A Note About Null Events

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A Note About Null Events

The purpose of inserting null events in protocols is to fill the time intervals in which other groups are presenting treatments (and sometimes measurements and support events). This aligns the events in one group with events in another, thereby controlling for the effects of history. In some studies, instead of a null event, the event could be a placebo or other treatment. But, in this study, there is no deliberate treatment. In this sense it is a "time-slot holder. Nothing happens when the protocol is executed and a Null Event is encountered except that a screen with the words "Null Event" is displayed.