Undiagnosed PTSD

Generally, in a clinical setting, doctors focus on a patient's chief complaint, and often do not inquire about trauma history, or PTSD-related symptoms. The authors of this study wanted to assess how doctors recognized and diagnosed (or failed to diagnose) PTSD.

1,000 patients were involved in the study, and split into two groups. The first group consisted of outpatient psychiatric subjects who were administered a broad questionnaire (Psychiatric Diagnostic Screening Questionnaire) that included a handful of PTSD questions. The second group was given a semi-structured diagnostic interview during their intake evaluation. The authors then compared the results of these tests to their own diagnosis of the patient. The design of the study allowed the authors to compare differences in evaluating patients by three different methods: at intake, with a semi-structured interview, or with a questionnaire.

The authors organized their data into three categories:

  • Patients diagnosed with PTSD.
  • Patients who screened positive, but were not diagnosed.
  • Patients who were neither diagnosed nor screened positive.

The following table summarizes the authors' findings:

In the Group Given the Screening Questionnaire (n=500)

Diagnosed by Clinician

36 (15 as principal diagnosis and 21 as an additional diagnosis)

Screened positive, but had no diagnosis


In the group given the intake interview, 72 patients were diagnosed immediately with PTSD. For 23 patients it was the principal diagnosis, and for 49 an additional diagnosis. The patients in both groups with PTSD tended to be younger, have more suicidal thoughts, were less likely to have a college degree, and had a higher number of symptoms.

The findings suggest PTSD is under-diagnosed in a clinical setting. The evidence that twice as many patients were diagnosed with the structured interview (conducted at intake), as opposed to the general questionnaire (conducted after clinical care), further supports their finding. The authors present a number of reasons to explain the discrepancy between screenings and doctor diagnoses. These include poor documentation or poor diagnostic skills: "...other reports have documented that clinicians underdetect trauma histories and PTSD diagnoses."

The authors discuss how this under-diagnosis can affect patients and their treatments. Failing to recognize PTSD may result in the patient not getting treatment that can help his or her condition. Correcting a problem is difficult if you aren't aware of the problem in the first place.

On the other hand, if both physician and patient recognize PTSD, proper and effective treatment could be presented and considered. The authors conclude:

"To date, there are no controlled trials comparing the efficacy of medications to cognitive behavioral therapy in the treatment of PTSD. If one form of treatment proves superior to the other, or if the combination of both treatments produces the greatest improvement, then improved clinical detection of PTSD should improve outcome by virtue of more appropriate treatment planning."

Zimmerman M, Mattia J. Is posttraumatic stress disorder underdiagnosed in routine clinical settings? The Journal of Nervous and Mental Disease 1999;187(7):420-427.