Functional disability was indicated by summated
parent- and child self-report of missed school and
missed family/friend activities. An alterative scale for
functional disability was considered that included the
total score for the Functional Disability Inventory (FDI).
However, the total score on the FDI was not strongly
compatible with missed school and missed family/friend
activities (Cronbach alpha=0.74); after removing the FDI
as an indicator variable, the reliability between missing
school and family/friend activities dramatically increased
(Cronbach’s alpha=0.93). Given that the missed school
and missed family/friend activities ask about the actual
amount of school and other activities missed, while the
FDI assesses more theoretically parent and child perceptions
of how difficult an activity would have been
to perform, this lack of clear concordance was not surprising.
Thus, we decided to test our model first on
report of actual behavior (i.e., missed school and missed family/friend activities), followed by testing
model replication using more general perceptions of
disability (i.e., FDI).