37,650 ways to have “persistent complex bereavement disorder” yet only 48 ways to have “prolonged grief disorder”

Persistent complex bereavement disorder (PCBD) is a condition for further study in the Diagnostic and Statistical Manual of Mental Disorders-5. Prolonged grief disorder (PGD) will likely be included in the International Classification of Diseases'−11. While it has been argued that PCBD and PGD cover the same diagnostic entity, their symptom count differs. A higher symptom count may increase the complexity of diagnostic algorithm and thereby the symptom profile heterogeneity of a disorder. Using binomial equations, a nearly thousand-fold difference in possible symptom profiles to meet PGD versus PCBD criteria was demonstrated, showing both disorders may differ more than just semantically.