Age-related peers - Individuals who share the same age range.
Algorithm - A set of instructions or rules for performing a calculation or process to determine whether a
score on a diagnostic test or set of observations meets specific criteria necessary to assign a diagnosis.
Assessment for intervention planning - Careful examination of an individual’s strengths and challenges
across several domains of functioning with the express objective of directing treatment planning and
intervention based upon the person’s individual profile. An assessment for intervention planning expands upon
the diagnostic evaluation, capturing the child’s heterogeneity and individuality within the diagnostic category.
The desired outcome of the assessment process is an individualized profile that is incorporated into an
intervention plan. The intervention plan is designed to maximize child development and functional skills within
the context of the family and community environment. (Often referred to as “assessment” or “interdisciplinary
Care coordinator - The person who manages a caseload and who is responsible for ensuring that services
written in the Individual Family Service Plan and/or Individual Education Plan for an individual with a
developmental disability are provided.
Circumstantiality - A pattern of speech that is indirect and delayed in reaching its goal because of excessive
or irrelevant detail or parenthetical remarks. The speaker does not lose the point, but to the listener it seems
that the end will never be reached.
Comorbid disorder - A disorder that coexists with another diagnosis so that both share a primary focus of
clinical attention. Comorbidity may affect the ability of affected individuals to function and survive in a given
environment; it may be used as a prognostic indicator for treatment effectiveness and outcome.
Developmental disability - A severe and chronic impairment that is attributable to one of the following
conditions: mental retardation, cerebral palsy, epilepsy, autism or a disabling condition closely related to mental
retardation or requiring similar treatment. To establish eligibility for services within the regional center system,
a disability is further defined as having begun before the eighteenth birthday, as being expected to continue
indefinitely and as presenting a substantial adaptive impairment.
Developmental surveillance - An ongoing process of routine monitoring and tracking of children’s specific
developmental milestones during regular well child visits. The practice of developmental surveillance by health
care providers ensures early detection of developmental problems.
Diagnostic evaluation - The process of gathering information via interview, observation and specific testing
in order to arrive at categorical conclusions.
Differential diagnosis - Based on analysis of clinical data, the determination of which of two or more
disorders with similar symptoms is the disorder that is the primary focus of clinical attention.
Early identification - The prompt detection of developmental delays through medical and developmental
screening and at the youngest age possible. Such screening is provided to children school age or younger and
to their families who have or who are at risk of having a handicapping condition or other special need that may
affect their development. Early identification increases the chances for improving developmental skills.
Echolalia - A disorder of language that results in repetitions of words or phrases previously heard. Echolalic
responses can be immediate or delayed.
Ecological factor - The influence of interactions among people and their environments including the
social/emotional and physical environment. Ecological factors are studied in behavior settings, such as a family
and the environment within which it operates, in order to predict the effect a specific factor may have on a
Ecological validity - Skills or abilities authenticated and evidenced in natural and informal procedures, such as
a familiar setting at home or a casual conversation, that may not be similarly expressed in structured
assessment measures and tests.
Eye gaze - An individual’s eye contact with another individual or with an object. Eye contact is a nonverbal
form of communication and means of regulating social interaction. Observance of patterns of avoidance or
initiation of eye gaze is important in detecting a child’s capacity for sharing of attention and affect.
Family-centered - The procedure of assessing the child’s and family’s needs as a whole, i.e., allowing the
assessment to be family directed and designed to determine the resources, priorities and concerns of the
family. The outcome of a family-centered assessment is the identification of supports and services needed to
enhance the family’s capacity to meet the needs of the child.
High-functioning - A non-clinical description of a person with a diagnosis of autistic disorder who has
average or near-average intellectual ability. “High functioning” individuals with autism tend to achieve higher
levels of adaptive and communication skills. Also termed, “high functioning autism,” or “HFA,” it is not a
distinct diagnostic category.
Individuals with Disabilities Education Act (IDEA) - Public Law 105-17, amended in 1997, that ensures
that all children with disabilities have a free appropriate public education and related services that prepare them
for employment and independent living.
Interdisciplinary - The descriptor for the process of gathering information from a variety of disciplines
having unique knowledge of a particular aspect of the child and family, which stresses a highly coordinated
effort among the disciplines to complement (rather than duplicate) efforts and to forge information into a
cohesive plan for diagnostic conclusions and/or intervention.
Joint attention - The ability to share with another person the experience of an object of interest. Joint
attention generally emerges between 8 and 12 months of age. A moving toy, for example, typically elicits a
pointing behavior by the child, who looks alternately at the caregiver and the object.
Lead clinician - The professional who takes responsibility during an interdisciplinary team evaluation for
ensuring that all relevant evaluations are performed, documented and reported. The lead clinician is responsible
for assuring the integration of separate findings to formulate a diagnosis and/or assessment conclusions to
communicate the findings to the family and other team members.
Longitudinal assessment - Measurement across time of developmental progress, behavior and/or specific
symptomatology following treatment and/or intervention.
Longitudinal study - Research in which variables relating to an individual or group of individuals are assessed
over a period of time, such as a study of child development drawn from research data compiled from the same
group of children at different points in their lives.
