Objective: To determine a local HbA,, reference range. Design: Healthy volunteers recruited into an observational study. Subjects: 262 healthy volunteers. Subjects were excluded if known to be diabetic or on medication known to interfere with glucose levels or if random capillary blood glucose was > 10 mmoVL. Results: Reference range was mean 5.5% (+/-0.5). There were differences in ethnicity, sexand age. Ethnicity: Mean HbA,, in whites (n= 135) was 5.3% (+/-0.4), which was lower than for Indo-Asians (n= 127), which was 5.7% (+/-0.5): p=O. 00 1. Sex: In females (n=140) mean HbA,, was 5.4% (+/-0.45), which was lower than for males (n= 122) 5.6% (+/-0.5): p=O. 006. Age: For white males aged 20-44 the mean value was 5.1 % compared to a mean value of 5.6% in men >65 years. White females changed from 5.0% at a g e s 2 W 4 to 5.4% for>65years. Indo-Asian females changed from 5.3% at ages 20-44 to 5.7% in women >65 years. However, for lndo-Asian men aged 20-44 the mean value was 5.6% and remained at 5.6% above the age of 65years. Conclusion: Our local reference range for DCA 2000 measurement of HbA,, has now been established and is 5.5% (+/-0.5). Two standard deviations allow the normal range to rise to 6.5%. Significant (if small) differences were seen between sex, age and ethnicity. Districts, particularly those with non-white populations, should establish local reference ranges for measurement of glycated haemoglobin. This study shows that it is practical to do so. Practical Diabetes Int 1 999; 16(6): 21 1-21 4 Key words reference range, HbA , , , ethnicity 42 37 43 122 Total 95 87 82 262 I Male
