Nightmare Disorder Index (NDI)

The NDI was developed as a brief instrument to screen for DSM-5 nightmare disorder. The NDI can be scored in two ways: 1) as a continuous measure, representing severity of nightmare disorder symptoms, and 2) to categorize respondents as having no nightmare disorder, subthreshold/partial criteria met, or probable nightmare disorder. Detailed scoring information is provided along with the measure.

The paper describing development and initial validation of the NDI is available below.

Reference: Dietch, J. R., Taylor, D. J., Pruiksma, K., Wardle-Pinkston, S., Slavish, D. C., Messman, B., ... & Kelly, K. (2020). The Nightmare Disorder Index: development and initial validation in a sample of nurses. Sleep.

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