MCID normalization: A methodological framework for harmonizing heterogeneous PROMs in hip arthroscopy research.

Area of Science:

• Orthopedic Surgery
• Clinical Research Methodology
• Biostatistics

Background:

• Hip arthroscopy (HAS) research utilizes numerous patient-reported outcome measures (PROMs), leading to heterogeneity.
• This diversity complicates cross-study comparisons and meta-analyses due to the absence of a gold-standard PROM.
• Existing methods lack guidance on integrating heterogeneous PROMs using the minimal clinically important difference (MCID).

Purpose of the Study:

• To investigate if heterogeneous PROMs in hip arthroscopy can be harmonized through MCID normalization.
• To develop and demonstrate a framework for standardizing diverse PROMs in HAS research.

Main Methods:

• Identified and ranked PROMs from 100 HAS studies based on frequency.
• Applied frequently reported MCID values from validation studies.
• Normalized PROMs by dividing observed values by MCID, creating a standardized metric in 'MCID units'.
• Utilized a proof-of-concept dataset with simulated studies for meta-analysis (REML).

Main Results:

• Identified 214 PROM mentions across 100 studies; modified Harris Hip Score (mHHS), iHOT-12, and HOS-SSS were most frequent.
• Normalization successfully transformed heterogeneous PROMs into a unified scale, enabling synthesis as 'number of clinically meaningful improvements'.
• The framework facilitated transparent, reproducible pooling of outcomes, preserving clinical interpretability.

Conclusions:

• MCID normalization offers a robust methodology to harmonize diverse PROMs in hip arthroscopy research.
• This approach enhances comparability, reduces bias in evidence synthesis, and supports meaningful interpretation of meta-analytic findings.
• The method translates heterogeneous PROMs into a unified, clinically interpretable metric, applicable to other surgical fields.