Just how frequently is PTSD diagnosed? The National Comorbidity Survey Replication (NCS-R), conducted between February 2001 and April 2003, comprised interviews of a nationally representative sample of 9,282 Americans aged 18 years and older. The NCS-R estimated the lifetime prevalence of PTSD among adult Americans to be 6.8%. The lifetime prevalence of PTSD among men was 3.6% and among women was 9.7%. Thus, the diagnosis is by no means uncommon.