This is a scatter diagram.
The horizontal axis shows Baseline standard deviation of peak expiratory flow in litres per minute and is numbered 0, 20, 40, 60, 80, 100. The vertical axis shows standard deviation of peak expiratory flow after six months in litres per minute and is numbered 0, 20, 40, 60, 80, 100.
There are two overlapping clouds of points labeled Intervention and Control. Both clouds are roughly triangular. The Intervention cloud has an apex at about baseline = 8, 6 months = 8, a horizontal side to baseline = 55, 6 months = 8, and a rising side to baseline = 50, 6 months = 70. The Conrol cloud has an apex at about baseline = 6, 6 months = 8, an almost horizontal side to baseline = 85, 6 months = 15, and a rising side to baseline = 55, 6 months = 90.
The control cloud tends to be higher than the intervention cloud.
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This page maintained by Martin Bland.
Last updated 7 July, 2009.