title: A study of persistent absentees and their families.
mesh_terms: D000041:Absenteeism; D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D006801:Humans; D007859:Learning Disabilities / Q000523:psychology; D010287:Parent-Child Relations; D012959:Socioeconomic Factors; D014505:Urban Population