Testing adults by questionnaire for social and communication disorders, including autism spectrum disorders, in an adult mental health service population

Abstract

Objectives Autism is difficult to identify in adults due to lack of validated self‐report questionnaires. We compared the effectiveness of the autism‐spectrum quotient (AQ) and the Ritvo autism–Asperger's diagnostic scale‐revised (RAADS‐R) questionnaires in adult mental health services in two English counties. Methods A subsample of adults who completed the AQ and RAADS‐R were invited to take part in an autism diagnostic observation schedule (ADOS Module 4) assessment with probability of selection weighted by scores on the questionnaires. Results There were 364 men and 374 women who consented to take part. Recorded diagnoses were most commonly mood disorders (44%) and mental and behavioural disorders due to alcohol/substance misuse (19%), and 4.8% (95% CI [2.9, 7.5]) were identified with autism (ADOS Module 4 10+). One had a pre‐existing diagnosis of autism; five (26%) had borderline personality disorders (all female) and three (17%) had mood disorders. The AQ and RAADS‐R had fair test accuracy (area under receiver operating characteristic [ROC] curve 0.77 and 0.79, respectively). AQ sensitivity was 0.79 (95% CI [0.54, 0.94]) and specificity was 0.77 (95% CI [0.65, 0.86]); RAADS‐R sensitivity was 0.75 (95% CI [0.48, 0.93]) and specificity was 0.71 (95% CI [0.60, 0.81]). Conclusions The AQ and RAADS‐R can guide decisions to refer adults in mental health services to autism diagnostic services.

The Effectiveness of RAADS-R as a Screening Tool for Adult ASD Populations

“…Whilst there is some support for the use of the RAADS-R in terms of test-retest reliability [ 25 ] and facilitating referrals in psychiatric and psychology services (albeit not in isolation) [ 26 ], as well as evidence of its ability to differentiate between ASD and eating disorder cohorts [ 27 ], other research supports what we have found here. For instance, Sizoo and Horwitz [ 17 ] examined the predictive validity of several assessments commonly used as screening tools in ASD clinical practice, including the AQ and RAADS-R.…”

“…This leads the authors to advice that the cutoff score of >65 is too low and should not be used. Alternatively, they recommend a higher threshold score of >120 [ 26 ]. Also, there is an argument that the RAADS-R is not a sensitive enough measure to detect milder variations of ASD.…”

“…We recognise that it is likely that the clinician would be able to respond to service user questions or elaborate more on the question details, which could have been reflected in the results. However, whilst this should be considered, a recent study found only 6% of patients were unable to complete the RAADS-R and AQ questionnaire by themselves and required assistance [ 26 ]. Further research would be required to investigate this possibility.…”

“…A particular strength of our study is that it was carried out in a setting that the RAADS-R assessment was intended for. As Brugha et al [ 26 ] allude, often studies that assess sensitivity and specificity are carried out in different populations. They compare people known to have the condition against control or general populations that are highly unlikely to have the condition, which leads to an overestimated validity of the assessment.…”

Study protocol: an investigation of the prevalence of autism among adults admitted to acute mental health wards: a cross-sectional pilot study

“…The study (also known as the SPRINT study (The Prevalence of S ocial Communication PR oblems in Adult Psychiatric In pa T ients)) will employ a multiple-phase cross-sectional design for participants without ID, and a single-phase design for participants with ID (figure 1). A multiple-phase approach to studying ASD prevalence has been used in several previous similar studies,12 19 39 as the ASD clinical interview-based diagnostic assessments are both time and resource intensive 40. Thus, a multiphase approach permits coverage of a larger study population per unit of resource.…”