Validation of an uncertainty of illness scale adapted to use with Spanish emergency department patients and their accompanying relatives or friends.

Objectives: To validate a Spanish adaptation of the Mishel Uncertainty of Illness Scale for use with emergency-department (ED) patients and their accompanying relatives or friends (the UIS-ED).

Material And Methods: We first developed a version of the questionnaire for Spanish ED situations. Next we assessed the content validity index for each of its items, revised it, and reassessed its face validity to produce a second version, which we then piloted in 20 hospital ED patients.