Indirect determination of pediatric blood count reference intervals

Determination of pediatric reference intervals (RIs) for laboratory quantities including hematological quantities is complex. The measured quantities vary by age, and obtaining samples from healthy children is difficult. Many available RIs are derived from small sample numbers and split into arbitrary discrete age intervals. To overcome these shortcomings, we applied a refined indirect approach to generate RIs using data derived from 60,000 patient samples of our routine laboratory. Continuous intra-laboratory RIs were determined for blood count quantities from birth to adulthood. Comparison analyses showed that the indirect RIs closely match RIs generated with considerable expense by established methods. The presented approach can easily be transferred to any laboratory quantity and might therefore be used as an alternative method for RI determination where classical approaches cannot be applied.