How do we know when posttraumatic stress disorder is getting better?

Posttraumatic stress disorder (PTSD) causes a great deal of mental and physical distress, and can significantly reduce a person’s quality of life. There are a number of effective treatments for PTSD that are available, but many people do not make meaningful improvements and are left with residual symptoms that cause persisting problems (Koek et al., 2016; Larsen, Fleming, & Resick, 2019).

Studies that report on the effectiveness of PTSD treatment are difficult to compare, because there are differences in terms of what is considered to be a response to treatment (i.e. someone getting better), and when someone is considered to have not responded (i.e. not gotten better) (Forbes et al., 2019; Sippel, Holtzheimer, Friedman, & Schnurr, 2018). This lack of a standard definition of what it means for a person to respond or not respond to PTSD treatment is in stark contrast to other areas of psychiatry that have well-developed definitions, such as depression or obsessive-compulsive disorder. More importantly, in the absence of a clear agreement on treatment response or non-response, it is difficult to effectively plan treatment and make timely clinical decisions such as when to cease, persist with or consider augmenting treatment.

In our study, we systematically reviewed definitions of response and non-response in all clinical trials testing PTSD treatments over the past few decades. Surprisingly, nearly a third of trials omitted a definition of response or non-response to treatment altogether. For trials that did supply a definition, they mostly used either a pre-determined percentage reduction in symptom severity scores across treatment (e.g., -15%) or a set reduction in scores on an assessment measure (e.g., – 15 points), or set a particular cut-off score on a clinician-rated assessment tool.  All of these approaches have their strengths and weaknesses.  Using the findings from the review, we have proposed a set of definitions we think represents a sound way forward and hope might be adopted in order to standardize what it means for someone to get better:

Construct Definition
Treatment response A reduction in an individual’s symptom between the start of treatment, to completion of treatment, by 30-50%. Ideally, treatment response definition should also take into account a range of functional and quality of life outcomes (e.g., functioning and coping skills) as well as other indicators of a “good end-state function” (e.g., depression and anxiety symptoms; Cuijpers, 2019; Yehuda & Hoge, 2016).


Having a score of less than or equal to 20-points on the Clinically Administered PTSD Scale (CAPS).


Maintaining a score of less than or equal to 20-points on the CAPS at a time point of at least 6-months after treatment completion.
Non-response The failure to meet the treatment response criteria
Worsening A persistent deterioration of symptoms
Treatment resistance A lack of clinically meaningful improvement despite receiving adequate treatment (Sippel et al., 2018)

By setting these definitions, we hope to improve clinical and research practice by increasing consistency. Defining these constructs will also help to facilitate the development of clinical algorithms to guide decision-making and treatment planning for those people with PTSD.

Discussion Questions

  1. How can researchers test the proposed definitions that we have presented here?
  2. Can we create an algorithm to guide decision-making and treatment planning for people who do not get better following PTSD treatment?
  3. Is it important to have function and quality of life included as essential outcomes of PTSD treatment?

Author Bios

Dr Tracey Varker is a Senior Research Fellow at Phoenix Australia and has over 15 years’ experience in posttraumatic mental health, working with emergency services and military personnel, traumatic injury patients, and survivors of natural disasters. Tracey is an expert in evidence synthesis, with a keen interest in synthesising and translating evidence to improve the lives of those affected by trauma.

Dr Dzenana Kartal is a Research Fellow at Phoenix Australia. She has experience working in public and university mental health research specialising in posttraumatic mental health problems among refugees and culturally and linguistically diverse communities. At Phoenix Australia, Dzenana specialises in mental health service delivery and research including implementation and evaluation of evidence-based treatments and knowledge translation.

Dr Mark Hinton is the Director of the Centenary of Anzac Centre’s Treatment Research Collaboration. A clinical psychologist by training, Mark has worked in a variety of mental health settings in clinical, management and academic roles over the course of a career spanning three decades. In line with the aims and objectives of the Centenary of Anzac Centre, Mark is committed to engaging services in relevant, high quality research designed to produce outcomes that will make a real difference to the mental health and wellbeing of veterans and their families.

Reference Article

Varker, T, Kartal, D, Watson, L, et al. Defining response and nonresponse to posttraumatic stress disorder treatments: A systematic review. Clin Psychol Sci Pract. 2020; 00:e12355.

References Cited

Cuijpers, P. (2019). Targets and outcomes of psychotherapies for mental disorders: An overview. World Psychiatry, 18(3), 276-285. doi:10.1002/wps.20661

Forbes, D., Pedlar, D., Adler, A. B., Bennett, C., Bryant, R., Busuttil, W., . . . Wessely, S. (2019). Treatment of military-related posttraumatic stress disorder: Challenges, innovations, and the way forward. International Review of Psychiatry. doi:10.1080/09540261.2019.1595545

Koek, R. J., Schwartz, H. N., Scully, S., Langevin, J.-P., Spangler, S., Korotinsky, A., . . . Leuchter, A. (2016). Treatment-refractory posttraumatic stress disorder (TRPTSD): A review and framework for the future. Progress in Neuro-Psychopharmacology & Biological Psychiatry, 70, 170-218. doi:10.1016/j.pnpbp.2016.01.015

Larsen, S. E., Fleming, C., & Resick, P. A. (2019). Residual symptoms following empirically supported treatment for PTSD. Psychological Trauma: Theory, Research, Practice, and Policy, 11(2), 207-215. doi:10.1037/tra0000384

Sippel, L. M., Holtzheimer, P. E., Friedman, M. J., & Schnurr, P. P. (2018). Defining treatment-resistant posttraumatic stress disorder: A framework for future research. Biological Psychiatry, 84(5), e37-e41. doi:10.1016/j.biopsych.2018.03.011

Yehuda, R., & Hoge, C. W. (2016). The meaning of evidence-based treatments for veterans with posttraumatic stress disorder. JAMA Psychiatry, 73(5), 433-434. doi:10.1001/jamapsychiatry.2015.2878

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