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Last Edited: 6/4/2001

What is a cancer cluster investigation?

A cluster study (most often a cancer study) is a descriptive study involving a review of an unusual number, real or perceived, of health events (for example, reports of cancer) grouped together in time and location. A cluster investigation can be used to confirm case reports and determine whether they represent an unusual disease occurrence. If enough information is known it may be possible to explore causes and environmental factors.