A classical test theory evaluation of the Sleep Condition Indicator accounting for the ordinal nature of item response data.
Amanda HellströmPeter HagellAnders BroströmMartin UlanderAnnemarie I LuikColin A EspieKristofer ÅrestedtPublished in: PloS one (2019)
These observations support the integrity of the of the SCI. The SCI demonstrates sound CTT-based psychometric properties, supporting its use as an insomnia screening tool.