Interrater reliability of three clock drawing test scoring systems.

Area of Science:

• Neuroscience
• Clinical Psychology
• Rehabilitation Medicine

Background:

• The Clock Drawing Test (CDT) is a widely used neuropsychological tool.
• Assessing cognitive function in stroke patients requires reliable instruments.
• Standardized scoring is crucial for accurate interpretation of CDT performance.

Purpose of the Study:

• To evaluate the reliability of three established Clock Drawing Test (CDT) scoring systems.
• To determine interrater agreement and intrarater consistency of CDT scoring in stroke patients.
• To assess the applicability of CDT scoring systems across different CDT formats (freehand vs. predrawn).

Main Methods:

• Utilized 20 sets of Clock Drawing Tests (CDTs) from stroke patients undergoing rehabilitation.
• Employed three distinct, published CDT scoring systems for analysis.
• Two independent raters scored each CDT protocol.
• Measured interrater reliability and intrarater consistency using the intraclass correlation coefficient (ICC).

Main Results:

• High interrater reliability and intrarater consistency were observed across all three scoring systems.
• Scoring systems demonstrated comparable reliability for both freehand and predrawn circle CDT versions.
• Specific scoring components related to clockface contour showed slightly lower reliability coefficients.

Conclusions:

• The three evaluated Clock Drawing Test (CDT) scoring systems exhibit strong reliability for use with stroke patient data.
• These findings support the accurate and consistent application of the CDT in clinical stroke assessments.
• The CDT, when scored using these systems, is a dependable tool for evaluating cognitive function post-stroke.