Table 2.

Independent Variables Used to Predict Transitions between Disability Benefit States, Death, and Annual Expenditures for Purposes of Estimating Cumulative Expenditures per Beneficiary under the DI, SSI, Medicare, and Medicaid Programs

Independent Variable	Predicted Variables
	Disability Benefit Status Transitions*	Death	DI Annual Expend.	SSI Annual Expend.	Medicare Parts A and B Annual Expend.	Medicare Part D Drug Annual Expend.	Medicaid Annual Expend.
Age	X	X			X	X	X
Sex	X	X			X	X	X
Primary diagnosis	X	X			X	X	X
History of end-stage renal disease		X			X	X	X
Current disability benefit status	X	X	X	X	X	X	X
History of DI	X				X	X
History of SSI	X					X	X
Level of monthly DI benefits (2000–2007)	X		X
Level of monthly SSI benefits (2000–2007)				X
Died					X	X	X

Note: Prediction equations are described in the Electronic Supplemental Material.

^*Transitions refer to year-to-year transitions between disability benefit states: DI ONLY; SSI ONLY; DI AND SSI; and NEITHER DI nor SSI.

DI, Social Security Disability Insurance; SSI, Supplemental Security Income, federal expenditures only.

Source. Social Security Administration and Centers for Medicare and Medicaid Services administrative records.