AGRE is now using the following 3 computer-scored affected status categories: "Autism," "Not Quite Autism (NQA),” and "Broad Spectrum," which are based on the Autism Diagnostic Interview – Revised (ADI-R) domain scores. We provide these categorizations not to limit analyses or impose them upon researchers, but to facilitate analysis by those who may not be comfortable interpreting the ADI-R data to formulate their own diagnoses. Please note, however, that the raw ADI-R scores are also available, permitting additional classifications that a particular investigator may deem appropriate.

It should be understood that while AGRE uses ADI-R data to derive these affected status categories, the authors of the ADI-R (Rutter, Lord, LeCouteur, 1997) have provided a validated algorithm (based on DSM-IV criteria) solely for a diagnosis of autism. There are, therefore, no validated ADI-R algorithms available to identify individuals on the broader autism spectrum (e.g., PDD-NOS, Asperger's or other broader phenotypes). As a result, many research groups utilize the ADI-R in combination with other diagnostic instruments, such as the ADOS, to derive clinical diagnoses of PDD-NOS and Asperger's.

In recognizing that there are many different ways to approach diagnostic algorithms, AGRE has provided the full ADI-R data so that individual investigators can apply their own criteria (http://www.agre.org/program/aboutadi.cfm). In addition, we have provided ADOS scores and other clinical data for many of our participants, so that researchers may consider these data when clarifying diagnoses along the autism spectrum (http://www.agre.org/program/aboutadosg.cfm).

Because AGRE recognizes that some researchers prefer to have affected status categories pre-assigned, AGRE has provided such classifications for the AGRE sample. In addition to providing strict autism diagnoses, AGRE has assigned the affected status classifications of NQA and Broad Spectrum so that researchers can easily identify family members on the spectrum who show potential value for inclusion in genetic or behavioral studies of autism. Please note that these latter two categories are not DSM-IV diagnoses, but rather, diagnostic classifications that would require further clinical analysis in order to establish a diagnosis based on DSM-IV criteria. The following is a summary of AGRE's current diagnostic categories:

1. Autism is identified using the well-validated ADI-R scoring algorithm (Rutter, Lord, LeCouteur, 1997).

2. NQA (Not Quite Autism) represents individuals who are no more than one
point away from meeting autism criteria on any or all of the 3 "content" domains (i.e., social, communication, and/or behavior), and meet criteria on the “age of onset” domain; or, individuals who meet criteria on all 3 "content" domains, but do not meet criteria on the "age of onset" domain.

3. Broad Spectrum defines individuals who show patterns of impairment along the spectrum of pervasive developmental disorders. This is a broad diagnostic category that encompasses individuals ranging from mildly- to severely-impaired. This category potentially includes such pervasive developmental disorders as PDD-NOS and Asperger's syndrome, which are used in many genome scans; however, this classification is not based on any validated algorithms.

PLEASE NOTE: Because a number of the subjects included in the Broad Spectrum category have relatively low domain scores and may not meet the diagnostic criteria for an autism spectrum disorder, we recommend that researchers take a close look at the domain scores of each subject (along with the ADOS results, if available), before deciding whether or not to include them in their subject pool.

AGRE AFFECTED STATUS ALGORITHMS

Code

Note: All of the following algorithms are based on ADI-R domain scores.

I. "AUTISM" classification:
Uses the well-validated ADI-R diagnostic algorithm (Rutter, Lord, LeCouteur, 1997):

1. social >= 10, and
2. communication: verbal >= 8; nonverbal >= 7, and
3. behavior >= 3
PLUS age of onset >= 1

II. "NOT QUITE AUTISM (NQA)" classification:

EITHER:

(A) Meets cut-offs on all 3 "content" domains, but not age of onset domain:
1. social >= 10, and
2. communication: verbal >= 8; nonverbal >= 7, and
3. behavior >= 3
PLUS age of onset = 0

OR:

(B) Is no more than 1 point below cut-off on any, or all, of the 3 "content" domains, and meets “age of onset” domain:
1. social >= 9, and
2. communication: verbal >= 7; nonverbal >= 6, and
3. behavior >= 2
PLUS age of onset >=1

III. "BROAD SPECTRUM" classification:

Age of onset >= 0;
PLUS does not meet criteria for Autism or NQA;
PLUS meets one or more of the following (A, B, or C):

(A) Shows severe deficit on at least one domain; severe is defined by scores at one or more of the following levels (e.g., 1 or 2 or 3):
1. social >= 8, or
2. communication: verbal >= 7; nonverbal >= 6, or
3. behavior >= 3

(B) Shows more moderate deficits in at least two domains; moderate is defined by scores at two or more of the following levels (e.g., 1 + 2, or 2 + 3, or 1 +3):
1. social >= 4
2. communication >= 3 (nonverbal or verbal)
3. behavior >= 2

(C) Shows only minimal deficits, but in all three domains at the following levels:
1. social >= 3, and
2. communication >= 2 (nonverbal or verbal), and
3. behavior >= 1