A trend statistic and its variance were computed for each contingency table Trends were added up and variances were added up separately for the fatal tumor type and for the incidental one.The asymptotic probability that a trend was greater than or equal to the observed dose related trend, was computed separately for each context of observation.Afterwards, the fatal and incidental trends were summed, and their variances were summed too; and the overall asymptotic one-tailed probability for that tumor type was computed.Mathematical formula's had been given by Peto(ref. 1; pp. 386 - 388).Following Peto's advice(ref. 1, p. 402)the continuity correction was not applied.Not making this correction resulted in lowering the p-value and in increasing the risk of a false positive.When the asymptotic p-value was at least marginally statistically significant(p