The severity of the pain varies from one person to another, and from one headache to another in the same person.

CNN: Tension headache

The severity of the symptoms varies from mildly bothersome to virtually unbearable.

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The severity of what is happening to Asia's young varies from country to country and within those countries.

CNN: CHILDREN OF THE CRISIS

The company said it couldn't confirm that amount, and that a dose of the drug varies depending on such factors as a patient's weight and severity of bleeding.

WSJ: Hemophilia Drug's Off-Label Use Is Faulted

ILI-activity also varies significantly from season to season, both in its timing and severity, so we used ILInet data from 2003 to the most recent data points available at the time.

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