Defining the Minimal Clinically Important Improvement,Substantial Clinical Benefit,and Patient Acceptable Symptom State for the iHOT-12,HOOS,and HOOS global in the Nonoperative Management of Nonarthritic Hip-Related Pain

Abstract

Background:

Score cutoffs of clinically important outcome values such as the minimal clinically important improvement (MCII), substantial clinical benefit (SCB), and Patient Acceptable Symptom State (PASS) are population and treatment specific. In patients with nonarthritic hip-related pain, numerous score cutoffs have been calculated for use after surgical treatment, but they have not been established for patients who pursue nonoperative care.

Purpose:

To determine the MCII, SCB, and PASS score cutoffs for the 12-item International Hip Outcome Tool (iHOT-12), the Hip Disability and Osteoarthritis Outcome Score (HOOS), and an 8-item abbreviated version of the HOOS (HOOS_global) among patients with nonarthritic hip-related pain who were managed nonoperatively.

Study Design:

Cohort study; Level of evidence, 4.

Methods:

The cohort included 15- to 40-year-old patients who were diagnosed with nonarthritic hip-related pain by a surgical or nonsurgical orthopaedic clinician and were advised to pursue nonoperative management at the time of evaluation. At baseline and 12-month follow-up, patients completed the iHOT-12, HOOS, and HOOS_global. Receiver operating characteristic curves were used to generate MCII, SCB, and PASS score cutoffs using an anchor-based approach as well as score changes between baseline and 12 months. The anchor question for the MCII and SCB utilized a 9-item global rating of change scale. The anchor question for the PASS was as follows (“yes”/“no” response): “Taking into account all the activities you have during your daily life, your level of pain, and also your functional impairment, do you consider that your current state is satisfactory?”

Results:

Among 61 patients (mean age, 28 ± 8 years; 50 [82%] female), for the iHOT-12, the MCII score cutoff was 14, the SCB score cutoff was 18, and the PASS score cutoff was 63. For the HOOS subscales, the MCII score cutoffs ranged from 4 (Activities of Daily Living) to 13 (Sport and Recreation), the SCB score cutoffs ranged from 10 (Symptoms and Activities of Daily Living) to 25 (Quality of Life), and the PASS score cutoffs ranged from 50 (Quality of Life) to 87 (Activities of Daily Living). For the HOOS_global, the MCII score cutoff was 5, the SCB score cutoff was 12, and the PASS score cutoff was 65. The models mostly had good responsiveness (area under the curve = 0.73-0.94).

Conclusion:

These clinically important outcome values can assist clinicians and researchers with interpreting patients’ clinical change during nonoperative treatment for nonarthritic hip-related pain.