Multi-disciplinary - In contrast to an interdisciplinary process, a process that proceeds as separate
evaluations by various professionals who often are affiliated with different entities (i.e., a university or
hospital), are rarely in close proximity and often operate without benefit of collaboration with other evaluating
professionals, consequently often drawing separate conclusions based upon their particular experience. A
multidisciplinary process can take one to two days, with the child and family participating in numerous
sessions, or it can take place over the course of several months.
Nonverbal IQ - A measure of intelligence that requires little or no language. Nonverbal tests of IQ measure
intellectual ability by requiring the examinee to manipulate objects, copy or draw. Examples of nonverbal
intelligence tests are the performance subtests of the Columbia Mental Maturity Scale, 3rd edition, Merrill-
Palmer Scale of Mental Tests, Leiter International Performance Scale and the Test of Nonverbal Intelligence,
Non verbal communication - Facial expressions, tone of voice, gesture, eye contact, spatial arrangements,
patterns of touch, expressive movement, cultural differences and other acts of expression involving no or
minimal use of spoken language. Research suggests that nonverbal communication is more important in
understanding human behavior than words alone and critical to social development and comprehension.
Norm-referenced assessment - Test scores, derived during the administration of a standardized test in its
developmental stage to a large sample of individuals within the same age range, which form the yardstick for
comparing a given individual’s score to a group average.
Phenotype - The visible properties of an organism that are produced by the interaction of the genotype and the
environment. In other words, the “phenotypic” expression of a disorder refers to the outward, behavioral
expression of symptoms that may or may not share a similar etiology, course or response to treatment.
Pragmatics - The analysis of language in terms of the situational context within which utterances are made,
including the knowledge and beliefs of the speaker and the relation between speaker and listener; the ability and
desire to communicate in an appropriate way for one’s age and culture.
Pre-verbal communication - Eye contact, gaze shifts, vocalizations and gestures that form the basis of
expression prior to spoken language development. Eye contact, gaze shifts, vocalizations and gestures are
examples of pre-verbal forms of communication.
Prosody - Prosody refers to the use of vocal stress and intonation to convey a meaning. For example, the only
difference between the noun ‘object and the verb ob’ject is that of stress placement. Intonation determines
whether the sentence “Mary’s eating cake” will be perceived as a statement (pitch falls on the last word) or a
question (pitch rises on the last word).
Psychometrics - The measurement of human characteristics such as intelligence, personality, etc. through the
administration of tests that are validated by objective and standardized scientific methods.
Receptive language - The act of understanding that which is said, written or signed.
Regional center - A statewide system of twenty-one locally based, state-funded, private nonprofit agencies
that provide diagnostic, case management and other services to individuals with developmental disabilities and
that help individuals and their families find and access those services.
Ritualistic behavior - Rigid routines, such as insistence on eating particular foods or driving to the store via
only one specific route when many options exist, or repetitive acts, such as hand flapping or finger
mannerisms (e.g., twisting, flicking movements of hands and fingers carried out near the face).
Screening - The use of a specific test or instrument to identify those children in the population most likely to
be at risk for a specified clinical disorder. The application of specific screening instruments for a particular
disorder may occur at a specific age for the general population or when concerns and/or results of routine
developmental surveillance indicate that a child is at risk for developmental difficulties. Screening instruments
are not intended to provide definitive diagnoses but rather, to suggest a need for further diagnostic evaluation
and assessment for intervention planning.
Social reciprocity - Mutual responsiveness in the context of interpersonal contact, such as awareness of and
ability to respond appropriately to other people. Social reciprocity is synonymous with inter-subjectivity.
Social referencing - An aspect of early social development whereby the infant or toddler uses the nonverbal
social cues (i.e., eye gaze, facial expression, tone of voice) of another to express or share excitement or
pleasure, or checks to see if a behavior will be affirmed or disapproved. The child with autism rarely, if ever,
gains social feedback through another’s tone of voice or facial expression.
Splinter skills - An isolated ability that often does not generalize across learning environments. These abilities
are often widely discrepant from other areas of functioning.
Stereotypic behavior - Repetitive movement of objects or repetitive and complex motor mannerisms including
hand or whole body movement such as clapping, finger flapping, wholebody rocking, dipping, swaying, finger
Structured interview - An interview that follows a fixed protocol for gathering information in which the
interviewer asks standard questions and codes the answers in accordance with predefined criteria.
Syndrome - A set of clinical signs or a series of behaviors occurring together that often point to a single
disorder or condition as the cause. In autistic disorder, a number of symptoms belong to the disorder, but a
variable subset of all the symptoms qualifies an individual for the disorder.
Tangentiality - Replying to a question in an oblique or irrelevant way.
Temperament - Characteristic behaviors, habitual inclinations or modes of emotional response in infants and
toddlers, which may persist and contribute to the development of personality in adulthood. Temperamental
behaviors are biologically rooted, commonly recognized as individual differences that appear early in
development and stable as observable behavior. Core temperamental characteristics are attentional persistence,
positive affectivity to people or objects, fearfulness, distress and irritability to novelty and frustration.