Objective: In 1994, the American Academy of Pediatrics (AAP) published a practice guideline with age-specific thresholds for phototherapy for healthy term newborns with hyperbilirubinemia. The purpose of this study was to examine adherence to the guideline in a large managed care organization.
Methods: We conducted a retrospective cross-sectional analysis of linked computerized databases from 11 Northern California Kaiser Permanente Medical Care Program hospitals. Newborn infants included were at least 37 weeks of gestation, had birth weights of at least 2500 g, and were born between January 1, 1995, and December 31, 1996. The primary outcome variable for the study was receipt of phototherapy according to the guideline. Total serum bilirubin (TSB) and infant age in hours at the time of bilirubin measurement were used to classify infants into 3 groups according to the AAP guideline: recommend phototherapy (R), consider phototherapy (C), and did not recommend phototherapy (N). Group R included infants with TSB levels of at least 15 mg/dL before 48 hours of age, at least 18 mg/dL before 72 hours, or at least 20 mg/dL after 72 hours. Group C included infants not in group R, with TSB levels of at least 12 mg/dL before 48 hours, 15 mg/dL before 72 hours, or at least 17 mg/dL after 72 hours. Group N included infants who were in neither group R nor group C and also did not have significant jaundice before 24 hours of age. Phototherapy codes from electronic databases were validated by chart review for a subset of 550 infants.
Results: Compared with chart review, phototherapy codes in the database were 94.4% sensitive (95% confidence interval [CI]: 89.1%-97.5%) and 100% specific (95% CI: 99.25%-100%). Among the 47 801 infants eligible, 2.3% received phototherapy. Phototherapy was administered to 54% of 1194 infants in group R (range across hospitals: 27%-77%), 16% of 2245 infants in group C (range: 5%-37%), and 0.2% of 44 362 infants in group N (range: 0.1%-0.6%). The predictors of phototherapy for group R, the group for whom phototherapy was recommended, determined by logistic regression were increasing TSB levels (odds ratio [OR]: 1.6/mg/dL; 95% CI: 1.4-1.7), reaching the AAP threshold at 24 to 47.9 hours of age compared with 48 hours or more (OR: 7.1; 95% CI: 4.3-11.9), gestational age of 37 weeks compared with 38 weeks or more (OR: 1.6; 95% CI: 1.1-2.3), age when phototherapy was first recommended (OR: 0.7/d; 95% CI: 0.6-0.8), and facility of birth (OR: 0.2-2.7). The facility of birth was a strong predictor of phototherapy use in all groups (R, C, and N).
Conclusions: Clinicians provided phototherapy to only 54% of term infants with hyperbilirubinemia for whom it was recommended by the AAP. There is marked interhospital variation in phototherapy use in this large managed care system. Improved adherence to the guideline would require only a slight increase in the total rate of phototherapy use if unnecessary use for infants with lower levels of TSB were simultaneously decreased.