The descriptive analysis revealed a pattern of increasing multi-service utilization over the time period. The analysis by program type indicates that multi-service utilization is increasing for the special education and Medicaid service populations, but is the decreasing for the AABD service population. In order to further confirm the trends observed in the descriptive analysis, logistic regression was used to model the probability that a child would use multiple services during a fiscal year while controlling for demographic and disability characteristics.
Table 18 presents the odds ratios from each of the three models. Each program type was modeled separately because of the variation in the incidence of multi-service use. DMH multi-service utilization was not examined in the multivariate analysis because it was so rare. The odds ratios describe the effect on the probability of being a multi-service user during a fiscal year relative to a baseline group while holding all other factors constant For example in the model for AABD program participants, females are 20% less likely than males to be multi-service users during a fiscal year. Minority children in AABD were less likely to be multi-service users than were white children. The odds ratios of the age categories indicate that children between the ages of 8 and 13 are slightly more likely than children ages 6 to 7 to be multi-service users. It appears that the very young and teenage children were less likely to be using multiple services during a fiscal year. The direction of the indicators of fiscal year indicate a discontinuous upward trend in the likelihood that children in AABD used multiple services during the fiscal year. In FY 1991 and FY 1992, children were nearly two times more likely to be multi-service users than children in AABD in FY 1990. In FY 1993, however, children were slightly less likely to be multi-service users than children in FY 1990. This drop coincides with the dramatic increase in the AABD population after Zebley and the decreasing likelihood of new entrants to have had prior service experience in any of the other three disability programs. Although this decreasing likelihood of multi-service use persisted in the descriptive trend, after controlling for all other factors the direction of the FY 1994 indicator showed that children were more likely to have participated in multiple services than in FY 1990.
Model 2 presents the odds ratios for children participating in special education during each of the fiscal years. Unlike AABD, females in special education were slightly more likely than males to be multi-service users. Minority children were 2 to 3 times more likely to be multi-service users. With the exception of infants, the likelihood of being a multi-service users decreases with age. Children over the age of 7 are approximately 20% less likely to be multi-service users than children ages 6 and 7. The fiscal year indicators point to a slightly increasing likelihood of multi-service use among the special education population between FY 1992 and 1993. In FY 1994 however, children were 2.25 times more likely to be multi-service users than children participating in FY 1990 holding all other characteristics constant. In addition to the program and demographic characteristics already mentioned, the primary characteristic for each child per fiscal year was included in the model. The odds ratios show that mentally retarded children, physically disabled children and children with other disabilities were approximately 2 times more likely to be multi-service users than were severely emotionally disturbed children. Children with learning disabilities and speech or language disorders were nearly 70% less likely to be multi-service users during a fiscal year than were severely emotionally disturbed children.
In Model 3, the likelihood of being a multi-service user during a fiscal year is modeled for children participating in the Medicaid program. The effects of demographic and program indicators for the Medicaid program population tend to look similar to the effects in the Model 1. Females, for example, are 25% less likely than males to be multi-service users in a fiscal year. Hispanic and African-American children are slightly more likely than white children to be multi-service users during a fiscal year. In the Medicaid program population, children over the age of 7 are more likely to be multi-service users than are children ages 6 to 7. Like the special education population, children participating in the Medicaid program after FY 1990 are more likely to be multi-service users during the fiscal year than are children who participated in FY 1990. The description of the selection into the Medicaid program population was also included in the model in order to control for any effect of the type of disabling condition. Children selected due to mental diagnoses or a combination of mental and non-mental diagnoses were more likely to be multi-service users during a fiscal year than were children selected because of one or more non-mental diagnoses.