The purpose of this study is to assess the agreement of clinical performance between the proposed NeoPlex 4 assay and NeoPlex System and the comparator devices in clinical use in newborn screening programs for detection of T4, TSH, 17-OHP and IRT.

The proposed (investigational) NeoPlex4 assay measures levels of thyroxine (T4), thyrotropin (hTSH), 17-alpha-OH-progesterone (17-OHP) and immunoreactive trypsinogen (IRT) from dried blood specimens (DBS) collected from neonates to screen for congenital hypothyroidism (CH), congenital adrenal hyperplasia (CAH) and cystic fibrosis (CF). The Clinical Evaluation of the xMAP® NeoPlex4™ Assay (NeoPlex4) for Detection of T4, TSH, 17-OHP and IRT using the NeoPlex System is a multi-center method concordance study on a combination of prospectively collected neonatal dried blood spots and pre-selected archived frozen dried blood spots that have been demonstrated to be positive for 17-OHP (CAH), IRT (CF), and T4 or TSH (CH). The study will be conducted at selected sites that routinely perform newborn screening testing in the United States.

Inclusion Criteria:

• The dried blood spot specimen was collected on an FDA-cleared collection paper that has not yet passed its expiration dating.
• Prospective specimens used in this study should only be those collected for the first time from a subject, or initial collection specimens.

Exclusion Criteria:

• Collected within 24 hours of birth.
• Specimens stored at ambient temperature for greater than 14 days prior to testing.
• The specimen DBS appears diluted.
• The specimen DBS shows evidence of clotting, caking, layering or serum rings.
• The DBS punched disks were punched too close to the edge of the blood spot or show printed markings.
• The specimen or collection card was contaminated with fecal material.
• Non-eluting blood spot due to deterioration of sample caused by exposure to heat and humidity.

Specimens will be derived from prospectively collected neonatal specimens and banked neonatal specimens originating from hospitals, birthing centers, and/or clinics. Newborn screening is currently performed on all neonates; there is no selection criterion for subjects.