This is a scatter diagram, showing mean PEFR for the subject on the horizontal axis and the standard deviation of PEFR for the subject on the vertical axis. There is no obvious relationship. There are two points which may be outliers, at roughly mean = 260 standard deviation = 40 and mean = 300 standard deviation = 55. No other standard deviation is greater than 30.

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This page maintained by Martin Bland.

Last updated: 21 April, 2008.