OBJECTIVES

To enhance the intravenous immunoglobulin (IVIg) cost-effectiveness analysis (CEA) for idiopathic thrombocytopenic purpura (ITP) treatment, in order to generate a ranking through a multi-criteria decision analysis (MCDA) approach.

METHODS

The PROMÉTHÉE II MCDA method was applied to the IVIg CEA established by CADTH (2008). The analysis included IVIg (intervention) and observation (no treatment), Anti-D, methylprednisolone and prednisone (comparators) as the set of alternatives. The criteria set included the costs considered in the CEA analysis (treatment, hospital and intracranial hemorrhage [ICH] costs) as well as the main outcome (ICH avoided). A weight of 0.5 was considered for the cost and outcome criteria, respectively. This occurs because in incremental cost-effectiveness ratio calculation, total cost and total effectiveness represent 50% of the ratio, each one. PROMÉTHÉE II was applied to establish a classification level for each treatment from A (best level) to E (worst level). Dominant characteristic between treatments was also measured and denotes if one treatment outranks another in all criterion. PROMÉTHÉE II also established a panel, classifying each criterion as strong or weak point.

RESULTS :

Considering CEA results, PROMETHÉE II ranked the treatments from the best to the worst as the following: IVIg, Anti-D, prednisone, methylprednisolone and observation. IVIg, Anti-D, prednisone and methylprednisolone were classified as level B and observation was level D (dominated by all treatments). Despite the ranking position, IVIg, prednisone and methylprednisolone were dominant just over observation, while anti-D was dominant over prednisone and methylprednisolone. The criteria ICH avoided, ICH costs and hospital costs were classified as strong points for IVIg and Anti-D. Prednisone, observation criterion had treatment costs as strong point. All criteria were classified as strong point for methylprednisolone.

CONCLUSIONS

The CEA data were applied in a MCDA setting to contribute to the decision-making process. PROMÉTHÉE II generated a treatment ranking and other three outcomes to enhance CEA results.