Criterion validity, reliability and clinical responsiveness of the CareConnections Functional Index

This study established the criterion validity, test-retest reliability and responsiveness of the CareConnections Functional Index (CCFI). The CCFI is composed of four body-region specific subscales, measuring functional ability. Reference standards included the Neck Disability Index; Modified Oswestry Disability Index; Quick Disabilities of the Arm, Shoulder and Hand and the Lower Extremity Functional Scale. One hundred subjects per body region were enrolled. Subject's rated their perceived improvement based on the 15-point Global Rating of Change questionnaire. Minimal clinically important differences (MCID) were calculated via receiver operator characteristic curve. Test-retest reliability coefficients were good to excellent. Validity correlations with the reference standard measures were acceptable (r > 0.7) for all subscales. MCID for the cervical subscale = 7 points, lumbar = 8 points, upper extremity = 16 points and lower extremity = 11 points. The results of this study support the use of the CCFI in outpatient physical therapy practice as a responsive tool with good reliability and validity. The results also indicate that future work should focus on the impact of baseline patient factors that may affect future outcome.