B. Patient populations vary substantially in average severity of illness from hospital to hospital.

不同的医院的病人群体在平均疾病严重程度上不同。

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The records showed it took an average of about 10 million years for an ecosystem to become re-established, irrespective of the severity of the extinction.

BBC: Intel follows speedy chip debut

Moreover, other data reviewed by Audit Analytics suggests that the severity of 2012 restatements, as measured by both the impact on net income and by the average number of issues per restatement, was generally less than in the period prior to 2008.

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