The MCID and PASS for the Modified Harris Hip Score and Hip Outcome Score Among Patient Undergoing

Surgical Treatment for FAI

Jaskarndip Chahal MD MSc FRCSC, Geoffrey S VanThiel MD MBA, Chad Mather MD MPH, Simon Lee MPH, Aileen M Davis PhD, Michael Salata MD, Shane J Nho MD MS

Department of Orthopaedic Surgery, Rush University Medical CenterMidwest Orthopaedics at Rush, Chicago, Illinois

Disclosures● Chad Mather: KNG Health Consulting; Pivot Medical; Smith & Nephew; Stryker; for[MD]; Arthroscopy

Association of North America; American Academy of Orthopaedic Surgeons; North Carolina Orthopaedic Association.

● Aileen Davis: Osteoarthritis and Cartilage.● Michael Salata: Linvatec; Smith & Nephew. ● Shane Nho: Stryker; Pivot Medical; Ossur; Arthrex Inc.; Linvatec; Smith & Nephew; DJ Orthopaedics;

Miomed; Athletico; Stryker; Pivot Medical; Allosource. Item 8: Journal of Bone and Joint Surgery.

Background: There is minimal information available for determining what constitutesa clinically significant difference in commonly used patient-reported outcomemeasures (PROMs) in patients treated with hip arthroscopy for femoroacetabularimpingement (FAI).

Purpose: To determine the minimal clinical important difference (MCID) and patientacceptable symptomatic state (PASS) for the modified Harris Hip Score (mHHS) andHip Outcome Score (HOS) in a population of patients with femoroacetabularimpingement treated with arthroscopic hip surgery.

Introduction

•Single center prospective cohort study in a consecutive series of patients with FAItreated with hip arthroscopic surgery.

•mHHS and HOS were administered at baseline and at 12 months post-operatively

•External anchor questions were administered at the 1 year follow-up to determineMCID (approach by Juniper et al.) and PASS (approach by Tubach et al.). The oneyear time-point was selected as this is felt to be the period when patient are mostlikely to achieve maximal improvement post-surgical intervention

Methods

•MCID and PASS were calculated using two methods:

•Receiver-operator curve (ROC) analysis: used to determine the cuff-off point whichoptimally defined the MCID and PASS based on sensitivity and specificity valuesfor each observed change score.

•The MCID and PASS were also calculated as the 75th percentile of the final mHHSscore or HOS subscale scores for patients who considered their state satisfactory.

•We also stratified the analysis according whether baseline scores influenced thelikelihood of achieving the MCID and PASS and odds ratios (OR) were calculated.

Methods

Optimal Scores Based on MCID

Results

MCID Grouping ROC Analysis 75th Percentile among group scoring +2 or

+3

+2 to +3 OptimalChange score

Cut off

Sensitivity Specificity

Mean (SD) Change score

HOS ADL 21.44 (15.90) 23.00 49.1 58.6 32.00

HOS SPORTS 31.88 (22.56) 47.00 82.1 28.9 44.74

mHHS 18.80 (11.19) 20.00 50.0 62.0 25.50

Optimal Scores Based on PASS

Results

PASS Grouping ROC Analysis 75th

Percentile among

PASS= yes group

No Yes OptimalFinal score

Cut off

Sensitivity SpecificityMean (SD)

scoreMean (SD)

score

HOS ADL 76.81 (12.95) 92.09 (7.15) 87.00 82.7 84.4 98.00

HOS SPORTS 54.24 (17.49) 83.26 (14.66)

75.00 79.6 96.9 94.00

mHHS 63.47 (10.65) 80.73 (7.04) 74.00 89.7 87.5 84.00

MCID and PASS after stratification based on baseline scores

Results

MCID PASSROC Analysis 75th

Percentile among group

scoring +2 or +3

ROC Analysis 75th

Percentile among group

scoring +2 or +3

OptimalChange

score Cut off

Sensitivity Specificity OptimalFinal Score

Sensitivity Specificity

Baseline scores in lower 50th percentileHOS ADL 36.00 83.3 40.0 50.50 84.00 82.4 90.0 95.00HOS SPORTS 53.29 72.7 50.0 62.26 73.00 72.2 95.2 87.75

mHHS 22.00 50.0 63.9 34.00 73.00 80.6 88.9 82.50Baseline scores in upper 50th percentileHOS ADL 5.00 81.4 27.3 26.00 87.00 83.1 85.7 98.00HOS SPORTS 16.00 70.6 47.1 30.00 72.22 89.7 90.0 91.67

mHHS 20.00 38.5 88.4 21.00 76.00 96.4 64.3 86.00

A Conceptual Illustration

The findings for the Hip Outcome Score in this study are used as an example.

Results

• 130 patients [mean age 35.6±11.7; 42.3% male]

• Receiver-operating curve analysis, the MCID for:

mHHS = 20.0

HOS (ADL) = 23.0

HOS (Sports) = 47

• Receiver-operating curve analysis, the MCID for :

mHHS = 74

HOS (ADL) = 75

HOS (Sport) = 87

Results

• Patients with higher baseline scores had smaller MCID values than thosewith lower baseline scores and were less likely to achieve the MCID 1-year following surgical intervention:

mHHS – OR 0.28

HOS(ADL) – OR 0.23

HOS(Sports) – OR 0.06

Results

• The PASS was not influenced by baseline scores yet patients with lowerbaseline scores were more likely achieve the PASS

mHHS – OR 3.36

HOS (ADL) – OR 3.83

HOS (Sports) – OR 3.38

• Age and sex were not significantly related to the odds of achieving theMCID or PASS for the mHHS or HOS.

Results

Conclusion

• This is the first study to determine the MCID and PASS for two commonlyused hip-joint PROMs in patients undergoing surgery for FAI.

• Baseline scores have been shown to influence MCID values and thelikelihood of achieving a given MCID or PASS in this patient population

• Our findings will allow researchers to determine if interventions related toFAI are meaningful to patients at the individual level across variousdomains and will also be useful for power calculations in futurerandomized trials related to hip arthroscopy and the treatment of FAI.

Conclusion

• Juniper EF, Guyatt GH, Willan A, Griffith LE. Determining a minimal important change in a disease-specific Quality of Life Questionnaire. J Clin Epidemiol. 1994;47(1):81-87.

• Tubach F, Ravaud P, Baron G, et al. Evaluation of clinically relevant changes in patient reported outcomes in knee and hip osteoarthritis: the minimal clinically important improvement. Ann Rheum Dis. 2005;64(1):29-33.

References