The auxiliary hospital at Medari was founded in 1914 and was situated along the large road from Yogyakarta to Magelang. The initiator was the missionary Pruys, who founded the hospital with the help of the Colonial Bank.It was sponsored by the sugar mill at Medari and was the second auxiliary hospital that was founded by the Zending van de Gereformeerde Kerken in Nederland. The hospital was an affiliation of the large Petronella hospital at Yogyakarta. In the jubilee edition (1896-1936) of the Petronella hospital the pages 10 and 46 this hospital is mentioned: the auxiliary hospital receives a subsidy from the government. Its outpatient clinic is well visited. The hospital has on average 50 inpatients. It has a few VIP rooms for well to do Javanese, but it is open for the entire population, as are all auxiliary hospitals that are run by the mission. It is mainly financed by the sugar factory, but this does not mean that patients who are not employed by the factory may not be admitted. There is (1936) one head nurse and a second mantri-nurse. The building is in a good condition and the maintenance is carried out on a regular base by the sugar factory.
The hospital started in 1914 as a small category 1 hospital (10-25 beds) and received initially f 5,560 for the building and f 2,250 for the initial equipment. At that time the subsidy for personnel was only f 120 and for other expenditure f 1001 (Koloniaal Verslag 1915, Annex T-XI. In later issues of the Koloniaal Verslag the administrator of the Medari sugar factory is mentioned as beneficiary. The hospital has in the meantime beene enlarged to a category II hospital (26-75 beds). In 1929 the subsidy from the government was f 1,440 for personnel and f 2,410 for other expenditure (Koloniaal Verslag 1930, Annex O-XI).