Standardization in laboratory medicine: Adoption of common reference intervals to the Croatian population

Table 3 Verification of reference intervals for aspartate amino-transferase for Croatian patients

Analyte	Method	Unit	Reference interval			Ref.	Verification (%)
			Sex	Age (yr)	Interval
AST	Photometry UV, IFCC method, 37 °C, TRIS buffer, L-aspartate, α-ketoglutarate, pyridoxal phosphate, NADH, malate dehydrogenase, lactate dehydrogenase, pH 7.65: CCMB recommendation for the Croatian population	U/L	Male, female	0-2	26-75	[40]
			Male, female	3-7	24-49	[40]
			Male, female	8-12	14-39	[10,15]
			Male	13-19	11-38	[10,15]
			Female	13-19	14-32	[10,15]
			Male	≥ 20	11-38	[14]
			Female	≥ 20	8-30	[14]
	IFCC reference measurement procedure (IFCC RMS), IFCC IRMM reference material ERM-AD457 (2002): Common multicentric reference intervals for the adult population, 2010	U/L	Male, female	18-85	11-34	[41]	94
	Pediatric reference intervals
	CALIPER, Canada, 2012; IFCC reference measurement procedure, Abbott Architect		Male, female	1 < 7	26-55	[42]	100
			Male, female	7 < 12	22-41		96
			Male	12 < 19	18-40		96
			Female	12 < 19	17-33		96
	Denmark (NORIP), 2012; IFCC reference measurement procedure, Roche Modular		Male, female	5-18	17-46	[43]
	Germany (a posteriori, ambulance and hospital populations) 2009; IFCC reference measurement procedure, Roche Modular		Male, female	0-1	< 77	[44]
			Male, female	1-3	< 71
			Male, female	4-6	< 53
			Male, female	7-12	< 48
			Male	13-17	< 42
			Female	13-17	< 44

AST: Aspartate amino-transferase; IFCC: International Federation of Clinical Chemistry and Laboratory Medicine; CCMB: Croatian Chamber of Medical Biochemists; IRMM: Institute for reference materials and measurements; RMS: Reference measurement system; CALIPER: Canadian laboratory initiative on pediatric reference intervals.