Understanding the effects of extrinsic rewards on intrinsic motivation--uses and abuses of meta-analysis: comment on Deci, Koestner, and Ryan (1999)

Recently, 3 different meta-analytic reviews of the literature concerning the effects of extrinsic rewards on intrinsic motivation have appeared, including that by Deci, Koestner, and Ryan (1999) in this issue. Interestingly, despite their common focus, these reviews have offered dramatically opposed bottom-line conclusions about the meaning and implications of this literature. In this comment, the authors examine differences among these 3 reviews and conclude that the findings of this literature have been more accurately captured by the reviews of Deci et al. and Tang and Hall (1995) than by that of Cameron and Pierce (1994). More broadly, the authors also suggest that there may be significant short- and long-term costs to the unthinking or automatic use of meta-analysis with theoretically derived, procedurally diverse, and empirically complex literatures like that concerning extrinsic rewards and intrinsic motivation.