The scheme was also referred to as the "Group System" as men were classified in groups according to their year of birth and marital status and were to be called up with their group when it was required. The scheme proved unsuccessful and was abandoned in December 1915, in spite of the fact that the execution of Nurse Edith Cavell by the Germans, on 12 October 1915 was used in recruitment rallies by Lord Derby. It was superseded by the Military Service Act 1916 which introduced conscription.