French validation of the Foot Function Index (FFI)

Area of Science:

• Rheumatology
• Orthopedics
• Health Outcomes Research

Background:

• Rheumatoid arthritis commonly affects the feet, leading to pain, disability, and restricted activities.
• Accurate assessment tools are crucial for managing rheumatoid foot conditions.

Purpose of the Study:

• To validate the Foot Function Index (FFI) for French-speaking populations.
• To establish the FFI's reliability and validity in evaluating rheumatoid foot conditions.

Main Methods:

• Cultural adaptation and translation of the FFI into French (FFI-F).
• Prospective validation involving 53 rheumatoid arthritis patients.
• Statistical analysis of acceptability, internal consistency, reproducibility, validity, and responsiveness.

Main Results:

• The FFI-F demonstrated high internal consistency (Cronbach's alpha 0.85–0.97).
• Good test-retest reproducibility (correlation coefficients > 0.56) and external validity were observed.
• The FFI-F proved to be a responsive measure for change.

Conclusions:

• The FFI-F is a culturally acceptable and valid tool for evaluating the rheumatoid foot in French patients.
• This validated instrument can be utilized in routine clinical practice and research.
• The FFI-F may also be applicable to other conditions causing foot-related functional impairments.