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PTSD in Children and Adolescents: Research Updates

Multicultural Conference (MCC)

Much has been discovered about posttraumatic stress disorder (PTSD) in the past forty years, but there exists some gaps in applying this knowledge to clinical practice. Misdiagnosis is a case in point. For example, in 2010 researchers published a study that examined the frequency with which PTSD was diagnosed in children and adolescents at two mental health programs in Pennsylvania (Miele & O’Brien, 2010). First, they reviewed the medical charts of the patients and found that the rates of diagnosis of PTSD were 2 percent at one site and 5 percent at the second site. This represented the recognition of PTSD when mental health clinicians used their routine practice. Next, the researchers conducted their own evaluations on all those patients with a standardized diagnostic interview for PTSD. With this more comprehensive and systematic tool, they found that the rates of diagnosis of PTSD were actually 48 percent at the first site and 45 percent at the second. In routine practice, mental health clinicians had been missing the diagnosis of PTSD around 90 percent of the time.
If this was a surprise to the researchers, it probably should not have been. While they were the first ones to demonstrate this problem in children and adolescents, they were not the first ones to demonstrate this problem. Two years earlier, a group of researchers from the University of Stellenbosch in South Africa published a very similar study. These researchers reviewed the medical charts of adults on an inpatient psychiatric unit and found that the rate of diagnosis of PTSD on the unit, as determined by routine practice, was 6 percent (van Zyl, Oosthuizen, & Seedat, 2008). Next the researchers selected forty patients at random from the inpatient population over a period of six months, conducted their own evaluations with a gold standard diagnostic interview, and found that the rate of diagnosis of PTSD was actually 40 percent. Again, in routine practice clinicians seemed to be missing the diagnosis of PTSD around 90 percent of the time.

There are many fascinating issues we need to understand better for the assessment and treatment of PTSD in youth, including developmental differences in symptom expression; what counts as traumatic events; the fickleness of memory; discrepancies between youth and caregiver reports; comorbidity; assessment of parenting; neurobiology; and optimal treatment strategies (Scheeringa, 2018). If I had to choose the three most important issues to highlight for clinical practice, I would select developmental differences, what counts as traumatic events, and optimal treatment strategies.

Developmental Differences: New Criteria for Very Young Children

When most people think of PTSD, they probably think of soldiers traumatized by horrific combat experiences. When PTSD was first recognized in the 1980s, the patients were mostly soldiers returning from combat (Kulka et al., 1990). Many professionals were understandably slow to accept the idea that children and adolescents could develop PTSD too—it was a common belief that children did not experience trauma often (Benedek, 1985). However, researchers have learned that two-thirds of youth have experienced at least one life-threatening traumatic event by age sixteen (Copeland, Keeler, Angold, & Costello, 2007). The four most common types of life-threatening events experienced were accidents, natural disasters, sexual abuse, and witnessing violence.

Researchers eventually showed that children and adolescents could develop PTSD just as easily as adults could (Breslau, Davis, Andreski, & Peterson, 1991), so the next logical question was whether very young children could develop PTSD. And if so, what was the youngest age possible to develop PTSD?

Detailed case studies exist of PTSD symptoms that developed in very young children between three and six years of age who experienced frightening medical procedures, physical abuse, attacks by dogs, kidnapping, sexual abuse, plane crashes, motor vehicle accidents, witnessed a father murder a mother, and others (Scheeringa, Zeanah, Drell, & Larrieu, 1995). The youngest cases of full PTSD are three years of age, although it may be possible to develop PTSD earlier in extraordinary situations. It makes sense that three years of age is the lower age limit because this is the time when capacities for language and autobiographical narratives emerge (Scheeringa & Gaensbauer, 2000).

