input: The following are multiple choice questions (with answers) about medical knowledge.   The "July effect" refers to the phenomenon of adverse impacts on patient care arising from the changeover in medical staff that takes place during this month at academic medical centres in North America. There has been some evidence supporting the presence of the July effect, including data from surgical specialties. Uniformity of care, regardless of time of year, is required for patients undergoing major cancer surgery. We therefore sought to perform a population-level assessment for the presence of a July effect in this field. We used the Nationwide Inpatient Sample to abstract data on patients undergoing 1 of 8 major cancer surgeries at academic medical centres between Jan. 1, 1999, and Dec. 30, 2009. The primary outcomes examined were postoperative complications and in-hospital mortality. Univariate analyses and subsequently multivariate analyses, controlling for patient and hospital characteristics, were performed to identify whether the time of surgery was an independent predictor of outcome after major cancer surgery. On univariate analysis, the overall postoperative complication rate, as well as genitourinary and hematologic complications specifically, was higher in July than the rest of the year. However, on multivariate analysis, only hematologic complications were significantly higher in July, with no difference in overall postoperative complication rate or in-hospital mortality for all 8 surgeries considered separately or together.   **Question:** Is there any evidence of a "July effect" in patients undergoing major cancer surgery?   (A) Yes   (B) No   (C) Maybe
output: ['(B) No <> answer', 'The following are multiple choice questions (with answers) about medical knowledge. <> instruction', '(A) Yes  (B) No  (C) Maybe <> possible answers', 'The "July effect" refers to the phenomenon of adverse impacts on patient care arising from the changeover in medical staff that takes place during this month at academic medical centres in North America. There has been some evidence supporting the presence of the July effect, including data from surgical specialties. Uniformity of care, regardless of time of year, is required for patients undergoing major cancer surgery. We therefore sought to perform a population-level assessment for the presence of a July effect in this field. We used the Nationwide Inpatient Sample to abstract data on patients undergoing 1 of 8 major cancer surgeries at academic medical centres between Jan. 1, 1999, and Dec. 30, 2009. The primary outcomes examined were postoperative complications and in-hospital mortality. Univariate analyses and subsequently multivariate analyses, controlling for patient and hospital characteristics, were performed to identify whether the time of surgery was an independent predictor of outcome after major cancer surgery. On univariate analysis, the overall postoperative complication rate, as well as genitourinary and hematologic complications specifically, was higher in July than the rest of the year. However, on multivariate analysis, only hematologic complications were significantly higher in July, with no difference in overall postoperative complication rate or in-hospital mortality for all 8 surgeries considered separately or together. \n   Is there any evidence of a "July effect" in patients undergoing major cancer surgery? <> context']