Laboratory Medicine and Quality Assurance

Table. 3. Table 3

Cut-off values used in expanded neonatal screening tests using tandem mass spectrometry in the first trial in 2016

Variable	Unit	Mean	Median	Minimum	Maximum	No. of institutions
Amino acids
Alanine	umol/L	683.79	681.8	340.97	1,100.5	15
Arginine	umol/L	57.84	59.5	30.5	78.46	15
Aspartate	umol/L	175.77	166.38	150	239.3	6
Citrulline	umol/L	50.29	46	35.9	67.9	15
Glutamate	umol/L	574.7	563	300	850	7
Glycine	umol/L	987.72	1,000	420	1,497	15
Histidine	umol/L	208.81	143.52	2.38	925	14
Leucine+isoleucine	umol/L	291.42	300	222	351.4	15
Methionine	umol/L	59.07	60	46	81.2	15
Ornithine	umol/L	310.86	300	180	488	15
Phenylalanine	umol/L	117.4	115.77	100.3	139.3	16
Proline	umol/L	432.69	382.29	7.52	1523	14
Tyrosine	umol/L	299.83	298.7	249	402	15
Valine	umol/L	262.35	260	210.59	300.8	15
Methionine/phenylalanine		1.06	1	0.51	2	14
Phenylalanine/tyrosine		2.41	2	1.24	4.8	15
Acylcarnitines
C0	umol/L	65.56	62.2	45.02	100	15
C2	umol/L	53.81	50	37.6	90	15
C3	umol/L	5.54	5.4	3.59	7	15
C4	umol/L	0.82	0.8	0.46	1.4	15
C5	umol/L	0.72	0.7	0.4	1	15
C6	umol/L	0.27	0.23	0.1	0.52	15
C8	umol/L	0.37	0.39	0.15	0.51	15
C10	umol/L	0.36	0.32	0.21	0.56	15
C12	umol/L	0.45	0.43	0.24	0.8	15
C14	umol/L	0.66	0.67	0.38	0.9	15
C16	umol/L	6.57	6.69	5.08	8.5	15
C18	umol/L	2	2	0.8	2.88	15
C5DC	umol/L	0.25	0.26	0.14	0.35	15
C5OH	umol/L	0.58	0.59	0.36	0.81	14
C3/C2		0.25	0.27	0.1	0.38	15
C5/C3		0.92	0.52	0.2	2.5	14
C8/C10		3.58	3.32	0.83	8.57	9
C5/C0		0.24	0.03	0.01	1.52	9
C5/C2		0.08	0.05	0.01	0.21	14
C8/C2		0.04	0.03	0.01	0.1	15