A B C Cost A Cost B Outcome A Outcome B Cost-effectiveness ratio - PowerPoint PPT Presentation

R ESULTS PRESENTATION

O UTLINES Model transparency and validation (lecture 7) Deterministic results •Incremental cost‐effectiveness ratio (ICER) •Cost‐effectiveness plane and Efficiency frontier •Deterministic sensitivity analysis Probabilistic sensitivity analysis (PSA) •Presenting simulation on CE plane •Cost‐effectiveness acceptability curve (CEAC) •Cost‐effectiveness acceptability frontier (CEAF) Value of Information (VOI) (lecture 6) 139

E XPECTED RESULTS A B C … Cost A Cost B Outcome A Outcome B Cost-effectiveness ratio  Cost Cost i std  Outcomes Outcomes 140 i std

T YPES OF COST EFFECTIVENESS RATIOS (CER S )  Average cost-effectiveness ratios (ACERs)  Dispute about definitions  Treeage, dividing a therapy’s total costs by its total outcomes  Evaluate cost and outcomes of each intervention against its baseline option (e.g., “do nothing” or current practice).  Incremental cost-effectiveness ratios (ICERs)  Comparison of costs and outcomes among the alternative options  When there are only 2 options being evaluated, the average and incremental cost-effectiveness ratios are the same 141

E XAMPLE : A VERAGE RATIOS AND SIXTH STOOL G UAIAC TEST # Cost Cases Avg cost/case Guaiac detected detected * test 1 7.75 0.00659469 -- 2 10.77 0.00714424 5,495 3 13.02 0.00719004 8,852 4 14.81 0.00719385 11,783 5 16.31 0.00719417 14,279 6 17.63 0.00719420 16,480 *    C C 1 i    E E 1 i 142 Source: Neuhauser and Lewicki, NEJM, 1975;293:226‐8.

E XAMPLE : A VERAGE RATIOS AND SIXTH STOOL G UAIAC TEST # Cos Cases ACE Inc Incr. ICER Gua. t detected R* r. cases test cos t 1     7.75 0.00659469 2 10.77 0.00714424 5,495 3.02 0.00054955 5,495 3 13.02 0.00719004 8,852 2.25 0.00004580 49,127 4 14.81 0.00719385 11,783 1.79 0.00000381 469,816 5 16.31 0.00719417 14,279 1.50 0.00000032 4,687,500 *    6 17.63 0.00719420 16,480 1.32 0.00000003 44,000,000 C C 1 i    E E 1 i 143 Source: Neuhauser and Lewicki, NEJM, 1975;293:226‐8.

Example: Average ratios and screening methods of Type2 DM Rearrangement Method Cases Cost Incr. Incr. ICER Detected cases cost 1 7 160,733    3 9 166,477 2,872 2 5,744 Dominated (by 4 9 194,540 0 28,063 M3) 144 2 10 191,959 25,482 1 25,482 Dominated (by FPG 10 231,790 0 39,831 M2)

Cost‐effectiveness plane 145

Cost‐effectiveness plane and Efficiency frontier ICER = 25,500 ICER = 2,900 146

FRONTIER ( CHOOSING OPTIMAL OPTIONS ) 1. Rank options in ascending order of either outcomes or cost 2. Eliminate options that are strongly dominated (i.e. have increased cost and reduced outcomes compared with at least one other alternative) 3. Calculate ICERs for each adjacent pair of outcomes (e.g. between option 1 and 2, 2 and 3, 3 and 4, etc.) 4. Eliminate options that are weakly dominated (i.e. have less effective but higher cost‐effectiveness ratio than the next highest ranked option) 5. Recalculate the ICERs (e.g. between option 2 and 4) 6. Repeat step 4 and 5 if necessary 147

Example: Treatment options for Gastro‐Oesophageal Reflux Disease (GORD) Six treatment options  A: Intermittent proton-pump inhibitor (PPI)  B: Maintenance PPI  C: Maintenance H 2 receptor antagonists (H 2 RA)  D: Step-down maintenance prokinetic agent (PA)  E: Step-down maintenance H 2 RA  F: Step-down maintenance PPI 148 Source: Goeree et al., PharmacoEconomics, 1999; 16:679‐97.

S TEP 1: R ANK OPTIONS IN ASCENDING ORDER OF EITHER OUTCOMES OR COST Strategy 1-year cost Weeks with per patient GORD per ($) patient in 1 year C: Maintenance H 2 RA 657 10.41 A: Intermittent PPI 678 7.78 E: Step-down maintenance 748 6.17 H 2 RA D: Step-down maintenance PA 805 12.60 F: Step-down maintenance PPI 955 5.54 149 B: Maintenance PPI 1093 4.82

S TEP 2: E LIMINATE OPTIONS THAT ARE STRONGLY DOMINATED Strategy 1-year cost Weeks with per patient GORD per patient ($) in 1 year C: Maintenance H 2 RA 657 10.41 A: Intermittent PPI 678 7.78 E: Step-down maintenance H 2 RA 748 6.17 D: Step-down maintenance PA 805 12.60 Dominated by C, A, E F: Step-down maintenance PPI 955 5.54 150 B: Maintenance PPI 1093 4.82

