The Strengths and Difficulties Questionnaire is a short screening questionnaire for children aged three to 16 years that gives reliable information on emotional health, conduct problems, hyperactivity, peer relationship problems and pro social behavior. Also known after its originator as Goodman's SDQ, the instrument exists in several versions to meet the needs of researchers and clinicians, and has been published in over 50 languages. An impact supplement asks parents, teachers or the child about chronicity, distress, social impairment, and burden to others if a mental health problem exists. Some applications also ask two follow-up questions "Has the intervention reduced problems?" and "Has the intervention helped in other ways, for example by making the problems more bearable?"