SUMMARY OF THE RESEARCH OF IVAR LOVAAS
Since the early 1960’s, Dr. Ivar Lovaas and his associates have conducted research on behavioral
interventions for people with autism. In the beginning, in order to more objectively measure the
effect of various environmental interventions, the syndrome of autism was broken down into
separate behavioral components (Lovaas, Freitag, Gold, & Kassorls, 1965). Seven behavioral delays
were identified: language, motivation, imitation, toy play, peer play, self-help skills, and cognitive
functioning. Two behavioral excesses were also noted: self-injury and aggression against others,
and ritualistic behaviors such as hand flapping. Delays and excesses were then examined separately
with children diagnosed with autism by independent clinicians using then current nosological
systems (presently DSM-IV). Environmental variables were selected from laboratory research in
learning theory, especially work on reinforcement, shaping and discrimination learning. In most
studies, a small number of children were studied intensively, and single-subject experimental
designs (Barlow & Herson, 1984) were used to control for potential confounds.
This research contributed to a number of experimentally validated procedures for reducing certain
behavioral excesses displayed by individuals with autism, as well as helping them to overcome
behavioral delays (Schreibman, 1988). These procedures, and those developed by other
investigators using similar methodologies, form the basis for the intensive behavioral treatment that
is referred to as the Lovaas or ABA method.
Two important studies from the UCLA Clinic have become research classics (Lovaas, Berberich,
Perloff, & Schaffer, 1966; Lovaas & Simmons, 1969). Most of this research has been replicated and
extended by independent investigators (see, for example, a review by Lovaas, Koegel, and
Schreibman, 1979). Many of the procedures have become standards in behavioral treatment
programs for children with autism (Newsom & Rincover, 1989; Schreibman, 1988). In 1973, Lovaas,
Koegel, Simmons and Long published the first long-term follow-up study on the behavioral
treatment of children with autism. Positive findings showed that all children improved; the longer
treatment lasted the more improvement was made; complex behaviors such as language could be
acquired; and maladaptive behaviors, such as self-injury, could be decreased. Negative findings
were that no child achieved normal functioning; no child developed social interactions or play with
other children; children regressed after treatment ceased; and treatment gains did not generalize
across environments, or across behaviors that were not a focus of treatment. The findings from the
1973 study were consistent with other experimental reports in the literature (DeMyer et al., 1981;
Rutter, 1985, Smith, 1983).
The negative findings from the 1973 study strongly influenced the design of the next treatment
program, the UCLA Young Autism Project, which ran from 1970 to 1984 (Lovaas, 1987). In an
attempt to increase treatment effectiveness, four changes were made. First, treatment was
concentrated on young children with autism (average age at intake was 34 months).
It was reasoned that younger children would need less time to catch up to their peers because their
maladaptive behaviors might be less excessive and disruptive and the younger child’s nervous
system might be better able to assimilate new behaviors (Huttenlocher, 1984). Second, the 1987
study treated children in their homes, included training the parents, taught peer play, and helped
mainstream children into normal preschool environments in an attempt to facilitate further growth.
Third, the 1987 study treated the children for two or more years, with 40 hours or more per week of
1:1 behavioral intervention. This was done to more closely approximate the opportunities that are
available to average children, who appear to learn from the environment most of their waking
hours. Fourth, specific behaviors were targeted in all relevant environments, such as home,
preschool, and neighborhood, to assist in generalizing skills.
The 1987 study employed an experimental-control group design. Children were assigned to either
an experimental group, totaling 19 children, who received intensive treatment, or a control group,
totaling 19 children who received much less intensive treatment. The assignment was based on
availability of therapists to provide intensive treatment. If therapists were available, a child entered
the experimental group; otherwise the child entered the control group. A matched pair random
assignment procedure had initially been proposed, but parents objected to such a procedure, so the
therapist availability model was adopted. Nineteen diverse pre-treatment variables showed the
experimental and control groups to be comparable at intake. An additional control group of 21
children was also employed which consisted of children who were seen by an independent agency,
rather than by Dr. Lovaas, and were matched on pre-treatment variables to the experimental group.
After treatment, children in the experimental group had higher IQ scores, averaging 83 versus a pre-
treatment average of 60. They also required less restrictive school placements than children in the
control groups. Nine experimental children, which Lovaas termed “best outcome” children (47%),
attained scores within the average range of intellectual and educational functioning by 7 years of
age. (IQ averaged 107 and all were in regular classes without help).
In contrast, only 1 of 40 in the two control groups (2.5%) achieved such a favorable outcome, a
finding consistent with the results reported by others (Rutter, 1985). Follow-up assessment of these
children when they averaged 11.5 years of age, by McEachin, Smith & Lovaas (1993), found that the
experimental group had maintained their gains over the control group. Evidence of this consisted of
less restrictive school placements, greater levels of adaptive behavior, and maintenance of IQ scores
30 points higher than the control group children. The nine best-outcome experimental children
received particularly extensive evaluations using a double blind psychological interview. Eight of the
nine best-outcome children were found to be indistinguishable from normal children on the tests
The best outcome children from the 1987 study have been followed into early adulthood. Of the
nine best outcome children, seven had been evaluated at an average age of 24 years. The
evaluation included an intelligence test, personality test, and tests of abstract thinking. Results
showed that they maintained their IQ gains so that the average IQ was 108 compared to 107 at age
seven, and 109 at age 12. They showed superior performance on a concept formation task, they
had normal personality profiles on the MMPI and Rorschach, and they were able to demonstrate
abstract thinking in theory of mind tasks. In terms of their independent functioning, four had gone
to college, one had graduated from high school, and one had not graduated. Three had regular jobs,
one was self-employed, one was still in college and one was unemployed. Four lived independently,
and two were still at home. These latter two were both college students. Five had driver’s licenses
and four managed their own finances.
The other two were the ones who were at home going to college. All said that they had close
friends. In terms of problems with peers, two felt that they had problems with their temper, one
felt that he had a problem of being shy, and three said they had no problems at all. In terms of
intimate relationships, one was married, three had current boyfriends or girlfriends, one had a
girlfriend or boyfriend in the past, two had no current boyfriend or girlfriend, and all of them
wanted to get married. To summarize, the best outcome children seemed to have maintained their
gains into adulthood, they had normal intellectual and neuro-psychological functioning, they did not
display clinically significant abnormal behavior on assessments that were given, and all had
considerable independence and close relationships. (Smith, Wynn, & Lovaas, 1996)
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