“…Iron deficiency anaemia, as conventionally defined in clinical practice, for example the criteria in W H O (1959), has been shown to be common in this country in women of all ages (Kilpatrick, 1961), and in the elderly o f both sexes (Kilpatrick & Hardisty, 1961; Parsons, Withey & Kilpatrick, 1965). However the evidence presented in these and many other similar studies is based simply on the proportion of persons found to have levels of circulating haemoglobin below 'the lower limit of the normal range' and this point in the distribution of haelnoglobin levels is usually chosen in an arbitrary manner.…”