It was developed by Achenbach and Edelbrock (1987) to provide a standardized assessment of competence areas and problem behaviors in adolescents aged 11–18 based on self-reports. The scale consists of 17 competence items and 112 problem behavior items. These items related to competencies and problem behaviors are parallel to those in the Child Behavior Checklist for Ages 4–18 (CBCL 4–18) (ADDÖ). However, the items are written in the first person to enable adolescents to self-assess. The first section of the scale, the competence section, consists of the activity, social, and school subscales. The items related to activity cover the sports and non-sports activities that the boy enjoys and actively participates in, his success in these activities, the number of tasks he performs at home or outside the home, and his level of activity in these tasks. Rating is based on the quantity and quality of participation. Items related to social functioning cover membership in any club, team, or group; the number of close friends; relationships with parents and friends; and the level at which the child or adolescent can perform tasks independently. School-related items reflect academic achievement and participation in school activities, both qualitatively and quantitatively. The Total Competence score is derived from the sum of the Activity, Social Functioning, and School subscales. The scale also includes open-ended questions that gather information on whether the young man has any physical ailments or disabilities, his anxieties and problems in school-related and out-of-school settings, and his most admired traits. These items are not scored. The second section of the scale parallels the Child Behavior Checklist for Ages 4–18 (CBCL/4–18) and the Teacher’s Report Form (TRF), and consists of 112 problem items. Eighty-nine problem items are common to all three scales. Problem behaviors are rated on a scale of 0 (Not True), 1 (Sometimes or Somewhat True), and 2 (Very True or Often True) based on the frequency of occurrence over the past 6 months. The scale yields scores for “Introversion,” “Extroversion,” and “Total Problem.” The “Inward Orientation” group consists of “Social Withdrawal, Somatic Complaints, Anxiety/Depression”; the “Outward Orientation” group consists of “Criminal Behaviors and Aggressive Behaviors”; and “Total Problem” is the sum of the subtests “Social Problems, Thought Problems, and Attention Problems,” which do not fall into either group. The items in the Self-Assessment Scale for Adolescents Aged 11–18 (ÇDDÖ) were translated individually; the translations were compared, and similarities and differences were reviewed. Subsequently, the scale was reviewed by a Turkish linguist, and some corrections were made to the Turkish wording. The scale was administered to 15 adolescents to test its comprehensibility. Test-retest reliability was calculated by administering the scale twice to 60 adolescents with a one-week interval. Internal consistency was assessed using Cronbach’s Alpha coefficients calculated from the scores of the 2,206 adolescents comprising the sample in Erol’s (1998) study. The values were calculated as 80 for Internalization Problems, 81 for Externalization Problems, and 89 for Total Problems. To determine the scale’s internal consistency in the city, district, and village, Cronbach’s Alpha internal consistency coefficients were calculated based on the children’s scores, yielding the following results for the Total Problems subscale: 89 in the city center, 88 in the district, and 89 in the village. All these results indicate that the scale has high internal consistency and test-retest reliability, and that it can be reliably used with the gender and age groups examined, as well as in the province, district, and village. (Achenbach, 1991; Erol, 1997; cited in Çekici, 2003).