Enhancing the Short Physical Performance Battery: Proposing Norm Values for the 4-Meter Walking Test for Multimorbid...

Area of Science:

• Gerontology
• Rehabilitation Science
• Clinical Assessment

Background:

• The Short Physical Performance Battery (SPPB) is widely used to assess lower extremity function in older adults.
• Existing SPPB scoring presents floor effects in vulnerable, multimorbid populations, particularly the 4-meter walking test.
• This limits its utility in detecting subtle changes in physical functioning.

Purpose of the Study:

• To propose new norm values and a scoring system for the SPPB 4-meter walking test to address floor effects.
• To compare the sensitivity of the revised SPPB scoring system against the original system.
• To externally validate the proposed revised SPPB scoring system in independent cohorts.

Main Methods:

• Re-analysis of data from three randomized controlled trials (PROCARE, PROfit, PROGRESS) involving older adults.
• Development of new norm values and a scoring system based on quartiles of 4-meter walking test times from the PROCARE dataset.
• Evaluation of floor effects, sensitivity to change, and external validation using PROfit and PROGRESS datasets.

Main Results:

• The revised scoring system adjusted thresholds for performance categories, reducing the floor effect from 36% to 21%.
• The new system demonstrated improved sensitivity in detecting changes in walking test completion times.
• External validation confirmed that the revised scoring appropriately reflected participants' functional and cognitive characteristics.

Conclusions:

• The proposed revised SPPB scoring system effectively differentiates walking performance in multimorbid older adults, especially low performers.
• This enhanced scoring aids in detecting subtle performance changes missed by the original system.
• The revised SPPB scoring improves the assessment of physical functioning in vulnerable elderly populations.