Quality cost indicator: Reassessing the effects of health outcomes on healthcare expenditure. A retrospective cohort study

Abstract Background: Healthcare expenditure has increased rapidly over the last decades. Despite conceptual differences, healthcare expenditure and health outcomes play a significant role in Cost Effectiveness Analysis (CEA) and Value Based Health Care (VBHC). Better health outcomes can prevent additional costs to treat symptoms, adverse events and/or comorbidities. Therefore a partially inverse relationship between health outcomes and healthcare expenditure can be expected. Because it can be quite difficult to utilize this relationship to one’s benefit we developed a framework to model the relationship and tested it for breast cancer and bariatric surgery. Methods: The Quality Cost Indicator is calculated as QCI = 100 – average total costs / (resulting outcome ^2 * 100) and rests on three main measures. (1) Optimal outcome which is accomplished when patients meet all the defined health outcomes which differs per diagnoses/treatment; (2) Resulting outcome, the proportion of patients who accomplish optimal outcomes divided by the total patient population; (3) Average total costs, all costs related to the treatment including costs of AEs and comorbidities. Costs were determined using the Dutch cost price model. The Mann-Whitney U test was used to determine if costs of patients achieving optimal outcome were lower than costs of those who did not. Results: For the bariatric surgery population, 60.75% of patients reached optimal outcome excluding health related quality of life (HRQoL) and 60.74% including HRQoL. For breast cancer surgery 86.88% (excluding HRQoL) achieved optimal outcome. In the bariatric population (excluding HRQoL) and the Breast cancer population, patients achieving optimal outcome had significantly lower cost than those who didn’t. With € 8,442.48 vs. € 9,546.89 (p < .001) and €11,565.65 vs. € 16,119.56 (p < .001) respectively. For both populations QCI values were highest in 2020 Q4 as costs were average and optimal outcome was highest. Conclusions: The QCI framework is useful for modeling the partially inverse relationship between health outcomes and medical costs in bariatric and breast surgery. Future research should indicate if the QCI framework is applicable to other (non-surgical) treatments. Finally, comparing hospitals using the QCI framework could be helpful for comparing/optimizing health outcomes and costs.