Through a series of group studies from multiple sites on a wide range of types of trauma, guidelines were established for how to diagnose posttraumatic problems in very young children with developmentally sensitive methods. The diagnostic criteria for PTSD in very young children have now been scientifically validated in nearly a dozen studies (Scheeringa, Zeanah, & Cohen, 2011). In 2013, the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) created a new category called “PTSD in Children Six Years and Younger” (APA, 2013). This was the first ever (and thus far the only) developmental subtype of a major psychiatric disorder to appear in the DSM classification system. That is not to say that the assessment of young children is not without challenges. The difficulties of assessing young children are described in detail in Scheeringa, 2018 (p. 57–82).

Furthermore, studies are suggesting that seven- to twelve-year-old children probably need modified diagnostic criteria too. Using similar developmental modifications to the diagnostic criteria used in the “PTSD for Children Six Years and Younger” criteria, Meiser-Stedman and colleagues (2008) showed that the modified criteria resulted in twice as many seven- to ten-year-old children being diagnosed with PTSD compared to the DSM-IV criteria (Meiser-Stedman, Smith, Glucksman, Yule, & Dalgleish, 2008). In addition, Iselin and colleagues (2010) showed that the modified criteria resulted in three times as many six- to fifteen-year-old children being diagnosed compared to the DSM-IV criteria (Iselin, LeBrocque, Kenardy, Anderson, & McKinlay, 2010). There will not be an opportunity to formalize a developmentally-appropriate set of diagnostic criteria until the DSM-6 process begins several years from now, but clinicians ought to note this when assessing seven- to twelve-year-old victims of trauma.

Qualifying Traumatic Events: Not All Stressful Events Are Traumatic Events

Consistent with the trend for greater recognition of PTSD in youth, there is another trend that seems less constructive and more troubling. With the increasing popularity of PTSD, more and more different types of events are being claimed to be “traumatic.” What we might call “bracket creep”—that is, events that most individuals would consider just stressful—has been elevated to the category of traumatic, creating an ever-widening list of life experiences that might cause PTSD.

One example of this bracket creep is a study about divorce. A British psychologist conducted surveys of 427 eleven- to sixteen-year-old youths recruited from six schools in England. Researchers asked if PTSD symptoms were related to, among other events, divorce of their parents. Of those who reported that their parents had separated or divorced, an amazingly high percentage of youths reported a high enough severity of PTSD from that specific event to have probable PTSD diagnoses (Joseph, Mynard, & Mayall, 2000). A whopping 29 percent of males and 39 percent of females appeared to have PTSD because they suffered through the divorces of their parents. Even more astounding was that these rates of probable PTSD were higher than the rates of PTSD for individuals who experienced a direct life threat to themselves, witnessed an attack on someone else, or lived through disasters.

In other examples, PTSD symptoms have been reported in adults experiencing financial problems (Scott & Stradling, 1994); Dutch farmers who had to put down their cattle due to foot and mouth disease, about half of which reported severe PTSD symptoms (Olff, Koeter, Van Haaften, Kersten, & Gersons, 2005); and inhabitants along the Gulf Coast who lived more than forty miles away from the Deepwater Horizon oil spill of 2010, approximately 28 percent of which scored above a cutoff for PTSD (Mong, Noguchi, & Ladner, 2012). Most recently, a study estimated that 25 percent of college students have clinically significant severity of PTSD symptoms due to the stress of the 2016 US presidential election (Hagan, Sladek, Luecken, & Doane, 2018). It is unlikely that the participants in those studies truly have PTSD symptoms. The reason that they can appear to have PTSD symptoms when they do not is because respondents can loosely interpret what counts as traumatic events, or the instructions on questionnaires often are not clear enough.

My research team once evaluated a sixteen-year-old female for possible participation in one of my treatment studies of youth with PTSD. Prior to the assessment, her mother told us over the phone that her traumatic events were the accidental death of her brother and the recent suicide attempt of her sister, who cut her wrists rather deeply. We were utterly surprised when, during the assessment, she considered that her own recent breakup with her boyfriend to be the most traumatic event in her life, and furthermore, the only traumatic event in her life.

