Operational research (OR) is a relatively new, applied branch of mathematics, which helps provide a scientific base for the management and problem‑ solving. At present, its application in public health issues is gaining importance both nationally and internationally, particularly in program management and policy making. It is an interdisciplinary team approach that requires managers and researchers to work together toward identification of the problems and implementation of optimal solutions. There is rising importance accorded by international and national agencies to invest resources in OR and guide program implementation in public health, and the global fund to fight TB, AIDS, and malaria allows up to 10% of each grant to be allocated for OR. There are multitude of research methods used in the field of health. These fields of OR, implementation research, and health system research are a source of confusion for researchers. OR may sometimes be used interchangeably with implementation research or under the subheading of health system research. OR using various qualitative and mathematical models provides solutions which are currently being applied to overcome the obstacles in health policy making and implementation. Integration of OR with monitoring and evaluation is a new paradigm in program management. This paper aims to summarize the theme, relevance, approach, methods, and applications and challenges of OR in the field of public health and how it had led to policy changes in the field of health.

Violence is a great challenge threatening the world peace. It includes a wide range of behaviors like; fight, war and genocide. There are different definitions of violence. Therefore, providing a suitable definition is necessary. In literature, according to the cultural and social text, there are different definitions for violence. The definitions are pro-vided based on the goal of research and text. The best definition is provided by WHO: "It covers a wide range of acts, going beyond physical acts to include threats and intimidation. It also includes the myriad and often less obvious consequences of violent behavior, such as physical harm, deprivation and mal development that compromise the well-being of individuals, families and communities."