • Nursing home use in 2005; total Medicaid expenditures, and use.

  • Home health use in 2005; total Medicaid expenditures.

  • Medical provider and other outpatient services in 2005; total Medicaid expenditures.

  • ER use in 2005.

  1. Table D-4 and Table D-5 in Appendix D show the conditions used to identify ACSC outcomes.

  2. The original work plan also included the generation of Medicaid claims data for 2004. This information was compiled, but as the analyses reported are largely focused on comparisons of IHSS continuing from 2004 and new IHSS recipients in 2005, we have limited the presentation of data to 2005, differentiating new recipients. Payments via other state programs, and non-state sources are not represented. For example, expenses reimbursed by Medicare will under report total use and expenditures as some claims are reimbursed solely by this non-Medicaid source or for which Medicaid payment is limited to co-payments and deductibles. These limitations primary concern the expenditures for recipients who are dually eligible for Medicare and Medicaid. Service events, such as a hospital stay, usually have at least a Medicaid co-payment, and can be identified. Data on Medi-Cal eligible months in the period was not available to the project, but we do have months of IHSS eligibility.

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