The estimate-and-subtract methodfor eliminating threats to validity is described. Yeaton
and Sechrest (1986, 1987b) argue that "no-difference"findings are fundamental to the
process of eliminating threats to validity. The estimate-and-subtract method, however,
eliminates a threat to validity without reliance on no-difference findings. This article
argues that eliminating a threat to validity using the estimate-and-subtract method often is
preferable to eliminating a threat to validity using no-difference findings. The article also
shows how to improve the use of no-difference findings in those instances where their use is
appropriate.
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