<p>An equation to predict mortality in institutions has been devel­oped by Miller. Sabagh, and Dingman (1962). This equation was cross validated on a population of mentally ill in a state hospital in another state. The equation provided successful predictions of mor­tality (p &lt; .0001) even though the weights had been derived for a younger and more severely handicapped group. It was concluded that a better understanding and better predictions would follow if the analysis had been based on the mentally ill population.</p>