Hawthorne effect

Professor Stephenopoulis finishes explaining his recent research but Professor Hawthorne has a comment.

Stephenopoulis: So that's what we found. A small experiment, only 8 patients, but basically all their insomnia was reduced after a nightly dose of 4 cashew nuts.

Hawthorne: Ineffable.

Stephenopoulis: Meaning?

Hawthorne: You only know what you know. You don't know what you don't know.

Stephenopoulis: I thought you were going to tell me that because it was a new treatment, it had a novelty effect and so everyone thought it was working.

Hawthorne: That's true too, or my name isn't Hawthorne. And even though I like small case studies, still I really would suggest more than 8 subjects, say a thousand, followed up longitudinally every year, before you could make any generalizations.

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