EMDR treatment

The intervention consists of 10 weekly EMDR sessions of 60 minutes and targets stressful daily life (i.e. a situation that caused anger, fear or confusion) events rather than traumatic images from the past. For each session, a standardised EMDR protocol is used that consists of the following consecutive steps: 1) determining and visualising a confusing and/or stressful daily life event that occurred during the past week; 2) formulating a negative and a positive thought based on the chosen event; 3) determining the amount of stress that is evoked by the chosen event; 4) patient focuses on the chosen event while being presented with a distracting stimulus; 5) evaluating the amount of stress that is caused by the chosen event; 6) linking positive thoughts to the negative one when the stress caused by the chosen event does no longer exist; 7) evaluation and closure of session.

Change in autism symptoms is assessed with the SRS-A, which measures youngsters' ability to engage in reciprocal social behaviour in natural social settings, among all domains of autistic symptoms. The SRS-A consist of 5 subscales: 1) Social Awareness, 2) Social Cognition, 3) Social Communication 4) Social Motivation, and 5) Autistic Mannerisms. In total the five subscales comprise 65-items that are answered on a 4-point scale ranging from never true to almost always true. Completion of the questionnaire takes about 15 minutes. The SRS-A is completed by both parents and youngsters separately. Considering that SRS-A scores provided by youngsters are likely to be less reliable, the total score of the parents will serve as the primary outcome measure. In a secondary analysis, the total score of the youngsters will be used to determine the extent to which they perceive EMDR as an effective treatment.

Using the Autism Diagnostic Observation Schedule 2 (ADOS 2) changes in autism symptoms prior to and after treatment will be assessed. The ADOS is administered by observing the youngster during a semi-structured observation schedule. With the ADOS, the clinician elicits social, communicative, stereotyped and play behavior to observe symptoms of ASD. Activities are performed with a 40 to 60 minutes protocol. Observations of the clinician are categorized and a score is assigned for each domain of ASD symptoms. Total scores on the ADOS are compared pre-treatment and post-treatment.

Using the Trauma Symptom Investigation Form in Autism Spectrum Disorders (TIF-ASD) changes in autism symptoms prior to, during, and after treatment will be assessed. The TIF-ASD assesses the impact of traumatic events on five core symptoms of autism: 1) social and (verbal) communication skills; 2) behavioral problems; 3) stereotypical & ritualistic behaviors; 4) self-care skills; 5) vegetative symptoms. The total scale consists of 20 items which are completed by an observer (in our case the parents). Items are answered on a 5-point scale ranging from never to always. Completing all items takes about 5 minutes. The TIF-ASD is the only measurement, assessing the traumatic symptoms and behavioral aspects related to ASD due to traumatic events.

Youngsters' disease severity and global improvement will be assessed with the Clinical Global Impression Scales (CGI). To assess severity and afterwards improvement, both pre- and post-treatment assessments will be conducted. Assessment are conducted by a clinician who observes a youngster for about 15 minutes while interacting with others. Based on one's past experience with similar patients, the CGI-S enables a clinician to rate the severity of a patient's illness. Severity is assessed on a 7-point scale ranging from not at all ill to extremely ill. Opposed to the CGI-S, the CGI-I enables a clinician to assess the extent to which the severity of a patient's illness has improved or worsened relative to the baseline assessment. Improvement is assessed on a 7-point scale ranging from very much improved to very much worsened.