Data collection and statistical analyses
Two trained pediatric oncology physicians (DJB and CIW) abstracted data
from the patients’ medical records using a standardized data collection
form in REDCap, an electronic data management platform. The form was
first pilot-tested by the two clinicians and modified to ensure the data
of interest was collected. To ensure consistency, the two clinicians met
before abstracting data and throughout data collection to reach
consensus on definitions. Each clinician also independently reviewed two
records that had been abstracted by the other and no discrepancies were
found. Descriptive statistics were used to summarize patient
demographics, clinical characteristics, toxicities, and outcomes,
including frequencies and proportions for categorical variables and
medians and ranges for continuous variables. Statistical analyses were
performed using SAS version 9.4 (SAS Institute, Cary, NC).