Cuba's government permitted the formation of the Yoruba Cultural Association, a non-governmental organization, in the early 1990s. In July 2003, Havana hosted the Eighth World Orisha Conference. Various practitioners of Santería made visits to Nigeria to study traditional Yoruban religion there. The late twentieth century saw a growth in the "yorubización" ('Yorubization') of Santería, with attempts made to remove Roman Catholic elements from the religion and make it more closely resemble West African religion. This process was promoted at the International Workshop of Yoruba Culture, which was held in Cuba in 1992. Within Cuba, the Yorubization process was often attributed as reflecting the influence of practitioners in the United States. Cuban cultural nationalists were critical of the Yorubization process, viewing Santería's syncretism as a positive trait and arguing that advocates of Yorubization presented homogenous societies as superior to heterogenous ones. Many Santeros who opposed the reforms highlighted that even in West Africa, orisha-worship never foregrounded ideas of purity and exclusivity. The head of the Roman Catholic Church in Cuba, Cardinal Jaime Lucas Ortega y Alamino, also opposed the Yorubization process, believing that the Roman Catholic elements of Santería were a positive influence within the religion. The close of the twentieth century also saw adherents of Santería increasingly utilise the internet to promote the religion. Ascertaining the number of Santería practitioners is complicated by the fact that many individuals do not take part in its rituals but turn to its practitioners for assistance on matters of health and other practical issues. Based on his ethnographic work in New York City during the 1980s, Gregory noted that he did not believe Santería could be seen as a "religion of the poor", observing a disproportionately high percentage of middle-class people such as teachers, social workers, and artists in the movement. Some practitioners grow up in the religion, as the child of initiates, although others only approach the religion as an adult. Within Cuba, Santería is practiced in both rural and urban areas and has both Afro-Cuban and Euro-Cuban practitioners. On the island, Santería is practiced primarily in the north-west provinces of Havana and Matanzas. There are divergent opinions regarding how many people practice Afro-Cuban religions on the island. In 1991, the Cuban anthropologist López Valdés suggested that about 90 percent of Cuba's population practiced some form of religion and that of that 90 percent, a greater number practiced one of the Afro-Cuban religions than "pure Catholicism".