Short answers, pulled from the story.
Lightner Witmer opened the first psychological clinic at the University of Pennsylvania in 1896. This event marked the beginning of clinical psychology as a distinct field.
Three main educational models developed in the US include the PhD Clinical Science model focused on research and the PhD science-practitioner model integrating scientific research and practice. The Doctor of Psychology degree emerged from the Vail Conference on Professional Training in Psychology resulting in 1973.
Clinical psychologists require a license to practice in countries like the United States, Canada, the United Kingdom, India, and Pakistan. Each country maintains specific regulatory bodies such as the Health Professions Council in the UK or the Rehabilitation Council of India.
Only seven US states allow clinical psychologists with advanced specialty training to prescribe psychotropic medications. These states include Louisiana New Mexico Illinois Iowa Idaho Colorado and Utah.
A debate first described in detail in 1954 by Paul Meehl explored whether mechanical methods could outperform clinical judgment. Subsequent meta-analyses have borne out Meehl's conclusion that mechanical modes perform as well or better than clinical modes.