A framework for measuring the cost to families of caring for children’s health: the design, methodology, and study population of the r-Kids study oleh Joanna E. Bulkley, Alexandra M. Varga, John F. Dickerson, Phil Crawford, Lisa A. Croen, Yihe G. Daida, Eric Fombonne, Brigit Hatch, April Lee, Maria Massolo, Katherine Vaughn, Frances L. Lynch