Step 3: Calculate ICERs for each adjacent pair of outcomes Strategy 1-year cost Weeks Incr. Weeks ICER per patient with cost averted ($/GORD ($) GORD per ($) week patient averted) in 1 year C    657 10.41 A 678 7.78 21 2.63 8 E 748 6.17 70 1.61 44 F 955 5.54 207 0.63 329 B 1093 4.82 138 0.72 192 151

Step 4: Eliminate options that are weakly dominated Strategy 1-year cost Weeks Incr. Weeks ICER per patient with cost averted ($/GORD ($) GORD per ($) week patient averted) in 1 year C 657 10.41    A 678 7.78 21 2.63 8 E 70 748 6.17 1.61 44 F 955 5.54 207 0.63 329 F has less effective but higher ICER than B B 1093 4.82 138 0.72 192 152

Step 5: Recalculate the ICERs Strategy 1-year cost Weeks Incr. Weeks ICER per patient with cost averted ($/GORD ($) GORD per ($) week patient averted) in 1 year C 657 10.41    A 678 7.78 21 2.63 8 E 70 748 6.17 1.61 44 D 805 12.60 dominated F 955 5.54 dominated B 1093 4.82 345 1.35 256 153

Cost‐effectiveness plane and Efficiency frontier 154

All models have parameters uncertainty Deterministic sensitivity analysis • One‐way, multi‐way ― Showing how results depend on uni‐, multi‐ parameters ― Defensible range should be taken (e.g. SE, 95% CI) • Threshold analysis ― Identifying parameter’s value needed in order to change / still do not change the decision • Scenario analysis ― Several discrete values (e.g. risk group, acceptance rate, tool’s accuracy) have impact to the outcome, instead of a continuous range 155

One‐way sensitivity analysis Percentage change in ICER ranged from -65 to 30 when “Tornado diagram” showing the impact of utility of BT-ICT was varied from 0.3 to 0.9 uncertainty on the outcome of a decision model 156 Point estimate = 80,000 Source: Leelahavarong et al. BMC Health Services Research; 2010; 10:209.

ตัวอย่างของการใช้การประเมินทางเศรษฐศาสตร์ในการ ต่อรองราคายาในประเทศไทย กรณีวัคซีน HPV ราคาสูงสุดที่ยอมรับได้ กรณีไม่ต้องการลงทุนเพิ่ม ราคาวัคซีนต่อเข็ม (B REAK EVEN PRICE ) ( บาท ) 189 189 200 กระตุ้น 1 เข็ม 180 กระตุ้น 3 เข็ม 160 140 120 100 81 71 80 57 60 38 32 40 24 20 0 ฉีดซ้ําทุก 10 ป� ฉีดซ้ําทุก 15 ป� ฉีดซ้ําทุก 20 ป� ไม่ต้องฉีดซ้ํา * กรณีให้วัคซีนที่อายุ 15 ปี + คัดกรองทุก 5 ปีแก่สตรีอายุ 30-60 ปี ( ความครอบคลุม 70:70) เปรียบเทียบกับ 157 มาตรการพื้นฐานคือคัดกรอง VIA + PAP ทุก 5 ปีแก่สตรีอายุ 30-60 ปี ( ความครอบคลุม 80%)

T HRESHOLD ANALYSIS ICER 120,000 500,000 3 Rc=100,000 ฿/LYs C -5 5 158 -500,000

T HRESHOLD AT BREAK - EVEN POINT ( COST - SAVING ) ICER 120,000 500,000 3 Rc = 0 ฿/LYs C -5 5 159 -500,000

Threshold analysis Two‐way threshold analysis Three‐way threshold analysis 160 Source: Briggs AH, Weinstein MC, Fenwick EAL, et al. Model Parameter Estimation and Uncertainty: A Report of the ISPOR‐SMDM Modeling Good Research Practices Task Force‐6. Value Health 2012;15:835‐842.

F LASHBACK Cost‐Effectiveness Plane and ICERs 161

T HE COST - EFFECTIVENESS PLANE New treatment More costly - + Not take at all Existing treatment New treatment more effective Trade-off dominated But more costly New treatment New treatment C less effective More effective Trade-off Take all New treatment less costly New treatment But less effective dominated + - New treatment less costly 162

T HE COST - EFFECTIVENESS PLANE : ICER ICER 120,000 500,000 Rc=100,000 ฿/LYs 3 ICER 400,000 2 ICER -200,000 1 ICER 60,000 6 ICER 25,000 4 C -5 5 5 ICER -200,000 163 -500,000

T HE COST - EFFECTIVENESS PLANE : ICER ICER 120,000 500,000 Rc=100,000 ฿/LYs 3 ICER 400,000 2 ICER -200,000 1 ICER 60,000 6 ICER 25,000 4 C -5 5 5 ICER -200,000 Accept the technology if ICER < ceiling ratio 164 -500,000

V ALUE OF CEILING RATIO (R C )  Willingness to pay for one unit of outcome  Commonly unknown its true value  Depends on social value of health  May have more than one values at the same system!  Useful for producing cost-effectiveness acceptability curves 165

P RESENTING RESULTS FROM PROBABILISTIC MODELING 166