Measures of quality medical care for children with sickle cell disease. (A) The age when prophylactic penicillin was first prescribed for subjects with sickle cell anemia and sickle β0-thalassemia. (B) The age at first visit to our center by year of birth for all cohort subjects. (C) The age at first dose of 7-valent protein-conjugated pneumococcal vaccine (PCV-7) for all cohort subjects. The time to first PCV-7 in patients born before 2000 reflects only the age of patients at the time the vaccine became available (dotted line), not quality of care. (D) The age at first dose of 23-valent polysaccharide pneumococcal vaccine (PPV-23) for all cohort subjects. For all panels, boxes show the median and the 25th and 75th percentiles, and whiskers show the 5th and 95th percentiles. Note the logarithmic scale (base 2) of the y-axes in all panels.
