Are ADI-R and ADOS-G Sufficiently Sensitive to Identify Rirbs Necessary to Meet the DSM-V Restricted Interest and Repetitive Behaviours Criteria?

Background:  Possible decrease of autism spectrum disorder (ASD) prevalence using DSM V, as compared to DSM-IV-TR, is diversely appreciated (30-40% -Matson, Hattier et al. 2012; Matson, Belva et al. 2012; 7%- Huerta et al. 2012; Mazefsky et al. 2012). A related question is how will DSM-V be operationalized in clinical settings. DSM-IV-TR criteria are most frequently operationalized using the Autism Diagnostic Observation Schedule-Generic (ADOS-G) (Lord et al. 2000) and the Autism Diagnostic Interview-Revised (ADI-R). Considering that the DSM-V will now require at least two different elements in the RIRBs domain rather than one like in the DSM-IV-TR (Http//DSM 5.org), it seems that the ADI-R and ADOS-G algorithm will retain autistic people with an insufficient number of RIRBs criteria to satisfy DSM-V criteria.

Objectives:  

1-       To evaluate the nature of RIRBs mostly identified by the ADI-R and the ADOS-G.  

2-       To evaluate the capacity of ADI-R and ADOS-G to detect the amount of RIRBs necessary to satisfy DSM-V ASD diagnosis.

Methods:  The first step consisted in mapping separately RIRBs items of the ADI-R and the ADOS-G  domains to the 4 symptoms of the DSM-V RIRBs area. This mapping was then applied to the ADI-R and ADOS-G scoring sheets of a sample of 70 children (age 15-72 months, X =44 mois) randomly selected from the Hôpital Rivière des Prairies database and scoring over the ADOS-G and the ADI-R cut-off off for autism. This allowed specifying qualitatively what are the RIRBs symptoms most frequently picked up by the two standardized instruments, and to determine if the autistic children above the third area algorithm in each of the two instruments were or not positive to the cut-off for this area in the DSM-V.

Results:  The RIRBs symptoms mostly detected by the ADI-R were repetitive use of objects (mean frequency= 1,1), followed by unusual sensory interests and unusual preoccupations (0,9), and mannerisms (0,8). The RIRBs mostly observed in the ADOS-G were excessive interest (1,5), followed by unusual sensory interest in play (1,3), and mannerisms (0,9). 8 (11,4%) children positive on ADI-R third area algorithm and 17 (24,3%) children positive on ADOS-G third area algorithm do not meet RIRBs cut off in the DSM-V criteria. The intersection of the children undetected by the combination of the two standardized instruments resulted in 5 (7,1%) subjects positive for the DSM-IV-TR criteria of the RIRBs domain, but which did not reach the DSM-V cut off in the RIRBs domain.

Conclusions:  These preliminary finding suggest that some autistic children diagnosed on the basis of the DSM-IV-TR will not meet the criteria of RIRBs domain of the DSM V. The next step of the present study will be to evaluate the frequency and the nature of RIRBs in a larger sample including wider age range and milder phenotypes and analyse the RIRBs separately according to the module of the ADOS and ADOS-2 (1, 2 and 3).