A survey of hemoglobin values in Canada.

A compilation of hemoglobin values has been made from submissions from laboratories in Canada using the cyanmethemoglobin standard prepared and distributed by the Canadian Communicable Disease Centre (formerly the Laboratory of Hygiene). From 84 participating laboratories 21,580 values were analyzed statistically by age and sex. "Medical referrals", exclusive of blood dyscrasias, were included but were documented separately from "well persons". In most age groupings no significant difference in these two categories was found.Values for boys and girls were similar up to 12 years of age. For adult women from 18 to 84 years the mean value was 13.0 g. per 100 ml. (95% confidence limits 10.8-15.2 g.); for pregnant women 19 to 44 years the mean value was 12.2 g. per 100 ml. (9.7-14.6 g.). For men aged 17 to 24 years the mean value was 15.0 g. per 100 ml. (12.8-17.3 g.); 25-49 years 14.6 g. per 100 ml. (12.4-16.9 g.); 50-69 years 14.3 g. per 100 ml. (11.8-16.8 g.). It is noteworthy that for the most part the mean values were slightly lower than those frequently quoted as "normal" and that the mean values, particularly for the male, were lower with increasing age.