Objective: The objective of this study was to assess the role played by the patient's age and physician's experience in determining the contamination rate of pediatric blood cultures.
Methods: The proportion of true-positive (isolation of a pathogen) and false-positive (isolation of a contaminant) results among blood cultures obtained by in-training physicians and experienced pediatricians from young children (aged 1-35 months) and older children (>or=36 months of age) and the value of a positive blood culture to predict a true-positive result were retrospectively determined.
Results: The odds of a positive blood culture to predict isolation of a true-pathogen was 0.366 only when the sample was obtained by an inexperienced physician and 0.523 when it was drawn by an experienced physician (P < 0.001), 0.419 when it was obtained from a young child and 0.429 when it was drawn from an older child (P = 0.781). The predictive value of a positive result for isolating a pathogen was significant higher when an experienced physician drew the blood culture regardless of the patient's age.
Conclusions: Patient's young age and lack of experience of the physician who draws the specimen increase the risk of blood culture contamination. These results strengthen the need to improve the technical skills of young physicians.