Package in Depends field not imported from: 'survival'
  These packages need to be imported from (in the NAMESPACE file)
  for when this namespace is loaded but not attached.
crossmatchtest: no visible global function definition for 'pnorm'
Undefined global functions or variables:
  pnorm
Consider adding
  importFrom("stats", "pnorm")
to your NAMESPACE file.
Package in Depends field not imported from: ‘survival’
  These packages need to be imported from (in the NAMESPACE file)
  for when this namespace is loaded but not attached.
crossmatchtest: no visible global function definition for ‘pnorm’
Undefined global functions or variables:
  pnorm
Consider adding
  importFrom("stats", "pnorm")
to your NAMESPACE file.