Conclusions We found patchy evidence on reliability and validity , for only a few of the tools used to measure behaviour problems in young children with ASD .
Background Behaviour problems are common in young children with autism spectrum disorder ( ASD ) .
There are many different tools used to measure behavior problems but little is known about their validity for the population .
Objectives To evaluate the measurement properties of behaviour problems tools  used in evaluation of intervention or observational research studies with children with ASD up to the age of six years .
The Behavior Problems Inventory: An Instrument for the Assessment of Self-Injury, Stereotyped Behavior, and Aggression/Destruction in Individuals with Developmental Disabilities
The Behavior Problems Inventory ( BPI-01 ) is a 52-item respondent-based behavior rating instrument for self-injurious , stereotypic , and aggressive/destructive behavior in mental retardation and other developmental disabilities . Items are rated on a frequency scale and a severity scale . The BPI-01 was administered by interviewing direct care staff of 432 r and omly selected residents from a developmental center between the ages of 14 to 91 years . For 73 % of those selected , at least one problem was endorsed on the BPI-01 . A total of 43 % showed self-injury , 54 % stereotyped behavior , and 38 % aggressive/destructive behavior . Confirmatory factor analysis and item-total correlations supported the three a priori factors . Analyses of variance ( ANOVA ) showed that of the variables age , sex , and level of mental retardation , only the latter had a significant effect on the BPI-01 total score , the SIB subscale score , and the Stereotyped Behavior subscale score . Aggression/destruction was not significantly related to any of the three variables . Individuals with a diagnosis of pervasive developmental disorder had higher scores on all three subscales than those without , whereas residents with a diagnosis of stereotyped movement disorder had higher Stereotyped Behavior scale scores than those without . The BPI-01 was found to be a reliable ( retest reliability , internal consistency , and between-interviewer-agreement ) and valid ( factor and criterion validity ) behavior rating instrument for problem behaviors in mental retardation and developmental disabilities with a variety of potentially useful applications . Strengths and limitations of the instrument are discussed
Conclusions We found patchy evidence on reliability and validity , for only a few of the tools used to measure behaviour problems in young children with ASD .
Background Behaviour problems are common in young children with autism spectrum disorder ( ASD ) .
There are many different tools used to measure behavior problems but little is known about their validity for the population .
Objectives To evaluate the measurement properties of behaviour problems tools  used in evaluation of intervention or observational research studies with children with ASD up to the age of six years .