Univariate Temporal Methods
At the present time, even a good surveillance system is perhaps best viewed as a “smoke detector.” They may pick up important public health diagnoses or syndromes, but only labor-intensive follow-up investigations will distinguish genuine fires from backyard barbecues.
Michael Grey and Kenneth Spaeth (2006, p. 76)
This chapter describes univariate temporal methods useful for early event detection (EED) and how to appropriately apply them to the biosurveillance problem. Biourveillance systems often apply variants of standard univariate statistical process control (SPC) methods – the Shewhart, cumulative sum (CUSUM), and exponentially weighted moving average (EWMA) methods – for EED. A challenge in applying these ...