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Table 2 Sensitivity analysis of the effect on the outcome of variation in model parameters

From: Modelling the potential impact of a sugar-sweetened beverage tax on stroke mortality, costs and health-adjusted life years in South Africa

Parameter tested Total stroke incidence over 20 years Total stroke DALYs over 20 years Total stroke prevalence over 20 years Total stroke health care costs over 20 years (billion ZAR)
Tax rate     
 10 % −50 457 321 750 −7 538 −3.0
 20 % −85 766 546 762 −12 860 −5.1
 30 % −109 435 706 570 −16 168 −6.6
Discount rate     
 0 % −85 766 546 762 −12 860 −5.1
 1 % −87 824 494 539 −13 165 −4.8
 2 % −88 646 441 074 −13 197 −4.3
 3 % −89 648 397 838 −13 300 −4.0
SSB portion size     
 200 ml −19 395 129 488 −2 760 −1.0
 250 ml −46 150 296 910 −6 882 −2.7
 330 ml −85 766 546 762 −12 860 −5.1
 500 ml −174 008 1 107 665 −26 115 −10.6
Health care costs     
 120 % −85 766 546 762 −12 860 −6.3
 110 % −85 766 546 762 −12 860 −6.0
 100 % −85 766 546 762 −12 860 −5.1
 90 % −85 766 546 762 −12 860 −4.8
 80 % −85 766 546 762 −12 860 −4.1
pYLD     
 100 % −85 766 546 762 −12 860 −5.1
 105 % −85 766 556 926 −12 860 −5.1
 110 % −85 766 541 548 −12 860 −5.1
BMI trend     
 0 −85 766 546 762 −12 860 −5.1
 0.1 −99 427 622 762 −15 432 −5.8
 0.2 −109 060 673 237 −17 269 −6.1
 0.3 −113 568 707 078 −18 015 −6.3
Pass on rate     
 80 % −74 637 477 949 −11 146 −4.5
 90 % −81 846 524 691 −12 198 −4.9
 100 % −85 766 546 762 −12 860 −5.1
Lower own price elasticity (−0.85) −32 205 211 543 −4 686 −1.8