British Colonialism dominated Malaya (Tanah Melayu) in 1856. The most striking outfit as we look back at British Colonialism is British clothes. For the early Malay doctors, some wore pith helmets.
The pith helmet (also known as the safari helmet, sun helmet, topee, sola topee, salacot or topi) is a lightweight cloth-covered helmet made of cork or pith (typically pith from the sola, Aeschynomene aspera, an Indian swamp plant, or A. paludosa, or a similar plant). Designed to shade the wearer's head and face from the sun, pith helmets were once often worn by Westerners in the tropics, but have also been used in other contexts. Source: Wikipedia.
In three B/W photos taken during the flood that hit Kelantan circa 1914/15, the British doctors wore pith helmets as they went about their daily work either in sampan or horse carriage (courtesy of Muzium Kelantan; photos are not shown here).
In a B/W portrait of Dr Husin bin Mohamed circa 1916, he wore a pith helmet (courtesy of his children; photo is not shown here).
There maybe other photos of the early Malay doctors sporting pith helmets as part of their formal doctor's white uniform.