Complex sentence: Médecins Sans Frontières conducted a research survey in 2005 that found 11.6% of the interviewees who took part had been victims of sexual abuse since 1989.
Split into simpler sentences: Médecins Sans Frontières conducted a research survey in 2005. The survey states that 11.6% of the interviewees who took part in the study responded that they had been victims of sexual abuse since 1989.