Population-based normative values for the Western Ontario and McMaster (WOMAC) Osteoarthritis Index: part I.

OBJECTIVES

To develop population-based age- and gender-specific normative values for the pain, stiffness, and physical function subscales of the WOMAC Index for benchmarking applications.

METHODS

A scannable survey questionnaire capable of capturing WOMAC Index data and demographic information was developed, pretested, and distributed to a stratified random sample of 36,000 members of the Australian general public generated by the Australian Electoral Commission.

RESULTS

Age- and gender-specific WOMAC normative values were estimated based on approximately 7300 subjects. Age-related differences were noted in all 3 WOMAC subscales. In general, pain, stiffness, and difficulty with physical function percentiles increased with age.

CONCLUSIONS

WOMAC normative values provide opportunity for benchmarking the health status of individuals with hip and knee osteoarthritis against their age- and gender-matched peers in the general population. These normative values provide unique opportunities for using the WOMAC Index in benchmarking applications in both clinical practice and research.