This teenager did not consider her brother’s death or her sister’s suicide attempt to be traumatic events. She endorsed six symptoms of PTSD related to the breakup and was clearly enormously distressed by these symptoms. She met enough criteria for the diagnosis of PTSD, but because the breakup event did not meet the definition of a life-threatening traumatic event, I would not enroll her in our study and I do not believe she ever had PTSD.

So why is bracket creep a problem? The main reason is that confusing stress with trauma and PTSD could mean that patients receive the wrong treatment. A trainee met with me once to discuss if I would supervise her on treating a six-year old boy with cognitive behavioral therapy (CBT) for PTSD. The boy was in foster care because his mother was in jail on drug charges. When police entered the home, they also decided to charge the mother with neglect because this boy and his siblings were in the home unsupervised and without food. The trainee had assumed incorrectly that the experiences of neglect and being separated from his mother were traumatic stressors because she had been taught, through a variety of lectures and readings, that neglect and separation counted as trauma. She interpreted his symptoms of stashing food, aggression, sleep difficulty, and lack of concentration as a diagnosis of PTSD. The trainee had already conducted the first three psychotherapy sessions of the CBT protocol and hoped that I would help her on the remaining sessions. Instead, we backed up and reviewed the case. Based on all the available information, the child had actually never experienced a traumatic event. Furthermore, the child did not exhibit distress or avoidance of reminders of possible abuse or violence that might be clues for traumatic events we did not know about. If the trainee had continued with CBT, the therapy would have hit a dead end and valuable time would have been wasted on the wrong treatment.

Bracket creep also causes a problem for research. Against this backdrop of bracket creep, some researchers have argued that repeated, chronic, and interpersonal stress can cause a different type of syndrome that is more severe and complicated than PTSD. These types of stressors can include DSM-qualified life-threatening traumas, but can also include many types of events that are not life-threatening such as neglect, lack of parental supervision, emotional abuse, poverty, maternal depression, parental substance abuse, and living in violent neighborhoods. The experience of these multiple types of events has been called “complex trauma.” The alleged syndrome that follows from complex trauma has been given various names, but lately seems to be referred to most often as “complex PTSD.”

Studies, however, do not support the notion of complex trauma causing a distinct syndrome of complex PTSD. Advocates of this notion have claimed to find empirical support from preliminary cross-sectional studies (Cloitre et al., 2009; Finkelhor, Ormrod, & Turner, 2007; Ford, Connor, & Hawke, 2009), but they have failed to produce diagnostic validation studies with the most basic types of data needed to support a new syndrome. It is important for clinicians to keep in mind that studies about so-called complex trauma are studying something quite different from PTSD because the subjects in those studies may not have ever experienced true life-threatening traumas, and those studies cannot provide any new knowledge about PTSD.

The definition of what counts as potentially traumatic events should not be confusing. The definition of traumatic events in the DSM is clear. Since 1980, when the third edition of the DSM first formalized PTSD, the definition of traumatic events was “ . . . an event that is ‘generally outside the range of human experience’ and would ‘evoke significant symptoms of distress in most everyone’” (Cahill & Pontoski, 2005). This definition of trauma as life-threatening has been consistently carried through in both the DSM-IV (APA, 1994) and the DSM-5 (APA, 2013).

Stress is not the same as trauma. Everyone feels stress nearly every day. Trauma is different from stress primarily on the basis that trauma is life-threatening. By the nature of life-threatening events, traumatic events are also often sudden and unexpected. This combination of life-threatening, sudden, and unexpected is what creates moments of intense panic in which people fear for their lives. Stress, on the other hand, is not life-threatening and is usually very predictable.

Treatment: CBT for PTSD Improves Comorbid Disorders Too

CBT is by far the most well-studied treatment for PTSD. The best-known version of CBT for youths, called “trauma-focused cognitive behavioral therapy” (Cohen, Mannarino, & Deblinger, 2006), has been highly effective in multiple randomized clinical trials. There are other versions of CBT focused on trauma that appear effective too (Carrion, Kletter, Weems, Berry, & Rettger, 2013; Scheeringa & Weems, 2014).

