Few instruments have been developed to screen emotional and behavioural problems and mental disorders using questionnaire methods in a broad study, as will be done in the Health Survey for Children and Adolescents. In the context of this survey's pretest, two questionnaires--the Child Behavior Checklist (CBCL) and the Strengths and Difficulties Questionnaire (SDQ)--were compared regarding their psychometric properties, their diagnostic power, and the study participants' acceptance of the instruments. With this comparison, the question was addressed concerning which of the two questionnaires mentioned above is more reliable, valid and acceptable to the participants in describing mental health problems and psychiatric disorders in a population-based survey intended for a target age group of 6 to 17-year olds. The results of this methodical comparison show that both instruments are comparably useful for screening purposes. Both instruments detected mental disorders that were established in a clinical interview with equal probability. In this regard, the self-report tends to be superior to the parents' report in the age group from 11 to 17 years. The SDQ displays a slightly higher acceptance and--in comparison to the CBCL--a considerably lower number of items. It can therefore be recommended for use in the survey.
