3Wahlgren D R,Meltzer S B,Jones J A,et al.Quality of life in low income latino children with asthma.Ann Behav Med,1999,21:S93.
4Gostmaker SL,Walker DK. Weitzman M,et al. Chronic conditions socioeconomic risks and behavioral problems in children and adolescents. Pediatrics,1990,85:267.