Table 4.

Comparison of U.S. newborn screening outcomes for X-ALD across six publications plus the present study. Positive screens and how those were classified as various diagnoses or false-positive cases were defined by their respective authors.

State	Publication	Study Length	Total # Screened	Positive Screens	Male X-ALD	Female Heterozygote	Peroxisome Biogenesis Disorder	Other Genetic Syndrome
California	Matteson et al., 2021 [43]	4 years	1,854,631	355	95	110	23	12
Georgia	Hall et al., 2020 [42]	7 months	51,081	11	1	0	2	0
Illinois	Burton et al., 2022 [44]	1 year 11 months	276,000	34 a	7	10 b	3	0
New York	Moser et al., 2016 [2]	2 years 8 months	630,000	53	20 c	22	- d	- d
North Carolina	Lee et al., 2020 [41]	6 months	52,301	12	3	3	1	1
Minnesota	Wiens et al., 2019 [40]	1 year	67,836	14	9	5	0	0
Pennsylvania	Present Study	4 years 2 months	542,554	51	21	23	4	0

^a Illinois also employs a system in which initial dried blood spot C26:0-LPC levels ≥0.28 µmol/L are considered positive and levels 0.18–0.28 µmol/L are considered borderline. Repeat dried blood spot specimens are requested for borderline cases and considered positive if C26:0-LPC levels are ≥0.28 µmol/L or borderline if C26:0-LPC levels are 0.18–0.28 µmol/L. Here, all positive screens are included, regardless of whether they were positive on the first or second dried blood spot specimen. ^b One female individual was found to be homozygous for her ABCD1 variant due to isodisomy X and is included in this number. ^c One male individual was found to be heterozygous for his ABCD1 variant due to 47,XXY and is included in this number. ^d Ten cases screened positive but did not harbor an identified ABCD1 variant. It was included whether any of these cases represented alternative diagnoses.