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- update to Subject Screening form validation (488-10, 638)
- allow screening age < 18 (though requires consent, and will be ineligible) (638)
- allow Serum CrAg date on/before CD4 date (488-10)
- allow Serum CrAg date > 21 days apart from CD4 date (488-10)
- tighten validation of dates against report_datetime
- update Chest X-ray form validation to now allow x-ray date up to 7
days before consent date (786-2)