Author and journalist 
Mind Matters, the "blog seminar" I edit at sciam.com, this week hosts a debate (which readers can join) about a) how best to estimate the prevalence of post-traumatic stress syndrome (PTSD) in Vietnam veterans and b) ultimately, how to calculate the cost-benefit ratio of war. Three researchers (Harvard psychologist Richard J. McNally, UC San Francisoc psychiatrist Charles Marmar, and psychologist William Schlenger, of Abt Associates) with a long history of work in PTSD among Vietnam vets grapple with the implications of a recent study that seemed to revise sharply downward long-standing estimates of how many Vietnam veterans suffered PTSD. As you'll see, it's a difficult issue and a lively debate. As I note in the intro to the researchers' comments, our mixed feelings about Vietnam haunt this entire discussion:
What proportion of U.S. veterans of the Vietnam War developed post-traumatic stress syndrome, or PTSD, in reaction to their service there? That answering this question proves difficult shouldn't surprise, for the definition of PTSD has a history almost as controversial as that of the Vietnam War. ...
This is partly because the stakes are high: We can't properly treat PTSD in veterans, whether of past, present, or future wars, if we don't know its prevalence. In addition, assessing our troops' trauma inevitably feeds the ongoing debate over war's cost-benefit ratio. This debate is difficult at any time -- and torturous indeed when a war's benefits prove elusive. This happened in Vietnam and appears to be happening now in Iraq. Small wonder that this simple question -- How much trauma have we inflicted on our veterans? -- can prove excruciatingly painful to answer.
Check it out at Mind Matters. And feel free to chime in with comments or questions via the usual link at the bottom of the column there.
