Clinically Relevant Thresholds in Patient-Reported Outcomes: Do Patients' Expectations Evolve Over Long-term Follow-up?
Author(s): Walsh EG, McCarroll TR, Kuhns BD, Kahana-Rojkind AH, Quesada-Jimenez R, Domb BG
DOI: 10.1177/03635465251345823
Background
Interpreting patient-reported outcomes (PROs) after hip arthroscopy relies on clinically relevant thresholds such as the Minimal Clinically Important Difference (MCID), Patient Acceptable Symptom State (PASS), and Substantial Clinical Benefit (SCB). These thresholds provide context for understanding whether postoperative changes are meaningful to patients. However, little is known about how these thresholds—and the patients’ perception of improvement—evolve over long-term follow-up.
Methods
This retrospective study examined 414 hips that underwent primary hip arthroscopy between 2008 and 2021. Patients were included if they had complete PRO data at 2-, 5-, or 10-year follow-up, and were propensity score–matched to minimize confounding.
Clinically relevant thresholds for the modified Harris Hip Score (mHHS), Hip Outcome Score–Sports Specific Subscale (HOS-SSS), and International Hip Outcome Tool–12 (iHOT-12) were calculated using anchor-based methods to determine MCID, PASS, and SCB.
Key Findings
- Achievement of PASS and SCB increased with longer follow-up, particularly by 10 years postoperatively.
- PASS thresholds fluctuated over time, indicating changing perceptions of what constitutes an “acceptable” symptom state:
- mHHS PASS: 77.5 (2 yrs), 85.5 (5 yrs), 78.5 (10 yrs)
- HOS-SSS PASS: 82.7 → 76.4 → 67.7
- iHOT-12 PASS: 67.4 → 76.9 → 62.9
- SCB thresholds also varied, demonstrating evolution in what patients perceive as substantial clinical improvement:
- mHHS SCB: 95 (2 yrs), 99 (5 yrs), 88 (10 yrs)
- HOS-SSS SCB: 97 → 80.9 → 90.5
- iHOT-12 SCB: 89.4 → 94.1 → 82.5
- MCID values remained stable over time, and high percentages of patients met MCID at all intervals, suggesting durable improvement.
Conclusion
Long-term follow-up after hip arthroscopy reveals that while patients continue to achieve meaningful improvement, their expectations and thresholds for success may change over time. This suggests a potential recalibration in how patients interpret their outcomes and satisfaction, even as functional results remain strong.
What Does This Mean for Providers?
- Expect evolving patient perceptions: Over time, patients may redefine what they consider “acceptable” or “substantial” outcomes, which can influence how success is perceived.
- Outcome thresholds are dynamic: While MCID remains consistent, PASS and SCB vary over the years, highlighting the importance of contextualizing long-term PROs during follow-up.
- Tailor patient education: Providers should communicate that satisfaction and perceived benefit may increase over time, even if absolute functional scores plateau.
- Long-term value of hip arthroscopy: These findings support the durability of clinical benefit and underscore the importance of longitudinal monitoring and shared decision-making throughout recovery and beyond.