Gap analysis of pediatric reference intervals related to thyroid hormones and the growth hormone–insulin growth factor axis

Canadian Laboratory Initiative on Pediatric Reference Interval Database (CALIPER): Pediatric reference intervals for an integrated clinical chemistry and immunoassay analyzer, Abbott ARCHITECT ci8200

“…Consequently, clinical laboratory accreditation organizations and licensing agencies require that each laboratory verifies or establishes reference intervals for each method. A recent series of gap analyses of reference intervals available for various pediatric disease biomarkers [7][8][9][10][11] revealed major gaps in the available pediatric reference intervals, largely due to less than optimum number of subjects studied and obtained with older methodologies [12][13][14]. The current routine practice of applying reference intervals obtained on older methodologies/instruments to interpret results obtained on current methods and platforms is clearly questionable and likely contributes to erroneous interpretation and diagnosis.…”

Closing the Gaps in Pediatric Laboratory Reference Intervals: A CALIPER Database of 40 Biochemical Markers in a Healthy and Multiethnic Population of Children

“…Many of the reference intervals in current use have been derived from the analysis of a small number of healthy or hospitalized individuals or are focused on a limited age interval with restricted partitions (11)(12)(13)(14)(15). Because of the challenges with recruiting study participants, only a small number of analytes have been studied (16 -18 ).…”

Paediatric reference interval and biological variation trends of thyrotropin (TSH) and free thyroxine (T4) in an Asian population

“…If a large age interval predominantly contained older children, the reference values would be skewed lower since TSH declines with advancing age. It has been suggested that the upper reference value for TSH reaches that of the adult by 30–60 days of age, although in some children this decline may be more gradual 2. Alternately, study population, exclusion criteria, statistical method and instrument used may contribute to the difference seen.…”

“…A gap analysis performed previously recommended the recruitment of sample size representative of particular and well-defined populations 2. At the same time, it identified the difficulty in obtaining sufficient sample size as a key obstacle.…”

“…Simply, the direct sampling approach involves recruitment of a cohort of subjects who have been determined to be free of any conditions that may affect the analyte of interest 2 3. Generally, 120 subjects are required for each set of reference intervals.…”