Which instrument’s MDC value shows 8.5 for PFPS and 12.2 for ACL, indicating differing pathology-specific MDCs?

Which instrument’s MDC value shows 8.5 for PFPS and 12.2 for ACL, indicating differing pathology-specific MDCs?

• A. AKPS
• B. KOOS-PF
• C. IKDC 2000
• D. ACL-RSI

Answer: (C)

Minimal Detectable Change reflects the smallest change that can be trusted as real rather than just measurement noise, and that threshold isn’t the same across different patient groups. The IKDC 2000 knee form is known to have pathology-specific MDCs, with different values depending on the population being assessed. In PFPS, the MDC is around 8.5, while in ACL populations it’s about 12.2, meaning a larger change is needed to be confident the improvement or decline is real in the ACL group. This difference arises because the amount of measurement error and the natural variability in scores differ between conditions, affecting the standard error of measurement and thus the MDC.

Minimal Detectable Change reflects the smallest change that can be trusted as real rather than just measurement noise, and that threshold isn’t the same across different patient groups. The IKDC 2000 knee form is known to have pathology-specific MDCs, with different values depending on the population being assessed. In PFPS, the MDC is around 8.5, while in ACL populations it’s about 12.2, meaning a larger change is needed to be confident the improvement or decline is real in the ACL group. This difference arises because the amount of measurement error and the natural variability in scores differ between conditions, affecting the standard error of measurement and thus the MDC.