The top three criteria for determining psychological disorders are deviance, maladaptive behavior, and personal distress. How one defines normal depends on the society one lives in. Although every Culture has ideals of what they consider normal behavior, these ideals vary from one Culture to another. When someone deviates from their respective cultures ideal of normal, They may be labeled mentally ill. The book gives the example of fetishism, where A man is sexually aroused by dressing in women clothing. While this is seen as abnormal in Our society, in some cultures it's normal.
When someones everyday adaptive behavior is impaired they are often said to have psychological disorder. The book gives the example of substance use disorders. This is the Key factor in the diagnosis of substance use disorders. When a persons drug and / or alcohol Use begins to interfere with their job performance or social functioning, a substance use disorder exists.
Often times, people do not exhibit any abnormal or maladaptive behaviors, but instead report feelings of personal distress. An example being depression or anxiety disorders. These people are labeled as having a disorder when they describe their subjective pain and Suffering to friends, relatives, and or doctors. The challenge of using these criteria in a way that is consistent with the theme That psychology is empirical involves valve judgement's. Because the diagnoses of psychological disorders involves judgement's of what is normal or abnormal, these diagnoses tend to vary from culture to culture.
Where-as in our culture cross-dressing is looked upon as Abnormal, other cultures consider it normal, it depends on the cultures in which the behavior is found.