Analyzing the effect of HTA systems on health outcomes
In the past half-century, the developed world has made remarkable progress in improving its citizen’s well-being and health. The innovation and use of new technologies is one of the bigger driving forces behind health improvement. Governments have created Health Technology Assessment (HTA) systems that review such technologies, in hopes of avoiding processes and practices that are obsolete or ineffective and of boosting technologies that are useful and cost-efficient. This article attempts to see if there is a correlation between the introduction of HTA systems and improvement in health outcomes.
We selected members of the Organization for Economic Co-operation and Development (OECD), and then filtered out countries that joined after 1980 and those that did not have HTA systems in place. Though many countries outside the OECD also have HTAs in place, we used OECD countries as a proxy for homogeneity in economic development. We searched for countries with HTA systems through desktop research using publicly available information about government organizations and identifying fourteen OECD countries with HTA bodies.
We analyzed three separate health outcomes, all of which were sourced from the World Bank Data Centre. We included mortality rate, life expectancy at birth and infant mortality rate. We took each of the metrics and determined the percentage change of the rate, either increasing or decreasing, year over year, from 1981-2011.
For the countries with HTA systems, we then pooled the data and took the average percent change over time in the years prior to the establishment of HTA system and then the average in the years following. We recorded the difference, using it as an indicator for the performance of HTA bodies. Note that the year the HTA system was established is counted as a non-HTA year.
Our first metric of analysis is the mortality rate. Figure 1 shows the average change both pre-HTA and post-HTA implementation of each. The differences in these rates are shown in the column to the far right.
The difference is calculated by subtracting pre-HTA average change by post-HTA average change. A positive difference suggests the average change in mortality rate improved after the establishment of the HTA.
The average change year over year in the mortality rate, prior to the introduction of the HTA body, was -0.35%. The average change post HTA was -0.31%. The average difference within the selected countries was -0.04%.
Notable within the data set are wide-variations between countries with prominent HTA organizations. Figure 2 shows Germany which was experiencing declines in mortality rates at an average rate of -.86% but saw them increase at an average rate of .71% in the post-HTA period.
Sweden, as shown in Figure 3, saw a reversal in trend as pre-HTA mortality rates were increasing .14% on average and, after the implementation of HTA, they saw a decrease in mortality at an average rate of -0.61%.
On the whole, the data are telling us that mortality rates did not improve after the introduction of HTA systems. While it would be inaccurate to fault HTA’s directly for the slower pace of improved mortality rates, it is clear that they had little influence in either its improvement or regression.
In our next post, we will explore life expectancy and infant mortality rates, then our conclusions from the study.