Alternative definitions of disability: changes in a dichotomous v continuous system

Alternative definitions of disability: changes in a dichotomous v continuous system

Abstract

d is a b il it y a n d r e h a b i l i t a t i o n , 1999 ; v o l . 21, n o . 8, 385± 387 Alternative de® nitions of disability: changes in a dichotomous v continuous system MAXWELL J. MEHLMAN and DUNCAN NEUHAUSER* Law-Medicine Centre and Department of Epidemiology and Biostatistics, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, Ohio 44106-4945 , USA Tepper et al. have done us a service by quantifying the consequences in terms of numbers of people and costs of care per person, for diŒ erent de® nitions of `disability’ . These authors rightfully make assumptions that underlie their work. Let us examine some of them. Why dichotomous variables ? Tepper et al." reinforce our view that disability is a continuous variable. Some people have more disability; some have less. A lot of information is lost by using just two categories. Alive or dead, male or female, cancer or non-cancerous, are useful dichotomies. Age, wealth, wisdom, beauty and pregnancy are not. Disability surely ® ts into the latter category, unless we wish to be more speci® c; `amputee’,