“…There are 12 such studies, which we divide into a primary group of 5 (Fryer, 1941;Karpf, 1973;Roth, 1966;Walker, 1982;Wegner, cited in Merz, 1969) and a secondary group of 7 (Carroll & Payne, 1977;Dansereau, 1969;Dansereau & Gregg, 1966;Feldman, 1959;Johnson & Russo, 1978;Kazdin, 1976;Smead, Wilcox, & Wilkes, 1981). To the primary group we add Fidler (1983) and Schweiger (1983), which were not available to Ericsson and Simon. In the primary studies, the test for reactivity (and other aspects of protocol performance) was not an incidental check, but an important methodological goal.…”