Bland and Altman (1986) provide data on the peak expiratory flow rates (PEFR) for 17 subjects measured using two different meters – LWPFM and SWPFM – which are provided in PEFR.MTW and reproduced by permission of The Lancet. Display the data as for the example given earlier and confirm that the limits of agreement are -78 to 74. The authors state that the standard error of the limits is given approximately by √3s2/n, where the standard deviation of the differences and n is the number of parts measured. Calculate approximate 95% confidence intervals for the limits of agreement.