Predicting rehabilitation outcome for supplemental security income and social security disability income recipients: implications for consideration with the ticket to work program

Journal of Rehabilitation, July-Sept, 2005 by Jackie B. Rogers, Malachy Bishop, Ralph M. Crystal

Demographic Variables. In addition to the number and type of services received, we explored a number of demographic variables for their possible contribution to VR closure status prediction. These included gender, age, race, and education.

Gender. Gender was coded as a dichotomous variable. The final sample was 53.4% male, and 46.6% female.

Race. The predictor variable race was a polytomous variable with four levels, as defined by the RSA in the national database (White, Black, American Indian or Alaskan Native, and Asian or Pacific Islander). Race was operationalized as the race reported by clients on their application for VR services (RSA, 1995). This categorical variable was coded using the "simple" contrast method (Norusis, 1999) such that the group identified as Whites served as the reference category for this variable and was contrasted with each of the other three race groups. The sample was composed as follows: Whites comprised 74.1%, Blacks 23.1%, American Indians or Alaskan Natives 1%, and Asian or Pacific Islanders 1.7%. Note that the RSA reporting manual makes a distinction between race and Hispanic origin and does not identify a separate racial category for the Hispanic population. For the purpose of the analysis, therefore, the race variable only included the four categories identified above.

Education. The predictor variable education was a continuous variable. This variable was defined and coded as the highest grade completed at the time of application for VR services. The mean highest grade completed was 11.9 (SD = 2.37). The minimum was zero and the maximum was the 21st grade.

Age. Age at application was computed based on the date of birth and date of application. This was a continuous variable. The mean age of the sample was 40.9 years (SD = 13.13). The minimum age was 19 and the maximum was 95 years.

Severity of Disability. According to the RSA definition, a person has a severe disability if he or she has a mental or physical disability, or both, and this disability (a) severely limits the individual in functional capacities, (b) is expected to require multiple rehabilitation services, and (c) causes multiple substantial functional limitations. This variable is coded in the national database as a dichotomous, nominal variable, and was entered into the regression as such.

Results

Nine variables significantly contributed to the explanatory power of the model (2 (8, N=6264) = 24.391, p = .002). Together. these variables accounted for approximately 14% of the variance (Nagelkerke [R.sup.2] = .135). The results of the final stage of the analysis are summarized in Table 1. This model correctly predicted group membership 64.1% of the time. Specifically, the model accurately classified 58.8% of those who were closed "rehabilitated" (Status 26) and 70.1% of those who were closed "not rehabilitated" (Status 28).

Six VR services, including restoration, college or university training, on-the-job training, job placement, miscellaneous services, and other services were found to contribute to the explanatory value of the model. The percentages of consumers receiving each service are displayed in Table 3. The receipt of job placement services was found to be significantly related to closure status (Wald = 300.090, p = .000). The Exp (B) for job placement services (3.187) is interpreted as meaning that compared to people who did not receive job placement services, those who did were over three times more likely to be closed in status 26. People who received on-the-job training were over one and a half times more likely to be closed in Status 26 than those who did not (Wald 14.901, p = .000, Exp (B) = 1.628).