Decision rule sets are used widely to classify the conservation status of s
pecies. These classifications are intended to approximate the relative degr
ee of threat faced by different species. They are important because they pl
ay a role in setting conservation priorities. It is suggested that such rul
e sets should take into account estimates of the statistical distribution a
nd confidence intervals reported for each of the parameters. Examples are p
rovided for three threatened Australian plant species. (C) 1999 Published b
y Elsevier Science Ltd. All rights reserved.