Time Last Known Well -Symptom Onset

What is the difference between Time Last Known Well and time of symptom onset?

The time last known well is the time the patient was last known to be without the signs and symptoms of the current stroke or at his or her prior baseline. When the onset of symptoms is clearly witnessed, then the time last known well is identical to the time of symptom onset. Under other circumstances, these terms are not synonymous.
Last updated on April 11, 2016
Manual: Advanced DSC - Acute Stroke Ready Hospital
Chapter: Performance Measurement DSPM

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