This is a scatter diagram, showing mean PEFR for the subject on the horizontal axis and the individual PEFR measurements on the vertical axis. There is a strong relationship, PEFR increasing with mean PEFR in a straight line. The line is not shown. The vertical spread of the points about this line is very similar all the way, with range about 70 litres per minute.
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This page maintained by Martin Bland.
Last updated: 21 April, 2008.