Table 1. Definitions of evaluation measures.

Term	Definition
Testing Time-points
At birth test	Sample collected at 0–4 weeks of age
On-time birth test	Sample collected 0–2 weeks of age
6-week test	Sample collected at 4–12 weeks of age
On-time 6w test	Sample collected at 4–8 weeks of age
Retention Definitions
Repeat POC testing	Receipt of both at birth and 6-week POC
Loss to follow up	Receipt of at birth POC, but not 6-week POC
Standard POCa	Receipt of 6-week POC, but not at birth POC
No POC	Enrolled <12 weeks of age but did not receive an at birth or 6-week POC
Delayed EID	Did not enroll until >12 weeks
Incomplete POC	Combined: Lost to follow up, Standard POC, No POC, delayed EID
Missed opportunity	Infant presented for care at given time-point but no POC test was conducted (e.g. due to machine or provider errors, cartridge stock outs, etc)

^aEquivalent to testing time points for routine EID services at the time of implementation, as national piloting of at birth testing occurred.