Page 36 - Post-traumatic stress disorder in adults with mild intellectual disability: Screening, assessment, and brief intensive EMDR therapy

Chapter 2
al., 2023). As a result, PTSD symptoms may be wrongly attributed to these
disorders. The diagnosis of PTSD requires more than observing visible
behavior. A PTSD diagnosis requires knowledge of what traumatic events
a person may have experienced and could be linked to the emergence of
symptoms (American Psychiatric Association [APA], 2022). Undetected
and untreated PTSD in individuals in the general population has been
found to be associated with an elevated risk of other conditions, such as
substance abuse (Goldstein et al., 2016, revictimization (Graham-Kevan
et al., 2015), delinquency (Marsiglio et al., 2014), and decreased physical
health (Pietrzak et al., 2012). Therefore, a timely and adequate diagnosis of
PTSD is important in patients with MID-BIF (McNally et al., 2021).
A growing body of research has highlighted the need to assess individuals
with ID who have experienced psychological trauma. Although PTSD
symptoms manifest in people with MID-BIF in the same way as in
people without ID (Hoogstad et al., 2023; Mevissen et al., 2016, 2020), it
requires different diagnostic tools because questionnaires developed to
assess PTSD in people in the general population are often too difficult to
complete for people with MID-BIF due to the lack of simplified language
and supporting visualization (Kooijmans et al., 2022). A review by Daveney
et al. (2019) revealed that the adult version of the Diagnostic Interview
Trauma and Stressors – Intellectual Disability (DITS-ID-adults; Mevissen et
al., 2018) is the only instrument to establish a PTSD diagnosis in adults with
MID-BIF according to the DSM-5 criteria (American Psychiatric Association
[APA], 2013). The DITS-ID-adults is a clinical interview (taking approximately
45–60 minutes) and has been validated in a sample of 106 Dutch adults
with MID-BIF, living in supported housing or receiving ambulatory care
from an ID care service (Mevissen et al., 2020). The DITS-ID-adults proved
to be client-friendly, given that all participants in the study by Mevissen et
al. (2020) could complete the interview, and emotional dysregulation did
not occur. The interrater reliability of the DITS-ID-adults was good, and
its construct validity was supported by significant positive associations
between the scores on the Anxiety, Depression, and Mood Scale (ADESS)
and Impact of Event Scale – Intellectual Disabilities (IES-ID). However,
there are a few gaps in the study by Mevissen et al. (2020) that need to
be noted. First, anxiety and depression symptoms were measured using
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