Evidence-based treatments (EBT) for PTSD, namely CBT, appear to be heavily underutilized. Despite the enormous expenditure to disseminate EBTs in the last three decades, few clients in community clinics actually receive EBTs. In a 2009 review of the literature, we found that less than half of patients with a variety of disorders received EBTs, and even when an EBT was delivered, it was delivered suboptimally (Shafran et al., 2009). In one clinic, which was actually devoted to providing CBT, of 150 adult patients with PTSD only 28 percent completed a course of CBT (Zayfert et al., 2005). There are multiple reasons why CBT is underutilized, and one of them seems to be the diagnostic confusion presented by comorbidity.

One of the most consistent findings in all psychiatric research is that PTSD is comorbid with at least one other disorder 80 to 90 percent of the time. The high rate of co-occurring disorders with PTSD has been found across all age groups, races, and types of trauma. In adults, the co-occurring disorders are usually major depressive disorder, generalized anxiety disorder, and alcohol or drug abuse. In one of the larger adult studies, researchers found that patients who were currently diagnosed with PTSD also currently had major depression 69 percent of the time, generalized anxiety disorder 38 percent of the time, and panic disorder 23 percent of the time (Brown, Campbell, Lehman, Grisham, & Mancill, 2001).

In very young children, co-occurring disorders are different because of their different developmental level. In a study of three- to six-year-old trauma victims, we found that the young children diagnosed with PTSD were also diagnosed with oppositional defiant disorder 75 percent of the time, separation anxiety disorder 63 percent of the time, and attention-deficit/hyperactivity disorder 38 percent of the time (Scheeringa, Zeanah, Myers, & Putnam, 2003).

These comorbid disorders potentially cause problems because they are typically externalizing types of problems that are more easily recognized by parents and clinicians. Remembering also that the diagnosis of PTSD is missed most of the time (Miele & O’Brien, 2010; van Zyl et al., 2008), it has been known to happen where patients have been treated for a comorbid disorder while the PTSD was never recognized and treated. After much wasted time, money, and distress, once the PTSD was recognized and properly treated, the comorbid problems also improved.

We recently completed a CBT trial treating PTSD in children and adolescents (Scheeringa & Weems, 2014). Participants who received CBT saw significantly improved PTSD symptoms, but they also had improved depression, anxiety, oppositional defiant disorder, and the inattention and hyperactivity problems seen in attention-deficit/hyperactivity disorder. These results are consistent with other trials of CBT for PTSD in youth, showing that depression and anxiety improve concurrently with improvements in PTSD (Cohen, Deblinger, Mannarino, & Steer, 2004).

We have also seen similar results with very young children, especially as we completed the only randomized trial to treat PTSD symptoms in young children who had experienced any type of trauma (Scheeringa, Weems, Cohen, Amaya-Jackson, & Guthrie, 2011). Twenty-five three- to six-year-old children completed my twelve-session, manualized protocol of CBT called “Preschool PTSD Treatment.” The children in this case not only showed improvement on PTSD symptoms, but also on depression, separation anxiety, and oppositional defiance.

New Directions in Treatment

While current treatments help most patients with PTSD improve, newer treatments are being tested for those who are minimal responders or nonresponders to traditional techniques. One of these treatment strategies is to augment CBT with an additional intervention that is thought to enhance certain aspects of cognitive processing. D-cycloserine (DCS) is an antibiotic that has been used for tuberculosis for over fifty years, was found to have antianxiety properties, and is thought to enhance learning and facilitate extinction of fear responses. Studies in patients with phobias and OCD have shown that when DCS is administered one hour prior to CBT sessions, patients improve more and sometimes more rapidly compared to CBT alone (Matais-Cols et al., 2017). We conducted the only test so far in youth with PTSD (Scheeringa & Weems, 2014).

