He also obtained a master"s degree in Economics and a Doctor of Philosophy in applied mathematics in Economics at the Claude-Bernard University (France), and an Accreditation to Supervise Research (Habilitation a Diriger des Recherches).
Beresniak is a physician specialized in Public Health from the Faculty of Medicine at University of Marseille, France. Beresniak was Head of Health Economics for Glaxo-Wellcome (1993-1999) and Global Head of Pharmacoeconomics for Serono International (1999-2004). Since 2005, Beresniak is Chief Executive Officer of Data Mining International.
He has been short-term consultant for the World Health Organization and the European commission in the fields of Public health and Health Economics.
Beresniak is author of the reference book "Health Economics" published in French and Portuguese. He publishes two dictionaries: one dictionary of Health Economics published in French and Spanish, and one dictionary of terms used in health industries published in French.
Beresniak is also coauthor of "Understanding Pharmacoeconomics" published in French and "Pharmacoeconomics" published in Japanese. Beresniak is known to have led the ECHOUTCOME project, a European Commission funded research, establishing that the QALY indicator (Quality Adjusted Life Years) is not scientifically validated to be used in Decision making and could lead to divergent results with the same dataset.
These findings have generated an international controversy because the QALY indicator is still currently promoted as reference case by some national health technology assessment agencies such as the NICE (National Institute for Health and care Excellence) in the United Kingdom. Beresniak is also project leader of the FLURESP project, a European Commission funded research, with the objective to compare cost-effectiveness of various public health interventions against human pandemic influenza.
Member of French Society Health Economics (vice president since 2002), Latin American Association Advancement of Health Systems (board director since 1998).