“…Of the 42 articles included for analysis, 21 compared two or more incentive models to determine which one(s) were superior to the others. 18 , 19 , 23 , 28 , 29 , 31 , 34 , 37–50 Thirty-eight articles recommended a particular push incentive, pull incentive, or a push-pull hybrid model. 1 , 17 , 18 , 20–23 , 25 , 28 , 29 , 31 , 32 , 35–60 In terms of the four that did not make a recommendation, two of the studies simply reviewed different incentives and outlined possible benefits and disadvantages of each without offering a final recommendation, 19 , 34 one focused on analyzing the disadvantages associated with exclusivity extension pull strategies, 61 and the last paper did not support any push or pull financial incentives.…”