Table 2.

Psychomotor development and cognitive performance of study patients with symptomatic isovaleric acidemia.

ID	Age at evaluation (y)	Psychomotor developmentb	IQ score	IQ testing toold
1	2.2	Normal	NA	DDST
2	3.8	Mild retardation	NA	DDST
3	5.3	Normal	108	K-ABC
4	6.1	Normal	106	K-ABC
5	6.5	Normal	116	K-ABC
6	7.1	Normal	108	Kramer
7	7.5	Normal	99	K-ABC
8	8.4	Learning disability	90	K-ABC
9	10.7	Learning disability	99	K-ABC
10	10.9	Mild retardation	67	K-ABC
11a	11.5	Normal	NA	NA
12	11.6	Normal	118	K-ABC
13	14.2	Learning disability	85	HAWIK-III
14	15.4	Normal	116	HAWIE-R
15a	16.5	Learning disability	93/94c, tested at age 8.5 y	CPM/CMMS
16	19	Normal	119	HAWIE-R
17a	20	Normal	101/91c, tested at age 11.6 y	SON/SPM
18a	20	Normal, speech retardation at age 3.7 y	NA	NA
19	24.4	Normal	122	HAWIE-R
20	25.3	Severe retardation	51/45c, tested at age 6.8 y	HAWIK/Kramer

Information is provided for a total number of 20 patients (one death at 13 days of life).

ID = identification number, IQ = intelligence quotient, NA = not available, y = years

^a Patient not participating in study step II.

^b According to medical records/questionnaire and, in case of participation in study step II, clinical investigation.

^c IQ testing not performed at study step II; information on IQ available from medical records/questionnaire only.

^d CMMS = Columbia Mental Maturity Scale (Mean ± SD: 100 ± 16), CPM = Raven's Coloured Progressive Matrices (Mean ± SD: 100 ± 15), DDST = Denver Developmental Screening test, HAWIE-R = Wechsler Adult Intelligence Scale-Revised (Mean ± SD: 100 ± 15), HAWIK = Wechsler Intelligence Scale for Children (Mean ± SD: 100 ± 15), HAWIK-III = Wechsler Intelligence Scale for Children Version III (Mean ± SD: 100 ± 15), K-ABC = Kaufman Assessment Battery for Children (Mean ± SD: 100 ± 15), Kramer = Kramer IQ test (Mean ± SD: 100 ± 15), NA = not available, SPM = Raven's Standard Progressive Matrices (Mean ± SD: 100 ± 15), SON = Snijders-Oomen Nichtverbaler Intelligenztest-R 5¹/₂-17 (Mean ± SD: 114 ± 14).