This article documents the expansion of college education in the United States and examines to what extent the increase in the number of college graduates may have lead to a decline in the average quality of college graduates. Using the 1940-90 Census, we compare across birth year cohorts with varying levels of college completion. We find some weak evidence that college graduate men from highly educated cohorts earn a relatively smaller wage premium even controlling for the relative supply effect. However, these cohort quality effects account for only a small fraction of the recent fluctuation in the college wage premium. (JEL I20, J24, J31) *We thank two anonymous referees for comments and suggestions on earlier drafts. Juhn: Professor,

PurposeThis study aimed to determine the optimal initial vancomycin dose to achieve appropriate trough levels in pediatric patients.MethodsWe analyzed clinical data for 309 children treated with intravenous vancomycin between 2004 and 2009 at 2 different hospitals in South Korea. The patients were 1-16 years old and exhibited normal renal function. Patient data, including reason for treatment and initial dosing regimen, were reviewed. Two subgroups were identified and compared according to initial vancomycin dose: 40 (35-45) mg/kg/day and 60 (55-65) mg/kg/day. Trough levels were obtained at steady state after at least 4 doses of vancomycin.ResultsPatients who received vancomycin had post-operation or wound-related infections (37.2%), localized infection (12.9%), catheter-related infections (9.4%), meningitis (8.7%), or endocarditis (6.8%). Pathogens were confirmed in 79 cases: 28 cases of methicillin-resistant Staphylococcus epidermidis (35.4%) and 25 of methicillin-resistant Staphylococcus aureus (31.6%). Out of the 309 patients, 201 (65%) received vancomycin at 40 mg/kg/day and 108 (35%) at 60 mg/kg/day. Average trough concentrations were significantly different between the groups (P<0.001). Trough levels over 10 mg/L were less likely to be achieved in the 40 mg/kg/day group (14%) than in the 60 mg/kg/day group (49%) (P<0.001). There were no differences in renal function deterioration between the groups.ConclusionA common vancomycin dosing regimen, 40 mg/kg/day, was not high enough to achieve trough levels of over 10 mg/L in pediatric patients. Careful drug monitoring must be performed, and increasing initial dose of vancomycin should be considered in pediatric patients.

Mycoplasma pneumoniae is a common cause of respiratory tract infections. M. pneumoniae infection frequently manifests with extrapulmonary symptoms such as central nervous system complications, skin or mucosal involvement, and gastrointestinal problems. However, cardiac complications associated with M. pneumoniae are rarely reported. We report the case of a 47-month-old girl who died of fulminant myocarditis associated with M. pneumoniae pneumonia. (Korean J Pediatr Infect Dis 2009;16:92-96)

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