Other California KIPP schools showed the same pattern in my research, confirmed and amplified by a study of the Bay Area KIPP schools by the research organization SRI International.

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He said a similar pattern would be expected in other countries which were not analysed in the study.

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The study, by Hasselt University in Belgium, comes after Scottish research in 2012 found a similar pattern.

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Osterholm's study suggests this has been a general pattern in American public health history with relation to the flu vaccine.

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Researchers recruited 48 adults for the study who were asked to learn and perform a specific finger pattern (pushing keys on a keyboard in a particular sequence as fast as possible in 30 seconds).

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