Abstract
A goodness of fit test statistic for the univariate logistic response model proposed by Prentice (1976) for quantal response bioassays is described and extended to the multiple regressor. variable situation. The size and power characteristics of the test statistic was found to be adequately described by a chi square variate for sample sizes as small as SO and its power was found to be dependent upon both the sample size and the true underlying response model.