Stratification in clinical trials of febrile neutropenia.

Patients with febrile neutropenia are characterized by well described prognostic factors leading to heterogeneity of risk of serious clinical outcomes. These prognostic factors complicate the design and interpretation of clinical trials of antimicrobial therapy in this population. Stratification is a method by which comparability of groups is ensured. This method can be employed prior to randomization or during the analysis. Factors that should be considered for stratification prior to randomization include the underlying neoplasm (leukemia vs solid tumor vs BMT), use of granulocyte growth factors, comorbid conditions and study site (in multicenter trials). In stratified analyses, trend in neutrophil count, site of infection, organism and susceptibility should be considered.