Objective: To determine the relative discriminant validity of 3 new versions of the Childhood Health Assessment Questionnaire (CHAQ) and to determine the relative concordance between children and their parents.
Methods: The parents of 48 children with musculoskeletal disability and 101 nondisabled controls were given the CHAQ and the 3 revised versions in random order. Children older than 5 years also completed the questionnaires.
Results: All 3 new versions of the CHAQ were more sensitive at differentiating patients from controls (relative efficiency 1.35-1.65); the versions with 8 added items were even more sensitive (relative efficiency 1.79-2.32). The new versions of the CHAQ suffered less from a ceiling effect and were more normally distributed. Concordance between children and parents was moderate to high for all versions.
Conclusion: Researchers and clinicians should consider using a revision of the CHAQ. By being more sensitive at differentiating patients, the revised versions of the CHAQ will allow fewer subjects to be studied and will be more able to detect differences between patients in the clinic.