Thoroughly updated and revised to emphasize the link between research and evidence-based practice, this ninth edition of a classic textbook presents state-of-the-art methods for conducting high-quality studies. Key features: new! The updated section pertaining to the & lsquomixed method of research – combining qualitative and quantitative research is all new! Research Tips: Throughout the book, point out quick and key information to students' new chapters: two chapters on mixed methods research which involves the blending of qualitative and quantitative data into a single inquiry. (Chapters 25, 26) New: New guidelines for obtaining research funding from the National Institutes of Health. New: a revised model for developing and testing interventions (the 2008 Medical Research Council framework) new: approaches to systematic reviews