Adolescent Behavior: Any observable response or action of an adolescent.Family Therapy: A form of group psychotherapy. It involves treatment of more than one member of the family simultaneously in the same session.Parent-Child Relations: The interactions between parent and child.Substance-Related Disorders: Disorders related to substance abuse.Adolescent Psychology: Field of psychology concerned with the normal and abnormal behavior of adolescents. It includes mental processes as well as observable responses.Behavior, Animal: The observable response an animal makes to any situation.Feeding Behavior: Behavioral responses or sequences associated with eating including modes of feeding, rhythmic patterns of eating, and time intervals.Adolescent Development: The continuous sequential physiological and psychological changes during ADOLESCENCE, approximately between the age of 13 and 18.Adolescent Health Services: Organized services to provide health care to adolescents, ages ranging from 13 through 18 years.Health Behavior: Behaviors expressed by individuals to protect, maintain or promote their health status. For example, proper diet, and appropriate exercise are activities perceived to influence health status. Life style is closely associated with health behavior and factors influencing life style are socioeconomic, educational, and cultural.Social Behavior: Any behavior caused by or affecting another individual, usually of the same species.Sexual Behavior: Sexual activities of humans.Adolescent Medicine: A branch of medicine pertaining to the diagnosis and treatment of diseases occurring during the period of ADOLESCENCE.Behavior: The observable response of a man or animal to a situation.Questionnaires: Predetermined sets of questions used to collect data - clinical data, social status, occupational group, etc. The term is often applied to a self-completed survey instrument.Peer Group: Group composed of associates of same species, approximately the same age, and usually of similar rank or social status.Child Behavior: Any observable response or action of a child from 24 months through 12 years of age. For neonates or children younger than 24 months, INFANT BEHAVIOR is available.Risk-Taking: Undertaking a task involving a challenge for achievement or a desirable goal in which there is a lack of certainty or a fear of failure. It may also include the exhibiting of certain behaviors whose outcomes may present a risk to the individual or to those associated with him or her.Adolescent Psychiatry: The medical science that deals with the origin, diagnosis, prevention, and treatment of mental disorders in individuals 13-18 years.Adolescent Nutritional Physiological Phenomena: Nutritional physiology of children aged 13-18 years.Sexual Behavior, Animal: Sexual activities of animals.Exploratory Behavior: The tendency to explore or investigate a novel environment. It is considered a motivation not clearly distinguishable from curiosity.Child Behavior Disorders: Disturbances considered to be pathological based on age and stage appropriateness, e.g., conduct disturbances and anaclitic depression. This concept does not include psychoneuroses, psychoses, or personality disorders with fixed patterns.Cross-Sectional Studies: Studies in which the presence or absence of disease or other health-related variables are determined in each member of the study population or in a representative sample at one particular time. This contrasts with LONGITUDINAL STUDIES which are followed over a period of time.Longitudinal Studies: Studies in which variables relating to an individual or group of individuals are assessed over a period of time.Behavior Therapy: The application of modern theories of learning and conditioning in the treatment of behavior disorders.Parents: Persons functioning as natural, adoptive, or substitute parents. The heading includes the concept of parenthood as well as preparation for becoming a parent.Aggression: Behavior which may be manifested by destructive and attacking action which is verbal or physical, by covert attitudes of hostility or by obstructionism.Maternal Behavior: The behavior patterns associated with or characteristic of a mother.Parenting: Performing the role of a parent by care-giving, nurturance, and protection of the child by a natural or substitute parent. The parent supports the child by exercising authority and through consistent, empathic, appropriate behavior in response to the child's needs. PARENTING differs from CHILD REARING in that in child rearing the emphasis is on the act of training or bringing up the children and the interaction between the parent and child, while parenting emphasizes the responsibility and qualities of exemplary behavior of the parent.Age Factors: Age as a constituent element or influence contributing to the production of a result. It may be applicable to the cause or the effect of a circumstance. It is used with human or animal concepts but should be differentiated from AGING, a physiological process, and TIME FACTORS which refers only to the passage of time.Motor Activity: The physical activity of a human or an animal as a behavioral phenomenon.Sex Factors: Maleness or femaleness as a constituent element or influence contributing to the production of a result. It may be applicable to the cause or effect of a circumstance. It is used with human or animal concepts but should be differentiated from SEX CHARACTERISTICS, anatomical or physiological manifestations of sex, and from SEX DISTRIBUTION, the number of males and females in given circumstances.Pregnancy in Adolescence: Pregnancy in human adolescent females under the age of 19.Schools: Educational institutions.Social Environment: The aggregate of social and cultural institutions, forms, patterns, and processes that influence the life of an individual or community.Interpersonal Relations: The reciprocal interaction of two or more persons.Risk Factors: An aspect of personal behavior or lifestyle, environmental exposure, or inborn or inherited characteristic, which, on the basis of epidemiologic evidence, is known to be associated with a health-related condition considered important to prevent.United StatesFriends: Persons whom one knows, likes, and trusts.Prevalence: The total number of cases of a given disease in a specified population at a designated time. It is differentiated from INCIDENCE, which refers to the number of new cases in the population at a given time.Alcohol Drinking: Behaviors associated with the ingesting of alcoholic beverages, including social drinking.Stereotyped Behavior: Relatively invariant mode of behavior elicited or determined by a particular situation; may be verbal, postural, or expressive.Self-Injurious Behavior: Behavior in which persons hurt or harm themselves without the motive of suicide or of sexual deviation.Students: Individuals enrolled in a school or formal educational program.