Jacobus de Rooij studied medicine in Amsterdam, where he sat for his medical finals on 28 June 1907. He worked for the Rijksverzekeringsbank in Amsterdam. De Rooij lived at 37 Ruyschdaelkade in Amsterdam. He obtained his PhD on 7 May 1940 in Amsterdam on the basis of a doctoral thesis on 'Operations on ulcers and the duodenum in connection with the invalidity law'.
J.H. Coppenhagen, Anafiem Gedoe‘iem. Overleden joodse artsen uit Nederland 1940-1945 (Rotterdam 2000) 132-133
In addition, a Jokos file (number 52977) on this family is at the Amsterdam Municipal Archive. Access is subject to authorization from the Stichting Joods Maatschappelijk Werk.