This is a scatter diagram showing the difference between the two measurements of PEFR using the mini meter, on the vertical axis and the average of the two measurements of PEFR using the mini meter on the horizontal axis. There is no obvious relationship between the variables. All differences lie between -40 and + 40 except one, which is close to -100 and in the middle of the horizontal scale. One horizontal straight line is shown through zero. The points lie on either side of this.

Back to Statistical methods for assessing agreement between two methods of clinical measurement.

This page maintained by Martin Bland.

Last updated: 13 January, 2004.