Design The study consisted of a development phase (see methods section describing development of ADAT-A), and a separate validation phase (reported in the results section of the current study). In the Development Phase: autistic adults completed two rounds of cognitive interviews (interview one n = 15; interview two n = 9); Development Survey One consisted of 251 autistic adults; Development Survey Two consisted of 448 autistic adults. The Validation Phase data reported in the results section of the current study consisted of 236 autistic adults.
Ethical Approval The research received a favourable ethical opinion from the relevant local Research Ethics Committees (ethics approval references P47603 and F1074), and was approved by the Coventry Autism Steering Group, who provided feedback on the cognitive interview schedule.
Participants The autistic group involved in the validation phase of the current study comprised 236 adults (87 male, 113 female, 33 non-binary, and 3 other gender, aged 18–61 years, mean age = 32.45, SD = 11.18) who self-reported a diagnosis of ASC from a trained clinician. Of these, 85 (36%) had an undergraduate degree and 58 (24.6%) a higher degree, 72 (30.5%) had a GCSE/A-level/College Diploma, 12 (5.1%) had no formal qualifications, and 9 (3.8%) preferred not to say; 50 (21.2%) participants were unemployed or unable to work. Participants were a community sample recruited from social media channels and the Autistica Network, a volunteers’ database in the UK where autistic people register to receive invitations to take part in research studies.
Measures
Development of the Autistic Depression Assessment Tool - Adult
The ADAT-A was developed through iterative stages with autistic adults:
Cognitive Interviews: The first stage involved identifying interpretation and response issues and missing autism specific items in a widely used and well validated depression assessment (PHQ-9) [30] with 15 autistic adults. Cognitive interviews ensure that the target population interpret and respond to questions as the researchers intend, a crucial part of establishing content validity for a tool [34]. A comprehensive set of pre-prepared prompts were developed to identify and clarify problems in interpreting the PHQ-9 questions with autistic adults (see supplementary information for full interview schedule). This interview schedule was developed from three community and public involvement (CPI) focus groups convened as part of a public engagement event which discussed how to adapt mental health assessment tools for autistic adults (none of whom took part in the cognitive interviews). Each focus group consisted of seven participants: one facilitator, and equal representation of autistic adults, clinicians and researchers in each group. Each focus group member was given a copy of the PHQ-9, and the facilitator asked the group to discuss any potential problems autistic adults may have in interpreting the questions, and how these could be addressed. Each facilitator compiled up to five key points which were subsequently presented to all attendees for further discussion in a plenary session, with any additional points noted by the plenary chair. A subsequent focus group was held with the Coventry Autism Steering Group, who further discussed the main points raised at the public engagement event and provided feedback on the researcher’s draft cognitive interview schedule. This ensured that the pre-prepared prompts were comprehensive, relevant and clear to autistic adults. Subsequently, 15 and 9 autistic adults took part in two rounds of cognitive interviews respectively to first identify potential issues in clarity, interpretation, and relevance of the PHQ-9 items, and second to test new and adapted items based on this feedback.
Online Development Surveys: Following the cognitive interviews, two online surveys were conducted to gather feedback on the PHQ-9 and further refine the ADAT-A with a larger sample of autistic adults. Development survey one consisted of 251 autistic adults who provided qualitative feedback and rated the clarity (yes/no) and importance (from 0 – 100) of each item of the PHQ-9 and adapted ADAT-A (234 diagnosed, 17 awaiting assessment; 30.7% male; mean age=41.91, SD=13.44; mean age of ASC diagnosis=36.09, SD=14.03; 61.4% Asperger Syndrome diagnosis). To ensure broad agreement for clarity/importance of individual items, retained items had to be rated at least 70/100 on clarity and importance. For those items rated below 70, the research team discussed the qualitative feedback and adapted the items to improve clarity. Development survey two asked autistic adults to complete and provide qualitative feedback on the PHQ-9 and revised ADAT-A (332 diagnosed, 117 awaiting assessment; 27.8% male; mean age=40.21, SD=13.25; mean age of ASC diagnosis=34.51, SD=14.28; 45% Asperger Syndrome/High Functioning Autism diagnosis). Subsequently, the research team met with an advisory group of 5 researchers, autistic people and those who support them, to address the qualitative feedback and finalise the ADAT-A items.