There was a trend toward DCS speeding PTSD symptom recovery during the exposure-based sessions, but overall (unfortunately), the addition of DCS to CBT did not improve outcomes, which was consistent with the only similar study in adults with PTSD (de Kleine, Hendriks, Kusters, Broekman, & van Minnen, 2012). Because PTSD involves complex, life-threatening trauma memories as opposed to imagined dreadful outcomes in other anxiety disorders, the use of DCS with PTSD may require greater attention to how its use is coupled with exposure-based techniques. DCS may have inadvertently enhanced reconsolidation of trauma memories, rather than more positive and adaptive memories. Secondary analyses suggested that the CBT+DCS group better maintained stability of gains on inattention ratings from posttreatment to the three-month follow up. Future research could focus on the longer-term benefits of DCS on attention and ways to capitalize on attention-enhancing therapies.

A second type of new treatment which appears more promising is computer-based bias modification. Bias modification is based on the principle that individuals with PTSD have underlying biases that are outside their conscious awareness. Biases can exist at the attention level and/or at the interpretation level. Individuals with attention bias attend preferentially to threatening stimuli, so computer-based attention modification tasks train them to shift their attention to more positive stimuli. Individuals with interpretation bias can interpret situations in life as more threatening, so computer-based cognitive bias modification tasks train them to interpret situations as more positive. Whereas CBT is presumed to work from a top-down approach by working with conscious thoughts and feelings, bias modification techniques work from a bottom-up approach by targeting unconscious activities with no explicit discussions, telling patients what or how to change.

There is a growing body of research using a variety of different tasks, and a review of these studies showed promising results for altering attention bias in nonclinical populations, but clinical implications were less clear. In contrast, interpretation bias modification has shown more consistent clinical effects (Woud, Verwoerd, & Krans, 2017). These appear to be promising, nonmedication, low-cost techniques that may either stand alone or be used as adjuncts to psychotherapy, although no known studies on youth have been conducted yet.

Summary and Conclusion

Missed diagnoses pose a major impediment to timely treatment and indicate an area where parents need to be involved (Scheeringa, 2018). Parents may have to be strong advocates to get doctors to recognize PTSD, and clinicians ought to encourage parents to do self-administered assessments of their children independently and at home, if need be. PTSD questionnaires are available for free online. ‘A mother of a boy we treated once told the therapist that recognition of the boy’s trauma, after years of being misdiagnosed, had been the turning point for finally getting the help that he needed (Scheeringa, 2018). It is important to remember these three things:

  1. When seeing young children, do not forget that they can develop PTSD too.
  2. When assessing new clients, do not forget that life-threatening events, not everyday stressors, are the events that typically cause PTSD.
  3. When treating patients, remember that an evidence-based treatment for PTSD often improves the comorbid disorders at the same time and is usually the most efficient treatment.

Following these principles can lead to positive changes in the lives of youth struggling with PTSD.


American Psychiatric Association (APA). (1994). Diagnostic and statistical manual of mental disorders (4th ed.). Washington, DC: Author.

American Psychiatric Association (APA). (2013). Diagnostic and statistical manual of mental disorders (5th ed.). Washington, DC: Author.

Benedek, E. P. (1985). Children and psychic trauma: A brief review of contemporary thinking. In S. Eth & R. S. Pynoos (Eds.), Posttraumatic stress disorder in children (pp. 1–16). Washington, DC: American Psychiatric Publishing.

Breslau, N., Davis, G. C., Andreski, P., & Peterson, E. (1991). Traumatic events and posttraumatic stress disorder in an urban population of young adults. Archives of General Psychiatry, 48(3), 216–22.

Brown, T. A., Campbell, L. A., Lehman, C. L., Grisham, J. R., & Mancill, R. B. (2001). Current and lifetime comorbidity of the DSM-IV anxiety and mood disorders in a large clinical sample. Journal of Abnormal Psychology, 110(4), 585–99.

