The Danish version of the modified Constant-Murley shoulder score: reliability, agreement, and construct validity

Area of Science:

• Orthopedics
• Physical Therapy
• Rehabilitation Medicine

Background:

• The modified Constant-Murley score (CMS) guidelines were updated in 2008.
• A Danish version of the modified CMS has been developed through translation and cross-cultural adaptation.
• The reliability and validity of this Danish version required formal assessment.

Purpose of the Study:

• To evaluate the test-retest reliability and agreement of the Danish modified Constant-Murley score (CMS).
• To assess the construct validity of the Danish modified CMS by comparing it with the Oxford shoulder score.
• To establish the clinical utility of the Danish modified CMS for patients with shoulder impingement syndrome.

Main Methods:

• A test-retest study design was employed.
• Forty-five patients with shoulder impingement syndrome were assessed by two experienced raters using the Danish modified CMS and the Oxford shoulder score.
• Intrarater and interrater reliability, agreement, and construct validity were analyzed.

Main Results:

• High intraclass correlation coefficients (ICCs) indicated excellent intrarater reliability (0.93-0.95) and interrater reliability (0.94).
• Minimal detectable change (MDC) values were 13 and 11 points for individual raters, and 12 points for interrater comparison.
• A strong positive correlation (0.76) was observed between the Danish modified CMS and the Oxford shoulder score, confirming construct validity.

Conclusions:

• The Danish version of the modified Constant-Murley score (CMS) exhibits acceptable intrarater and interrater reliability and agreement.
• The study confirmed the construct validity of the Danish modified CMS.
• This validated tool is suitable for assessing shoulder impingement syndrome in a Danish-speaking population.