The main difficulties encountered in the integration of ethics in Health Technology Assessment (HTA) were identified in our systematic review. In the process of analyzing these difficulties we then addressed the question of the diversity of ethical approaches (1) and the difficulties in their operationalization (2,3).

Nine ethical approaches were identified: principlism, casuistry, coherence analysis, wide reflexive equilibrium, axiology, socratic approach, triangular method, constructive technology assessment and social shaping of technology. Three criteria were used to clarify the nature of each of these approaches:

1. 1. The characteristics of the ethical evaluation

2. 2. The disciplinary foundation of the ethical evaluation

3. 3. The operational process of the ethical evaluation in HTA analysis.

In HTA, both norm-based ethics and value-based ethics are mobilized. This duality is fundamental since it proposes two different ethical evaluations: the first is based on the conformity to a norm, whereas the second rests on the actualization of values. The disciplinary foundation generates diversity as philosophy, sociology and theology propose different justifications for ethical evaluation. At the operational level, ethical evaluation's characteristics are applied to the case at stake by specific practical reasoning. In a norm-based practical reasoning, one must substantiate the facts that will be correlated to a moral norm for clearly identifying conformity or non-conformity. In value-based practical reasoning, one must identify the impacts of the object of assessment that will be subject to ethical evaluation. Two difficulties arise: how to apply values to facts and prioritize amongst conflicting ethical evaluations of the impacts?

Applying these three criteria to ethical approaches in HTA helps understanding their complexity and the difficulty of operationalizing them in HTA tools. The choice of any ethical evaluations is never neutral; it must be justified by a moral point of view. Developing tools for ethics in HTA is operationalizing a specific practical reasoning in ethics.