Cahill, S. P., & Pontoski, K. (2005). Posttraumatic stress disorder and acute stress disorder I: Their nature and assessment considerations. Psychiatry, 2(4), 14–25.

Carrion, V. G., Kletter, H., Weems, C. F., Berry, R. R., & Rettger, J. P. (2013). Cue-centered treatment for youth exposed to interpersonal violence: A randomized controlled trial. Journal of Traumatic Stress, 26(6), 654–62.

Cloitre, M., Stolbach, B. C., Herman, J. L., van der Kolk, B. A., Pynoos, R. S., Wang, J., & Petkova, E. (2009). A developmental approach to complext PTSD: Childhood and adult cumulative trauma as predictors of symptom complexity. Journal of Traumatic Stress, 22(5), 399–408.

Cohen, J. A., Deblinger, E., Mannarino, A. P., & Steer, R. A. (2004). A multisite, randomized controlled trial for children with abuse-related PTSD symptoms. Journal of the American Academy of Child Psychology, 43(4), 393–402.

Cohen, J. A., Mannarino, A. P., & Deblinger, E. (2006). Treating trauma and traumatic grief in children and adolescents. New York, NY: The Guilford Press.

Copeland, W. E., Keeler, G., Angold, A., & Costello, E. J. (2007). Traumatic events and posttraumatic stress in childhood. Archives of General Psychiatry, 64(5), 577–84.

de Kleine, R. A., Hendriks, G. J., Kusters, W. J., Broekman, T. G., & van Minnen, A. (2012). A randomized placebo-controlled trial of D-cycloserine to enhance exposure therapy for posttraumatic stress disorder. Biological Psychiatry, 71(11), 962–8.

Finkelhor, D., Ormrod, R. K., & Turner, H. A. (2007). Polyvictimization and trauma in a national longitudinal cohort. Development and Psychopathology, 19(1), 149–66.

Ford, J. D., Connor, D. F., & Hawke, J. (2009). Complex trauma among psychiatrically impaired children: A cross-sectional, chart-review study. The Journal of Clinical Psychiatry, 70(8), 1155–63.

Hagan, M. J., Sladek, M. R., Luecken, L. J., & Doane, L. D. (2018). Event-related clinical distress in college students: Responses to the 2016 US presidential election. Journal of American College Health, October, 1–5.

Iselin, G., Le Brocque, R., Kenardy, J., Anderson, V., & McKinlay, L. (2010). Which method of posttraumatic stress disorder classification best predicts psychosocial function in children with traumatic brain injury? Journal of Anxiety Disorders, 24(7), 774–9.

Joseph, S., Mynard, H., & Mayall, M. (2000). Life events and posttraumatic stress in a sample of English adolescents. Journal of Community & Applied Social Psychology, 10(6), 475–82.

Kulka, R. A., Schlenger, W. E., Fairbank, J. A., Hough, R. L., Jordan, B. K., Marmar, C. R., & Weiss, D. S. (1990). Trauma and the Vietnam war generation: Report of findings from the National Vietnam Veterans Readjustment Study. Philadelphia, PA: Brunner/Mazel.

Matais-Cols, D., Fernández de la Cruz, L., Monzani, B., Rosenfield, D., Andersson, E., Pérez-Vigil, A., . . . Thuras, P. (2017). D-cycloserine augmentation of exposure-based cognitive behavior therapy for anxiety, obsessive-compulsive, and posttraumatic stress disorders: A systematic review and meta-analysis of individual participant data. JAMA Psychiatry, 74(5), 501–10.

Meiser-Stedman, R., Smith, P., Glucksman, E., Yule, W., & Dalgleish, T. (2008). The posttraumatic stress disorder diagnosis in preschool- and elementary school-age children exposed to motor vehicle accidents. American Journal of Psychiatry, 165(10), 1326–37.

