The integration of information from numerous sources where a psychologist satisfies this information from tests such as personality, intelligence, attitudes, and information obtained from personal interviews. Collateral information on personal, professional and medical history is also collected. This data is collected from interviews and reports from parents, friends, spouses, teachers, employers, previous therapists, and doctors. Psychological tests are only one of the data sources used in the evaluation process, it is possible to provide much more than one test and in most cases they allow to obtain information for the psychological evaluation. This process is very valuable when providing a diagnosis for treatment. In order for useful psychological measures to be collected, the measures must be valid and reliable. This is not magic; the psychologist relies on the information collected to provide a consistent diagnosis of pathology and relapse