Autistic adults’ feedback was incorporated to ensure that the retained items in the ADAT-A were both clear and relevant to autistic adults’ experience of depression. Relevance of items were improved by: a) capturing change in behaviours from the individual person’s baseline, which could indicate depression, but overlap with common experiences of autistic people (e.g. “more difficulties with sleep than usual”); and b) by including additional autism specific indicators of depression (e.g. “If you mask or camouflage, finding it more difficult than usual to do so”). Items were clarified by removing abstract language, splitting up multiple different options within a question into separate questions, and increased use of relevant examples within items. Participants can also choose whether or not to see visual aids for each item to help quantify abstract response options (e.g. somewhat, very). It is recommended that these visual aids are optional, given that many but not all autistic people said they found these useful.
Autistic Depression Assessment Tool - Adult
The ADAT-A has 21 items capturing depression symptoms in the past 14 days. The ADAT-A has staged questions for each symptom: 1) the presence (yes/no) of the difficulty in the past 14 days; 2) if present, the length of time the difficulty has been experienced for over the past 14 days (from 1-3 to 12-14 days); and 3) the impact of the symptom on everyday functioning (from “Never” (0) to “Extremely” (4)). Answering “no” to a difficulty is scored 0, length of time is scored from 1-4, and impact from 1-4. Scores across the sections are summed to obtain individual item scores from 0-8, with total scores ranging from 0-168, with higher scores indicating a greater number / impact of depressive symptoms in the past 14 days.
A set of 13 items were designed with feedback from autistic adults to capture depression symptoms according to DSM-V and ICD-10 criteria (anhedonia, sleep difficulties, exhaustion, changes in appetite, depression, hopelessness, restlessness or slowing down, concentration difficulties, suicidality). An additional set of 8 items were also developed, informed from previous literature and autistic adults’ feedback. These additional items aimed to capture autism specific indicators of depression not currently included in previous depression measures (increased difficulties in social situations, increase in social withdrawal, increased difficulties in adapting to change, and increased sensory hyper-sensitivity).
The ADAT-A with complete scoring instructions is freely available from our group’s website: https://sites.google.com/view/mentalhealthinautism/resources/measurement-tools
Defeat and Entrapment Scale
The Defeat and Entrapment Scale (DES) [35] is a 16 item self-report scale designed to capture feelings of defeat (a failed social struggle), and entrapment (feeling as there is no escape route from one’s current circumstances). Participants rate statements such as “I want to get away from myself”, “I am in a situation I feel trapped in” (entrapment), and “I feel I have not made it in life”, “I feel that I am not a successful person” (defeat), on a five-point scale from 1 “Not at all like me” to 5 “Extremely like me”. The DES was developed and validated in a sample of university undergraduates and depressed patients, with evidence in support of factors capturing defeat and entrapment, excellent internal consistency for total scores and subscales, and convergent validity with related constructs (depression, hopelessness and social rank) [35]. However, the scale has not been validated in autistic adults. In the current study, Cronbach’s alpha showed excellent internal consistency for the DES total scale α=.955, defeat sub-scale α=.941, entrapment sub-scale α=.911.
Suicide Behaviours Questionnaire – Autism Spectrum Conditions
The SBQ-ASC is a self-report measure developed with and for autistic adults to capture suicidal thoughts and behaviours, based on extensive consultation through focus groups, cognitive interviews and online surveys with autistic adults [20]. The SBQ-ASC has 5 scored items. Item 1 assesses lifetime experience of suicidal thoughts and behaviours from “Never” (0) to “I have attempted to end my life” (4). Item 2 assesses frequency of intense suicidal thoughts in the last 12 months from “Never” (0) to “1 or more times a day” (6). Item 3 assesses perseverative intense suicidal thoughts from “Not Applicable” (0), “Less than 5 minutes” (1) to “More than 8 hours” (5). Item 4 assesses likelihood of suicide attempt from “Not Applicable” (0), “No chance at all” (1) to “Very likely” (5). A visual aid, such as a measuring jug or thermometer, is offered to participants to help quantify each response option for item 4 (e.g. “Very unlikely”, “Very likely”) if they think this could be useful to them. Item 5 assesses communication of future suicide intent and past suicide attempts to others. Responses are scored from “Not applicable” (0) / “No” (0), to “Yes, once” / “Yes more than once”. Endorsing either “Yes” item is scored 1 for suicidal thoughts, 2 for future suicide attempts, and 3 for past suicide attempts. Participants can endorse all the options giving a maximum score of 6 for item 5. Scores range from 0-26, with higher scores indicating higher levels of suicidal thoughts and behaviours. The SBQ-ASC has strong evidence in support of content validity, factor structure, internal consistency, test retest reliability, convergent and divergent validity in autistic adults [20]. In the current study, Cronbach’s alpha showed acceptable internal consistency for the SBQ-ASC total scale α=.671
Camouflaging Autistic Traits Questionnaire (CAT-Q)
The Camouflaging Autistic Traits Questionnaire (CAT-Q) is a 25-item self-report questionnaire assessing the extent to which a person engages in social camouflaging behaviours, validated in autistic and non-autistic adults with equivalent factor structure between the groups [27]. The CAT-Q captures three domains of social camouflaging: (1) “compensation” (behaviours used to compensate for autism-related difficulties in social situations); (2) “masking” (behaviours used to hide autistic characteristics or present a non-autistic personality to others); and (3) “assimilation” (behaviours used to fit in better with others and not “stand out” from the crowd). Participants rate each of the 25 questions on a seven-point Likert scale between “Strongly Agree” to “Strongly Disagree”. Responses are scored between 1 and 7, with higher scores for items which endorse presence of social camouflaging behaviour. In the current study, Cronbach’s alpha for whole scale α=.903, Compensation subscale α=.811, Masking subscale α=.663, Assimilation subscale α=.745.
