Responsiveness and Discriminant Validity of the Child and Adolescent Scale of Participation (CASP) for Children With Traumatic Brain Injury

RESEARCH QUESTIONS:

1. What is the responsiveness of Child and Adolescent Scale of Participation (CASP) scores among children and youth with traumatic brain injury (TBI) and a comparison group of children and youth with arm injuries across a 3-yr period?

2. What are the differences in CASP scores among children and youth with mild, moderate, and severe TBI and arm injuries across a 3-yr period?

RATIONALE: Participation in activities affects children's health and quality of life. Children and adolescents with TBI are often restricted in their participation due to the extent of impairments and social and physical environmental barriers. Thus, using reliable and valid instruments is essential for monitoring their recovery over time. The CASP was initially designed to assess participation of children and adolescents with TBI. This study examined the responsiveness and discriminant validity of the CASP in a large national (U.S.) sample of children with TBI across a 3-yr period.

DESIGN: Longitudinal prospective cohort

PARTICIPANTS: Five hundred fifteen children ages 0–18 yr with TBI (n = 401; classified as mild, moderate, or severe) and arm injury (comparison group, n = 114) from diverse racial and ethnic backgrounds.

METHOD: The CASP, which was designed to assess children's participation and restrictions in home, school, and community life compared with same-age peers, was administered at 3, 12, 24, and 36 mo postinjury.

ANALYSIS: Descriptive statistics were computed for all scores and demographic variables. Repeated-measures analysis of variance (within–between model) was used to examine differences among group scores over time along with Scheffé post hoc tests.

RESULTS: Comparison between four groups—arm and mild, moderate, and severe TBI groups—indicated a decrease in CASP scores from preinjury to 3 mo in all groups. A gradual increase in scores was found from 3 mo to 36 mo for the arm and mild and moderate TBI groups. However, in the severe TBI group, a gradual increase was found from 3 mo to 24 mo, but a decrease in scores was found from 24 mo to 36 mo.

Scores at 36 mo were found to be higher than preinjury for the arm and mild TBI groups, but lower for the moderate and severe TBI groups. A significant time effect was found between groups (F = 13.066, p < .001), as well as interaction effect between time and type of group (F = 2.306, p = 0.014). The severe TBI scores were found to be significantly lower than scores from the other groups. The arm injury scores were found to be consistently higher than all the TBI scores across time.

DISCUSSION: Results provide evidence of the CASP’s responsiveness to change over time particularly for the severe TBI group. The results indicated a pattern of gradual increase in CASP scores over time for most groups. Groups with low level of severity (arm and mild TBI), on average, displayed improved CASP scores and returned to their preinjury level or slightly higher at 36 mo postinjury. Groups with high level of severity (moderate and severe TBI), however, did not return to their preinjury level at 36 mo postinjury.

Consistent with prior discriminant validity evidence, the CASP was able to differentiate children with more severe injuries from those with milder injuries. These results support the use of the CASP for assessing participation of children with TBI across levels of severity and time.

IMPACT STATEMENT: Promoting meaningful participation is the ultimate aim of occupational therapy. The results contribute to the current psychometric evidence of the CASP and support its use to assess participation of children with TBI over time. This evidence is important to consider when selecting measures for use in research and practice.