In the 20th and 21st centuries, and in particular since the 1990s, there has been increased activity on both the national and international levels to research, raise awareness and advocate for the prevention of all kinds of violence against women. Most often, violence against women has been framed as a health issue, and also as a violation of human rights. A study in 2002 estimated that at least one in five women in the world had been physically or sexually abused by a man sometime in their lives, and "gender-based violence accounts for as much death and ill-health in women aged 15–44 years as cancer, and is a greater cause of ill-health than malaria and traffic accidents combined."