Intolerance of Uncertainty Scale – Short Form
The Intolerance of Uncertainty Scale – Short Form (IUS-12) [36] is a 12-item self-report questionnaire capturing a form of anxiety, where a person tends to react negatively to uncertain situations. Participants rate statements such as “Unforeseen events upset me greatly”, and “When I am uncertain I can’t function very well”, on a scale from 1 “Not at all characteristic of me” to 5 “Entirely characteristic of me”. Scores range from 1-60, with higher scores indicating higher levels of intolerance of uncertainty. However, this scale although widely used in studies of autistic people, has not yet been validated in this group [37]. In the current study, Cronbach’s alpha showed excellent internal consistency for the IUS-12 total scale α=.87.
Demographics
Participants were asked to report on their age, gender, employment, highest qualification, and autism diagnosis.
Procedure
Participants were invited to complete an online survey, using Qualtrics, which aimed to better understand suicidality and mental health in autistic adults. Participants were informed that autistic adults 18-years or over could participate, regardless of experience of mental health problems or suicidal thoughts or behaviours. Participants were fully briefed about the nature of the research, that they could skip questions and sections of the survey that made them feel uncomfortable, stop the survey at any time and complete it later. Participants were also provided information about relevant support services before taking part in the study, after each section of the study, and after taking part in the study in a downloadable debrief sheet. After providing consent, participants completed the demographics questions, Camouflaging Autistic Traits Questionnaire (CAT-Q), Defeat and Entrapment Scale (DES), Intolerance of Uncertainty Scale – Short Form (IUS-12), Autistic Depression Assessment Tool – Adult (ADAT-A) and Suicide Behaviours Questionnaire – Autism Spectrum Conditions (SBQ-ASC). Subsequently participants were provided with a full debrief including information about further information and support, followed by a positive mood induction procedure (a doodle page with jokes, puzzles and cute animal videos) which has proved effective in previous research exploring similar topics [38].
Analyses
Analyses were conducted in SPSS version 26. 431 participants initially accessed the survey. Of these, 376 consented to take part in the study and 311 subsequently completed at least one measure. Of these 282 started the ADAT-A, and 236 (83.69%) completed the ADAT-A with no missing items. Visual inspection of the data showed no pattern to missing data. Where missing data accounted for less than 10% of the total number of items, missing items were imputed. No missing items were imputed for the ADAT-A as missing data for all 46 participants was >10% of the total number of items.
Exploratory Factor Analysis
Principle axis factoring analysis with Oblimin rotation was performed on the sample of 236 autistic adults who completed the ADAT-A. The sample size was sufficient for EFA, with over 7 participants per item, and over 100 participants total [29].
Reliability and Validity
Internal consistency was measured using Cronbach’s alpha for total scores. SBQ-ASC, defeat and entrapment are designed to measure rare experiences [20,32]. Therefore, as with previous similar research [11,20] Spearman’s correlations assessed convergent validity between the ADAT-A and measures of defeat, entrapment, and Suicidality (SBQ-ASC). Divergent validity was assessed using z-tests to compare the strength of the correlation coefficients. Specifically: a) whether the ADAT-A was significantly more strongly correlated with more proximal constructs (SBQ-ASC, defeat and entrapment) than more distally related constructs (CAT-Q, IUS-12); b) whether the autistic depression symptoms subscale of the ADAT-A was significantly more strongly correlated with an autism relevant construct (camouflaging autistic traits) compared to the cognitive/affective and somatic subscales of the ADAT-A; and c) whether the cognitive/affective subscale of the ADAT-A was significantly more strongly correlated with similar constructs capturing psychological distress (suicidality, defeat and entrapment), compared to the somatic and autistic depression subscales. Spearman r benchmarks for effect size: 0.1 = small effect, 0.3 = medium effect and 0.5 = large effect [39].