Physical functioning: self-report and performance measures are related but distinct.

Area of Science:

• Rehabilitation Medicine
• Clinical Assessment
• Pain Management

Background:

• Patients with chronic low back pain (CLBP) often report diminished physical functioning.
• Psychosocial factors like disability and mental health (MH) can influence self-reported physical functioning.
• The impact of these psychosocial factors on objective physical performance testing requires further investigation.

Purpose of the Study:

• To examine the correlation between the SF-36 physical functioning (PF) scale and physical performance via a modified treadmill test.
• To assess the influence of disability status and low MH scores on both self-reported physical functioning and physical performance in CLBP patients.

Main Methods:

• A cross-sectional study involving 63 CLBP patients.
• Participants completed the SF-36 questionnaire and underwent a maximal, symptom-limited, modified treadmill test.
• Treadmill walking time and heart rate were recorded; statistical analyses (unpaired Student's t-testing, effect size estimation) were used to determine the effects of disability and MH.

Main Results:

• A significant association was observed between the SF-36 PF scale and treadmill walking time.
• However, there was minimal overlap between the domains measured by self-report and physical performance.
• Disability status and low MH scores exerted a considerably greater influence on self-reported physical functioning compared to physical performance.

Conclusions:

• Self-report measures and performance-based assessments capture distinct yet related aspects of physical functioning.
• Lower SF-36 PF scores are linked to disability and poorer mental health in CLBP patients.
• Objective performance testing is crucial to supplement self-report measures for comprehensive assessment in CLBP management.