An exploratory method for estimating the changing speed of epidemic waves from historical data. by Cliff, A, Haggett, P, Smallman-Raynor, M

“… BACKGROUND: Historical data are necessary to establish long-term trends in disease incidence but pose analytical problems since their accuracy and reliability may be poorly specified. METHODS: A robust measure of the spatial velocity, R(0A), of epidemic waves from space-time series is proposed using binary data. …”