Since the late twentieth century, clinical psychology is considered the most popular branch of psychology. The term was first introduced in 1907 in a paper by US psychologist Lightner Witmer (1867 to 1956), a former student of Wilhelm Maximilian Wundt (1832 to 1920). According to Witmer clinical psychology is "the study of individuals, by observation or experimentation, with the intention of promoting change." Still there is no officially accepted definition of the term.
Clinical psychology developed from the concept in modern psychology that there are huge differences between people. Philosophers have been discussing the issue for many years arguing whether these individual differences are inborn or a result of experience. However, that topic attracted real interest in psychologists as late as the beginning of the nineteenth century.
In general clinical psychology tries to assess and treat various mental illnesses, psychiatric problems and abnormal behaviour. It applies psychological principles to the assessment, prevention and rehabilitation of psychological distress, disabilities, dysfunctional behaviour and others. Clinical psychology features both scientific research focused on general principles and clinical service with emphasis on the study and care of patients. Information gathered from these activities influences practice and research. Clinical psychology has a broad approach to individual and interpersonal human problems. It caters for children, adolescents, adults, couples, whole families, various groups, organizations and systems.
Clinical psychology often overlaps with other professional fields of psychology such as counselling psychology and clinical neuropsychology. It can also mix with psychiatry, social work and other professional fields outside psychology. Apart from psychology, the historical development of clinical psychology has been impacted by many other sciences, factors and forces. These include philosophy, biological sciences, political movements and more.
The work of a clinical psychologist depends on the situations, his or her position and the orientation of the organization in which he or she works. If employed at a hospital, a clinical psychologist may have to deal with tasks such as diagnostic intelligence testing, case evaluation and therapeutic recommendation, as well as therapeutic contacts and supervision of training and research. Being a clinical psychiatrist means that one can be a psychometrist, a psychiatrist or just a scientist. Other responsibilities may include offering testimony in legal settings, teaching, drug and alcohol treatment and research.
Assessment, diagnosis, intervention, research and consultation or program development are among the key skill areas for one's work as a clinical psychologist.
Assessment may include interviewing, systematic observation and psychometric testing of the patient and the people that are close to him or her. Clinical psychologists apply a lot of assessment methods so they should be adequately trained to find the most appropriate one.
Clinical psychologists have to make functional diagnoses regarding intellectual level, cognitive, emotional, social, behavioural functioning, mental and psychological disorders. Diagnoses can be made formally or informally.
Next comes the phase of intervention or treatment. It is of high importance for a clinical psychologist to be able to develop and maintain functional therapeutic relationships with patients that can often be highly distressed and sensitive. Intervention seeks to help individuals to make adequate choices and gain control of their own lives.
Since World War II (1939 to 1945) clinical psychologists have taken more responsibility for the diagnosis and treatment of various clinical patients. Clinical psychologists are needed in various facilities such as prisons, detention homes, schools, rehabilitation agencies, military facilities, research agencies, community service agencies and more. Bearing in mind the huge variety of organizations, it is hard to give a clear definition of what a clinical psychologist is trained and allowed to do.
There are several treatment approaches in clinical psychology when one is dealing with patients. The psychodynamic approach is among the major theoretical perspectives within clinical psychology. It is a result of the work of Sigmund Freud (1856 to 1939). According to him the unconscious mind has significant impact on one's behaviour. Psychologists using the psychodynamic approach rely on free association and other techniques to find out their patient's unconscious motivations.
The cognitive behavioural approach, on the other hand, comes from the behavioural and cognitive schools of thought. It focuses on the interaction between one's feelings, thoughts and actions. Cognitive-behavioural therapy aims to alter the patient's thoughts and reactions that result in psychological distress.
Another major theoretical perspective is the humanistic one. It developed through the work of humanist thinkers such as Abraham Maslow (1908-1970) and Carl Rogers (1902-1987). Psychologists utilizing that approach look at their patients more holistically. They try to help people realize their full potential.