Hematological health-related intervals estimated using an indirect method in order to satisfy the accreditation standards

The estimation of reference limits represents quite a taxing task for labor atories which frequently adopt the limits suggested by manufacturers or tho se reported in the literature. This practice does not meet the requirements of accreditation programs (i.e. Essential Criteria, Clinical Pathology Acc reditation) that require laboratories to produce or check all their referen ce intervals. We collected 15 244 hematological results from females aged 0 -99 years obtained by the Rovereto Hospital Laboratory and calculated the r eference intervals, or to be more precise the health-related intervals, usi ng an indirect method (based on all the inpatient and outpatient results). All the measurements were carried out using an automatic Coulter STK S anal yzer, and the results were transferred to Verona by e-mail. The results for hemoglobin were: <1 year (n = 154) = 90-171 g/l; 2-8 years (n = 619) = 104 -136 g/l; 9-14 years (n = 322) = 118-143 g/l; 15-44 years (n = 6329) = 106- 144 g/l; 45-75 years (n = 4893) = 107-148 g/l; 75-99 years (n = 2927) = 90- 153 g/l. The results appear different from the results currently used by Ro vereto Hospital (120-160 g/l) but comparable to those reported in the liter ature with the exception of the subjects under 1 year and over 75 years, pr obably due to the excess of "diseased" subjects in these classes. The indir ect method allows even small laboratories to produce or check their referen ce intervals for all age groups, increasing the clinical effectiveness of l aboratory results and satisfying the accreditation standards.