A comparison of methods for analysing red cell and platelet volume-distribution curves

Cell volume-distribution curves may be analysed using log-probability paper or by considering volumes corresponding to frequencies of 50 or 60% of that at the mode. All methods give similar results; the log-probability paper method is better because it allows the researcher to check that the underlying distribution is lognormal; methods based on 50 or 60% modal frequency are slightly less reliable but are simpler for routine use. For platelets it may be convenient to estimate the curve from the modal volume and the volume above the mode at which the frequency is reduced to 60% of the modal frequency.