Likewise, the relative LOS of ICU admissions in July ± September was nearly identical to admissions in October ± June in major teaching hospitals (1.00; 95% CI, 0.98 ± 1.02). This was also true in minor teaching and non-teaching hospitals. CONCLUSION: We found no evidence to support the existence of a July phenomenon in ICU patients. Patients admitted to teaching hospital ICUs during July, August, and September, have similar adjusted mortality and LOS. These findings suggest that residency programs may compensate for the inexperience of new housestaff during the first 3 months of the academic year.