that, in general, questions of treatment efficacy are best addressed in high quality RCTs because the variability of treatments, outcome measures, course of the disorder, and patient and provider preferences make studies of other designs unreliable in making causal inferences. The committee further reasoned that the specific characteristics of PTSD (multiple symptom clusters, occurring in various combinations in patients), its measurement (multiple outcome measures, some with several scales), and its treatment (a wide range of pharmacotherapy and psychotherapy options) were of such heterogeneity and fragmentation that observational studies were unlikely to provide sufficiently valid and reproducible evidence to be considered in addition to the RCTs.

Data Abstraction

The committee developed an evidence table template and database for abstracting data from the included studies. Once the evidence table data were abstracted by staff, committee members worked in pairs to check the tables for completeness and to assess the quality of the study as well as its contribution to the evidence regarding efficacy of the treatment. The following information was extracted from all included studies if available: geographical location; setting; study design; interventions (including dose, duration, dose protocol, concurrent interventions, and clinician); population characteristics (including age, sex, race/ethnicity, education, trauma type and duration, concurrent medications, psychotherapies, and comorbidities); study inclusion and exclusion criteria; number screened, number enrolled, and completion rates; funding source; and results for PTSD outcomes as well as outcomes on depression, anxiety, and quality-of-life measures. Additionally, information was abstracted on whether or not adverse events were reported, if meeting diagnostic criteria after treatment was reported, and if the study included veterans.


The committee was charged with making conclusions about the strength of the available evidence for treatment modalities according to the following framework:

  1. Evidence is sufficient to conclude the efficacy of X in the treatment of PTSD.

  2. Evidence is suggestive but not sufficient to conclude the efficacy of X in the treatment of PTSD.

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