Unknown enameled insignia

[Milmed]

Hi,
Acquired these as part of a job lot, but not sure what they represent.

All are gilt with enameling in blue and white. Attachments are a mix of pin and clasp, buttonhole and sliders.

Made by Toye & Co Ltd. London.

The 'COMMITTEE' one has letters 'A.E. & O.T.I' above but a google search did not help identify anything.

Thanks for any assistance

Steven