Article Text

Download PDFPDF
Discriminant Function Analysis as an Aid to the Diagnosis of Flax Byssinosis
  1. J. D. Merrett
  1. Department of Medical Statistics, The Queen's University of Belfast


    A simple discriminant function in four variates (area of mill, average number of cigarettes currently smoked per day, a complex of dyspnoea, cough, and wheezing grades, and occupation) was derived to discriminate between non-byssinotic (grade o) and byssinotic (grades I and II) preparers. This function diagnosed 14% of non-byssinotics as byssinotic and 35% of byssinotics as non-byssinotic, giving a total misclassification rate (24·5%) that agreed closely with the theoretically expected rate (26·4%). Similar misclassification rates were found in a randomly selected check sample of preparers. The function did not diagnose accurately preparers with early byssinosis (grade ½); 64% of such workers would have been diagnosed as normal.

    Statistics from

    Request Permissions

    If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.