Who participates in PTSD treatment research? 

PTSD treatment studies may include people of all different backgrounds. Some studies look specifically at a certain type of people, such as a specific age group, gender identity, or racial or ethnic group. Other studies try to recruit participants of diverse backgrounds. We can learn different things from PTSD treatment studies that have a specific or broad sample (group of participants), so both types of studies are valuable. Learning who participates in research tells us how "generalizable" the results are. That is, we want to know whether the findings from given studies (or samples) apply to the rest of the population, or to ourselves if we are considering treatment.

How old are participants? 

The PTSD Repository includes clinical trials of adults, so in each study, participants were 18 years of age or older. Not all studies report participant age, 27 of the 496 studies did not.  The histogram below shows how the average (mean) age varies across studies that include information about participant age.

The most common average (mean) age of participant groups is 34-44--the "peak" age groups in the chart. Studies vary in terms of the age range of participants. Across all studies, the average age of the sample (which includes all participants) is 18 to 71. Some studies have a wide range of participant age, with standard deviations between 15-20 years, whereas other studies limit recruitment to a particular age group and narrower range. 
In the chart below, you can also use the filter to see how the average age of the sample varies by type of treatment being studied (by filtering "Study Class"). 

Are PTSD clinical trials gender diverse? 

Some of the earliest clinical trials of PTSD psychotherapies focused on women who experienced sexual assault. As trials turned to testing treatments among military Veterans with combat exposure, more men were included in research. Although women are slightly less likely to experience trauma in their lives, the prevalence of PTSD is slightly higher among women, and the types of traumatic events that are most likely to lead to PTSD (e.g., sexual assault, abuse during childhood) are more common among women.
We are also just beginning to learn more about the trauma and PTSD experiences of nonbinary and transgender people. As the field evolves, we will see RCTs specific to gender diverse and transgender people. Currently, none of the RCTs in the PTSD Repository are focused on these populations, although it is very likely that participants in studies included here include more diversity than reported. 
The chart shows the number of studies where samples are only women (the 100% bar) or all men (the 0% bar). The "Other" bar includes studies where the sample includes participants of any gender.

12% of trials are limited to men, and 14% of studies included exclusively women participants. The large majority (74%) of trials include both men and women.
In the PTSD Repository, only a small portion, 4% of studies, do not include gender information for participants. 

You can "drill down" in the chart by selecting a bar, which shows you the most common treatment types in the studies of men, women or mixed ("other") samples.

Are PTSD clinical trials racially and ethnically diverse? 

Although more work in this area is needed, research on how race and ethnicity relate to PTSD treatment helps us identify disparities and ensure that our treatments are effective for (and available to) everyone.
Only 6 out of every 10 studies (or 57%) included in the PTSD Repository report race information, and only 3 out of every 10 (or 31%) report the ethnic identity of participants. Just over half of studies that report about race also report ethnicity (54%); and, for only 3 studies, ethnicity is reported without race identity information.
You can click on a bar in the chart below to learn about race and ethnicity reporting by the type of treatment being studied (or "Study Class"). Studies with "No value" do not report race or ethnicity in the chart.

Learn more

Our story, Who has been studied in PTSD clinical trials?, includes more detail about participants in PTSD studies included in the PTSD Repository.