To analyze health care utilization patterns, we created indicators of the probability and level of service use. In general, we used definitions developed as part of the Health Plan Employer Data & Information Set (NCQA 1998). Our goal was to create a parsimonious set of measures, while still capturing the range of variation within and among groups. Table II.5 lists the measures, the SMRF source file, and the method used to construct each measure.
Where possible, we included state-specific procedure codes to classify emergency room, preventive, and mental health/substance abuse services. These codes were obtained from internal files as well as from follow-up discussions with states.
Separate utilization measures were constructed for mental health and substance abuse services. As discussed earlier, Florida's outpatient SMRF file did not contain any diagnostic data. As a result, we were unable to distinguish between mental health and substance abuse services in Florida; we therefore decided to combine these services into a broader measure reflecting behavioral healthcare.
|SMRF Source File||Comments|
|Percent with a hospital stay||Inpatient||Number of children with one or more hospital stays; excludes maternity stays, newborn stays, mental health/substance abuse-related stays, and those with same-day stays (no overnight)|
|Percent with an outpatient provider visit||Other||Number of children with one or more outpatient provider visits; includes visits with following types of service: physician, other practitioners, outpatient hospital, family planning, clinic, EPSDT, rural health clinic; excludes visits with place of service inpatient or nursing home; excludes emergency room visits|
|Percent with an emergency room visit||Inpatient and other||Number of children with one or more emergency room visits; includes visits with CPT-4 or state-specific service code signifying emergency room (ER) visit AND place of service = outpatient, clinic, or ER.|
|Percent with a preventive visit||Other||Number of children with one or more preventive visits; includes visits with type of service = EPSDT, with primary/secondary diagnoses of V20-20.2, V70.0, V70.3-V70.9, or with state-specific procedure codes signifying preventive visit; excludes visits with place of service = inpatient, with mental health/substance abuse service code, or with emergency room service code|
|Percent with a dental visit||Other||Number of children (over age 3) with one or more dental visits; includes visits with type of service dental, or procedure codes Y2020 or Y2030|
|Percent with a prescribed drug||Person summary file||Number of children with one or more prescribed drug claims (type of service = prescribed drugs)|
|Utilization Intensity Measures|
|Hospital days per 1,000 children||Inpatient||Number of hospital days divided by number of children(a) and multiplied by 1,000|
|Outpatient provider visits per 1,000 children||Other||Number of outpatient provider visits divided by number of children and multiplied by 1,000|
|Emergency room visits per 1,000 children||Inpatient and other||Number of emergency room visits divided by number of children and multiplied by 1,000|
|Dental visits per 1,000 children||Other||Number of dental visits divided by number of children and multiplied by 1,000|
|Mental Health/Substance Abuse Treatment Measures|
|Percent with any mental health/substance abuse treatment||Inpatient, other, long-term care||Percent with any inpatient or outpatient treatment (as defined below)|
|Percent with any outpatient mental health/substance abuse treatment||Other||Number of children with mental health/substance abuse treatment in outpatient setting; includes services with CPT-4 or state-specific procedure codes signifying mental health/substance abuse service; excludes place of service = inpatient hospital|
|Percent with any inpatient mental health/substance abuse treatment||Inpatient||Number of children with mental health/substance abuse treatment in inpatient setting; includes stays with ICD-9-CM primary diagnoses = 290, 293-302, 306-316, 291-292, 303-305, 965.0, 965.8, 969 OR (primary diagnosis = 967 and secondary diagnosis = 291-292, 303, 305)|
|Average number of outpatient mental health/substance abuse visits per user||Other||Mean number of outpatient mental health/substance abuse visits; mean derived based on service users only|
|Average number of inpatient mental health/substance abuse days per user||Inpatient||Mean number of inpatient mental health/substance abuse days; mean derived based on service users only|
|a. To account for part-year eligibility, denominators for all utilization rates were measured in terms of number of full-year equivalents (calculated as the total number of eligible months divided by 12).|
1. This can include children receiving foster care assistance (both Title IV-E and non-Title IV-E), adoption subsidies (both Title IV-E and non-Title IV-E), and children in group homes or those who are otherwise wards of the state. The remaining seven states either do not identify foster care children or have problems with their eligibility data that make the states unsuitable for this study.
2. Data for Pennsylvania are from 1994. A SMRF file for 1995 is available, but it has significant data quality problems which prohibit it from being used for this study.
3. One of the limitations of the Georgia data was the omission of eligibility data for the first three months of 1994. This would censor the data to less than two full years of eligibility and claims history.
4. A health passport is a traveling medical record for children in foster care, which tracks their medical history and documents their health care utilization.
5. The SMRF file shows only one Medicaid eligibility category per month. Children were classified according to the eligibility category accounting for the majority of the eligibility period, with the exception of children in foster care who were classified in the foster care category if they were "even enrolled" in foster care during the year. Foster care children who received SSI benefits were counted in the foster care category only if the SMRF file identified one or more months of foster care eligibility. It is possible that some foster care children are counted in the SSI category if states code only their SSI eligibility on the SMRF file.
6. For this study, we excluded the pregnancy and newborn complications categories included in the CDPS. While these categories are relevant for purposes of risk adjustment (predicting higher costs in a subsequent year), they are not reflective of chronic illness or disability per se.
7. The diagnostic codes are: 650, 646.0-656.3 (fifth digit 1, 2), 656.5-676.9 (fifth digit 1, 2),V27.0, V27.2, V27.3, V27.5, V27.6, V27.9, V30-V39.21.
8. Two categories mental hospital for aged and skilled nursing facility/intermediate care facility (SNF/ICF) mental health services for aged were not applicable to this study. Another category ICF-all other was no longer in use. The premium payment category was not applicable since children enrolled in managed care were excluded from this study, and dental premiums in California were reported under the dental type of service.