Another White National Gallery
These pictures are from the 1982 Ladybird kids' book People Who Help Us - The Nurse. The dresses shown here look to be identical in cut to the 'National'; but are made from a plain material rather than the distinctive check used in the more common versions. This is clearer in the larger pictures I've put in the Photo Album. What's clearly shown here is the use of different coloured belts, epaulettes and cap bands to denote rank and grade.
Larger version
Larger version