Development of a Modified Version of the Spinal Function Sort (M-SFS): A Mixed Method Approach

Area of Science:

• Rehabilitation Medicine
• Occupational Health
• Psychology

Background:

• Chronic low back pain significantly impacts work capacity and self-efficacy.
• Existing assessment tools may not fully capture work-related functional limitations.
• Self-efficacy beliefs are crucial for managing chronic pain and return-to-work.

Purpose of the Study:

• To modify the Spinal Function Sort (SFS) to better assess work-related self-efficacy in patients with chronic low back pain.
• To develop a shorter, more relevant version of the SFS for clinical application.

Main Methods:

• A mixed-methods approach combining semi-structured interviews, quantitative analysis of existing SFS data, and expert review.
• Interviews explored participants' experiences with SFS items and pain association.
• Quantitative analysis assessed internal consistency, unidimensionality, item response, and floor/ceiling effects.

Main Results:

• Eight new items were generated from interviews.
• Quantitative analysis indicated high internal consistency (Cronbach's alpha = 0.98) and supported unidimensionality.
• A floor effect was observed for items related to heavy material handling, and experts identified 8 relevant items.

Conclusions:

• A modified 20-item SFS was developed.
• The modified SFS aims to improve the assessment of work-related self-efficacy in chronic low back pain.
• Further validation studies are required to establish feasibility, reliability, and validity for clinical practice.