Julian C. Jamison†
Although the concept of randomized assignment in order to control for extraneous factors reaches back hundreds of years, the first known empirical use occurred in 1884 in an experiment on psychophysics by CS Peirce. Meanwhile, the first use of a control group in order to test the effect of an intervention occurred in medicine, informally in 1768 and then more carefully (but without randomization) in 1898. Remarkably, the combination of the two – a randomized control trial – was first instantiated in four different domains between 1924 and 1931, likely independently. These fields were agricultural science (with the celebrated contributions of RA Fisher); clinical medicine; educational psychology; and perhaps most surprisingly political science, in a voting experiment by HF Gosnell. Although this approach did not immediately become popular within social science broadly, there was a resurgence of interest in the 1950s and 1960s for both social policy experiments and formal laboratory experiments
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