Miele, D., & O’Brien, E. J. (2010). Underdiagnosis of posttraumatic stress disorder in at-risk youth. Journal of Traumatic Stress, 23(5), 591–8.

Mong, M. D., Noguchi, K., & Ladner, B. (2012). Immediate psychological impact of the Deepwater Horizon oil spill: Symptoms of PTSD and coping skills. Journal of Aggression, Maltreatment & Trauma, 21(6), 691–704.

Olff, M., Koeter, M. W., Van Haaften, E. H., Kersten, P. H., & Gersons, B. P. (2005). Impact of a foot and mouth disease crisis on posttraumatic stress symptoms in farmers. The British Journal of Psychiatry, 186(2), 165–6.

Scheeringa, M. S. (2018). They’ll never be the same: A parent’s guide to PTSD in youth. Las Vegas, NV: Central Recovery Press.

Scheeringa, M. S., & Gaensbauer, T. J. (2000). Posttraumatic stress disorder. In C. H. Zeanah, Jr. (Ed.), Handbook of infant mental health (2nd ed.) (pp. 369–81). New York, NY: The Guilford Press.

Scheeringa, M. S., & Weems, C. F. (2014). Randomized placebo-controlled D-cycloserine with cognitive behavior therapy for pediatric posttraumatic stress. Journal of Child and Adolescent Psychopharmacology, 24(2), 69–77.

Scheeringa, M. S., Weems, C. F., Cohen, J. A., Amaya-Jackson, L., & Guthrie, D. (2011). Trauma-focused cognitive-behavioral therapy for posttraumatic stress disorder in three- through six-year-old children: A randomized clinical trial. Journal of Child Psychology and Psychiatry, 52(8), 853–60.

Scheeringa, M. S., Zeanah, C. H., & Cohen, J. A. (2011). PTSD in children and adolescents: Toward an empirically based algorithm. Depression and Anxiety, 28(9), 770–82.

Scheeringa, M. S., Zeanah, C. H., Drell, M. J., & Larrieu, J. A. (1995). Two approaches to the diagnosis of posttraumatic stress disorder in infancy and early childhood. Journal of the American Academy of Child and Adolescent Psychiatry, 34(2), 191–200.

Scheeringa, M. S., Zeanah, C. H., Myers, L., & Putnam, F. W. (2003). New findings on alternative criteria for PTSD in preschool children. Journal of the American Academy of Child and Adolescent Psychiatry, 42(5), 561–70.

Scott, M. J., & Stradling, S. G. (1994). Posttraumatic stress disorder without the trauma. British Journal of Clinical Psychology, 33(1), 71–4.

Shafran, R., Clark, D. M., Fairburn, C. G., Arntz, A., Barlow, D. H., Ehlers, A., . . . Wilson, G. T. (2009). Mind the gap: Improving the dissemination of CBT. Behaviour Research and Therapy, 47(11), 902–9.

van Zyl, M., Oosthuizen, P. P., & Seedat, S. (2008). Posttraumatic stress disorder: Undiagnosed cases in a tertiary inpatient setting. African Journal of Psychiatry, 11(2), 119–22.

Woud, M. L., Verwoerd, J., & Krans, J. (2017). Modification of cognitive biases related to posttraumatic stress: A systematic review and research agenda. Clinical Psychology Review, 54, 81–95.

Zayfert, C., Deviva, J. C., Becker, C. B., Pike, J. L., Gillock, K. L., & Hayes, S. A. (2005). Exposure utilization and completion of cognitive behavioral therapy for PTSD in a “real world” clinical practice. Journal of Traumatic Stress, 18(6), 637–45.

Michael Scheeringa, MD, MPH, is professor in the Department of Psychiatry at Tulane University School of Medicine, and holder of the endowed Venancio Antonio Wander Garcia IV, MD, Chair of Psychiatry. His studies on diagnostic validation, neurobiology, and evidence-based treatments have pioneered many firsts in the field of pediatric PTSD. Dr. Scheeringa is the author of two books on PTSD in youth