Stratified sampling is often used when one or more of the stratums in the population have a low incidence relative to the other stratums. Convenience sampling is used in exploratory research where the researcher is interested in getting an inexpensive approximation of the truth.
Millions of Americans live with various types of mental illness and mental health problems, such as social anxiety, obsessive compulsive disorder, drug addiction, and personality disorders. Treatment options include medication and psychotherapy.
Mental illness refers to a wide range of mental health conditions â disorders that affect your mood, thinking and behavior. Examples of mental illness include depression, anxiety disorders, schizophrenia, eating disorders and addictive behaviors. Many people have mental health concerns from time to time.