Definition of Psychological Trauma and Threshold for Functional Impairment in PTSD
To the Editor: Diagnostic criteria for posttraumatic stress disorder (PTSD) are often debated.1 With the forthcoming publication of DSM-5 and recent changes in US Department of Veterans Affairs (VA) PTSD disability policies, such discussions are especially relevant regarding the definition of psychological trauma (Criterion A) and threshold for functional impairment. Some have proposed dropping one or both components of PTSD Criterion A,2 while others have suggested that Criterion A1 (the objective traumatic event) and A2 (a subjective response of "fear, helplessness, or horror" to the event) be retained or reworded.3 Moreover, the VA has recently enacted policy changes that loosen disability criteria for establishing evidence of traumatic event exposure, while proponents of the "bracket creep hypothesis"4 express concern that the definition of trauma is too broad and further expansion will result in increased PTSD prevalence.5 Some propose A2 should be eliminated because it lacks predictive power beyond Criterion A1.6
Method. We examined rates of probable PTSD diagnoses as they relate to Criterion A and functional impairment in a cross-sectional sample of ethnically diverse college students from Hawaii (N = 614).7 Participants were asked about lifetime history of potentially traumatic experiences and whether or not their response during these events involved intense fear, hopelessness, or horror. Probable PTSD diagnoses were assessed using the 10-item Trauma Screening Questionnaire (TSQ), a screening instrument with (yes/no) responses based on DSM-IV diagnostic criteria-defined PTSD symptoms experienced at least twice in the past week.8 Participants were also asked to indicate how much symptoms interfered with or caused difficulties in their life during the past week (functional impairment), rated on a 0 to 4 (not at all to extremely) scale. We examined how rates of probable PTSD changed based on different use of Criteria A1 and A2 and functional impairment.
Results. Rate of probable PTSD diagnoses disregarding A1 and A2 criteria was 18.6%. Restricting probable PTSD diagnosis to those meeting criterion A1 reduced probable PTSD rate to 16.4%, while restricting to those meeting A1 and A2 reduced probable PTSD rate to 12.6%. A total of 64.7% who endorsed Criterion A1 also endorsed A2. With regard to functional impairment, 7.8% of the sample met a probable PTSD diagnosis (including A1 and A2) and also indicated that their symptoms interfered in their life "a moderate amount" or more (functional impairment score > 2) compared with 2.5% of participants with functional impairment scores greater than 3 ("quite a bit" or more).
Our findings are consistent with prior research9 and indicate that most participants who endorsed criterion A1 and met a probable PTSD diagnosis also endorsed criterion A2, though a small number did not. Since adding criterion A2 had minimal impact on the rate of probable PTSD, our findings may support dropping criterion A2 from PTSD diagnostic criteria. On the other hand, altering the threshold for functional impairment (Criterion F) had a pronounced effect on rate, which points to its significance as one of the important diagnostic criteria. PTSD rates are likely to rise or fall significantly depending on how rigorously functional impairment is conceptualized and measured.
References
1. Elhai JD, Grubaugh AL, Kashdan TB, et al. Empirical examination of a proposed refinement to DSM-IV posttraumatic stress disorder symptom criteria using the National Comorbidity Survey Replication data. J Clin Psychiatry. 2008;69(4):597-602. PubMed doi:10.4088/JCP.v69n0411
2. Brewin CR, Lanius RA, Novac A, et al. Reformulating PTSD for DSM-V: life after criterion A. J Trauma Stress. 2009;22(5):366-373. PubMed doi:10.1002/jts.20443
3. North CS, Suris AM, Davis M, et al. Toward validation of the diagnosis of posttraumatic stress disorder. Am J Psychiatry. 2009;166(1):34-41. PubMed doi:10.1176/appi.ajp.2008.08050644
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7. Archambeau OG, Frueh BC, Deliramich AN, et al. Interpersonal violence and mental health outcomes among Asian American and Native Hawaiian/Other Pacific Islander college students. Psychol Trauma. 2010;2:273-283.
8. Brewin CR, Rose S, Andrews B, et al. Brief screening instrument for posttraumatic stress disorder. Br J Psychiatry. 2002;181:158-162. PubMed
9. Long ME, Elhai JD, Schweinle A, et al. Differences in posttraumatic stress disorder diagnostic rates and symptom severity between Criterion A1 and non-Criterion A1 stressors. J Anxiety Disord. 2008;22(7):1255-1263. PubMed doi:10.1016/j.janxdis.2008.01.006
Author affiliations: Department of Psychology, University of Hawaii, Hilo (Ms Archambeau); Department of Psychology, University of Toledo, Toledo, Ohio (Dr Elhai); and The Menninger Clinic, Houston, Texas (Dr Frueh). Potential conflicts of interest: None reported. Funding/support: This work was partially supported by grant MH074468 from the National Institute of Mental Health (NIMH) and by the McNair Foundation (Dr Frueh).
doi:10.4088/JCP.10l06592
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