Considerations for Clock Drawing Scoring Systems in Perioperative Anesthesia Settings.

The Clock Drawing Test is a cognitive screening tool gaining popularity in the perioperative setting. We compared 3 common scoring systems: (1) the Montreal Cognitive Assessment; (2) the Mini-Cog; and (3) the Libon scale. Three novice raters acquired interrater and intrarater reliability for each scoring system and then scored 738 preoperative clock drawings with each scoring system.