Of Pacemakers and Statistics: The Actuarial Method Extended

Pacemakers cease functioning because of either natural battery exhaustion (nbe) or component failure (cf). A study of four series of pacemakers shows that a simple extension of the actuarial method, so as to incorporate Normal statistics, makes possible a quantitative differentiation between the two modes of failure. This involves the separation of the overall failure probability density function PDF(t) into constituent parts pdf_nbe(t) and pdf_cf(t). The approach should allow a meaningful comparison of (he characteristics of different pacemaker types.