Tables and formulas for extended use of the Ederer-Myers-Mantel disease-clustering procedure.

The principles of the Ederer-Myers-Mantel procedure for seeking evidence of disease clustering are reviewed. The procedure is based on cumulative empirical clusters, i.e., the largest frequency in a single time period or in two successive time periods, and comparing that cumulation with the expected cumulation of largest frequencies under random occurrence. Original tabulations covered totals of up to 15 cases distributed among three, four or five time periods. Present tabulations of expectations and variances cover up to 500 cases distributed among two or three time periods and 200 cases distributed among four or five time periods. Asymptotic formulas are provided for the expectation and variance of the largest frequency in a single period when arbitrarily many cases are distributed at random among two, three, four or five time periods.