Indirect determination of pediatric blood count reference intervals

Area of Science:

• Clinical Laboratory Science
• Pediatric Laboratory Medicine
• Biostatistics

Background:

• Establishing pediatric reference intervals (RIs) for laboratory tests is challenging due to age-related variations and difficulties in sampling healthy children.
• Current RIs often rely on small sample sizes and arbitrary age groupings.
• Intra-laboratory RIs tailored to specific populations and analytical devices are not widely adopted.

Purpose of the Study:

• To develop continuous, age-dependent pediatric reference intervals (RIs) for blood count and sodium levels.
• To utilize a large clinical laboratory database for deriving these RIs.
• To address limitations of traditional RI determination methods.

Main Methods:

• A refined indirect approach was employed using a dataset of 60,000 individual samples.
• Samples were stratified by age, and a density function estimated the proportion of healthy samples.
• Continuous RIs were generated by merging age-specific results.

Main Results:

• Continuous, age-dependent RIs were successfully generated for pediatric blood counts and sodium.
• The derived RIs demonstrated high concordance with established laboratory instruments and conventional methods.
• Age-dependent dynamics of reference limits were accurately captured.

Conclusions:

• The indirect method is effective for creating continuous, intra-laboratory RIs from clinical databases.
• Generated RIs are comparable to those from established methods, offering a viable alternative.
• This approach is transferable to other laboratory quantities, especially where conventional methods are limited.