def default_user
      scg = specimen_collection_group || (specimen.specimen_collection_group if specimen) || return
      cp = scg.collection_protocol || return
      cp.coordinators.first || (cp.sites.first.coordinator if cp.sites.size === 1)
    end
def default_user
      scg = specimen_collection_group || (specimen.specimen_collection_group if specimen) || return
      cp = scg.collection_protocol || return
      cp.coordinators.first || (cp.sites.first.coordinator if cp.sites.size === 1)
    end
Returns the first SCG CP coordinator, if any.