Whether ceftazidime monotherapy is equal in efficacy to combination regimens (Comb) for empiric treatment of febrile neutropenic patients was tested using meta-analysis. Published studies and abstracts of ceftazidime trials were identified, their quality assessed, the efficacy data abstracted and pooled, and effects of patient and study characteristics examined. The pooled odds ratio (OR) of failure of ceftazidime for febrile episodes was 1.27 (95% confidence interval [CI]: 0.79-2.03; n = 1077) and for bacteremic episodes was 0.72 (CI, 0.33-1.58; n = 248; OR less than 1.0 favors ceftazidime). Results were not significantly affected by type of antibiotic in Comb, age, neutropenia (less than 500/mm3), study quality, or combining abstracts. Results indicate that Comb does not offer a significant advantage over ceftazidime. A subgroup of profoundly neutropenic (less than 100/mm3) patients could not be assessed, raising the possibility that in this important subgroup monotherapy and Comb may not be equivalent. Use of ceftazidime empirically may require modification based on microbiologic results and clinical course.