"Coverage" means that if a method has a stated coverage of 50 percent, then approximately 50 percent of the individuals in a particular pubic symphyseal stage should have ages that are between the stated age limits; and that approximately 25 percent should be below the bottom age limit and 25 percent above the top age limit. The pubic symphysis has a lengthy history in estimating ages and in providing evidence for estimating age-at-death. Still, the reliability of this method is unclear, primarily because ad hoc statistical methods have been applied in previous studies. The current study made extensive use of "transition analysis" (Boldsen et al.). This is a parametric method for modeling the passage of individuals from a given development stage to the next higher stage in an ordered sequence. In the current example, there are six ordered phases within the Suchey/Brooks pubic symphyseal system, so five transition distributions must be modeled: one between phase I and II, one between II and III, one between III and IV, one between IV and V, and one between V and VI. This procedure is described in detail. In a number of applications the study showed that if an appropriate prior age-at-death distribution is used, then transition analysis will provide accurate "coverages;" whereas, percentile methods, range methods, and mean (plus or minus standard deviations) will not. 4 tables, 20 figures, and 56 references