Table 4 Associations between incremental QALYs and covariates – DES vs BMSa
Bivariate | |||
|---|---|---|---|
∆ QALYs | |||
Covariates | β | N | se |
384 | |||
Population | |||
Age | 190 | ||
Age >75 | 0.029* | 1 | 0.002 |
Age 65-75 | 0.015* | 52 | 0.002 |
Age < 65 | ref | 137 | |
Complex lesion (yes vs. no) | 0.001* | 123 | <0.001 |
Complex vessel (yes vs. no) | 0.001* | 51 | <0.001 |
Multi vessel disease (yes vs. no) | 0.001 | 90 | <0.001 |
Diabetes (yes vs. no) | <0.001 | 135 | <0.001 |
Post MI (yes vs. no) | <0.001 | 25 | 0.001 |
Elective (yes vs. no) | −0.001* | 208 | <0.001 |
High risk (yes vs. no) | 0.004* | 127 | 0.001 |
Intervention | |||
Type DES | 384 | ||
Sirolimus eluting stent | 0.01 | 75 | 0.009 |
Paclitaxel eluting stent | 0.011 | 151 | 0.009 |
Zotarolimus eluting stent | 0.025 | 3 | 0.015 |
Drug eluting stent in general | ref | 155 | |
Study characteristics | |||
Country | 384 | ||
United Kingdom | 0.011 | 211 | 0.015 |
United States | 0.001 | 4 | 0.019 |
Canada | 0.016 | 72 | 0.015 |
Sweden | 0.002 | 39 | 0.019 |
Austria | 0.001 | 6 | 0.019 |
Finland | 0.005 | 1 | 0.019 |
Belgium | 51 | ||
Study year | 0.001 | 384 | 0.002 |
Horizon >1 year (yes vs. no) | 0.002 | 384 | 0.001 |
Horizon (months) b | <0.001* | 373 | <0.001 |
Type of study (CUA vs. CEA) | NA | NA | NA |
Model | 384 | ||
Markov model | 0.014 | 226 | 0.008 |
Discrete event simulation model | 0.001 | 6 | 0.014 |
Decision tree | ref | 152 | |
Perspective | 384 | ||
Health care provider perspective | 0.006 | 7 | 0.012 |
Health care sector perspective | NA | 0 | NA |
Non-public perspective | NA | 0 | NA |
Health care payer perspective | ref | 377 | |
Funding | 333 | ||
No | −0.001 | 30 | |
Yes | 303 | ||
Both Industry and No industry | 0.043* | 11 | 0.008 |
Industry | 0.012 | 42 | 0.006 |
No industry | ref | 250 | |
Discounting (yes vs. no)c | 0.015 | 90 | 0.013 |
Input parameters | |||
Number of stents used during the procedure | 0.001 | 379 | 0 |
Price difference between stents | NA | NA | NA |
Price of BMS stent | NA | NA | NA |
Price of DES stent | NA | NA | NA |
Costs of BMS procedure (incl. stents) | NA | NA | NA |
Costs of DES procedure (incl. stents) | NA | NA | NA |
Difference in procedure costs | NA | NA | NA |
Probability of restenosis BMS | 0.024* | 366 | 0.001 |
Probability of restenosis DES | 0.005 | 282 | 0.004 |
Relative risk reduction repeat revascularization | 0.007* | 300 | 0.001 |
Disutility of undergoing a CABG | −0.747* | 254 | 0.163 |
Disutility of undergoing a PCI | −0.107 | 254 | 0.433 |
Disutility of experiencing a MI | −0.021 | 40 | 0.097 |
Disutility for a patient with angina symptoms | −0.012 | 78 | 0.013 |
Quality of life of a patient with angina symptoms | −0.231* | 338 | 0.04 |
Quality of life of a patient after revascularization (recovered) | −0.24* | 380 | 0.024 |
Quality of life of a patient suffering from restenosis | −0.254* | 144 | 0.031 |
Assumptions | |||
Difference in clopidogrel (medication) usage (yes vs. no) | <0.001 | 270 | 0.001 |
Wait time for revascularization included (yes vs. no) | −0.012* | 336 | 0.006 |
Repeat revascularization is based on angiographic follow-up data (yes vs. no) | 0.013* | 329 | 0.006 |
DES and BMS are not mixed up during a procedure | 0.002 | 384 | 0.01 |
Repeat interventions that occur during time horizon are the result of restenosis | 0.02* | 384 | 0.01 |
There do not exist differences in mortality, thrombosis or MI between DES and BMS | −0.003 | 384 | 0.016 |
The type of repeat revascularization is the same for the DES and BMS treatment groups | −0.008 | 384 | 0.016 |
There does not exist a difference in survival between DES and BMS | 0.001 | 384 | 0.002 |
There does not exist a difference in thrombosis between DES and BMS | −0.003 | 384 | 0.016 |
There does not exist a difference in MI between DES and BMS | −0.006 | 384 | 0.01 |
Quality of studies (Philips et al. 2006) [7] | |||
Structure (%) | −0.006 | 384 | 0.033 |
Data (%) | 0.006 | 384 | 0.024 |
Consistency (%) | −0.018 | 384 | 0.02 |
Total (%) | <0.001 | 384 | 0.032 |