title: Comparing Responsiveness of Six Common Patient-Reported Outcomes to Changes Following Autologous Chondrocyte Implantation: A Systematic Review and Meta-Analysis of Prospective Studies.
abstract: OBJECTIVE
  To compare the responsiveness of six common patient-reported outcomes (PROs) following autologous chondrocyte implantation (ACI).
  
  
  METHODS
  A systematic search was conducted to identify reports of PROs following ACI. Study quality was evaluated using the modified Coleman Methodology Score (mCMS). For each outcome score, pre- to postoperative paired Hedge's g effect sizes were calculated with 95% confidence intervals (CIs). Random effects meta-analyses were performed to provide a summary response for each PRO at time points (TP) I (<1 year), II (1 year to <2 years), III (2 years to <4 years), IV (≥4 years), and overall.
  
  
  RESULTS
  The mean mCMS for the 42 articles included was 50.9 ± 9.2. For all evaluated instruments, none of the mean effect size CIs encompassed zero. The International Knee Documentation Committee Subjective Knee Form (IKDC) had increasing responsiveness over time with TP-IV, demonstrating greater mean effect size [confidence interval] (1.78 [1.33, 2.24]) than TP-I (0.88 [0.69, 1.07]). The Knee Injury and Osteoarthritis Outcome Score-Sports and recreation subscale (KOOS-Sports) was more responsive at TP-III (1.76 [0.87, 2.64]) and TP-IV (0.98 [0.81, 1.15]) than TP-I (0.61 [0.44, 0.78]). Overall, the Medical Outcomes Study 36-Item Short Form Health Survey Physical Component Scale (0.60 [0.46, 0.74]) was least responsive. Both the Lysholm Scale (1.42 [1.14, 1.72]) and the IKDC (1.37 [1.13, 1.62]) appear more responsive than the KOOS-Sports (0.90 [0.73, 1.07]). All other KOOS subscales had overall effect sizes ranging from 0.90 (0.74, 1.22) (Symptoms) to 1.15 (0.76, 1.54) (Quality of Life).
  
  
  CONCLUSIONS
  All instruments were responsive to improvements in function following ACI. The Lysholm and IKDC were the most responsive instruments across time. IKDC and KOOS-Sports may be more responsive to long-term outcomes, especially among active individuals.
authors.affiliation: Division of Athletic Training, Department of Rehabilitation Sciences, University of Kentucky, Lexington, KY, USA ; Center for Cartilage Repair and Restoration, Department of Orthopaedic Surgery and Sports Medicine, University of Kentucky, Lexington, KY, USA.
authors.forename: Jennifer S
authors.initials: JS
authors.lastname: Howard
authors.affiliation: Center for Cartilage Repair and Restoration, Department of Orthopaedic Surgery and Sports Medicine, University of Kentucky, Lexington, KY, USA.
authors.forename: Christian
authors.initials: C
authors.lastname: Lattermann
authors.affiliation: School of Physical Therapy and Athletic Training, Old Dominion University, Norfolk, VA, USA.
authors.forename: Johanna M
authors.initials: JM
authors.lastname: Hoch
authors.affiliation: Division of Athletic Training, Department of Rehabilitation Sciences, University of Kentucky, Lexington, KY, USA.
authors.forename: Carl G
authors.initials: CG
authors.lastname: Mattacola
authors.affiliation: Division of Athletic Training, Department of Rehabilitation Sciences, University of Kentucky, Lexington, KY, USA.
authors.forename: Jennifer M
authors.initials: JM
authors.lastname: Medina McKeon
keywords: articular cartilage; cartilage; knee; outcomes assessment; self-report