the denominations listed below did not emerge from the protestant reformation of the 16th century or its commonly acknowledged offshoots. instead, they are broadly linked to pentecostalism or similar other independent evangelical and revivalistic movements that originated in the beginning of the 20th century. for this reason, several sources tend to differentiate them from protestants and classify them as together as independents, non-core protestants etc. also included in this category are the numerous, yet very similar nondenominational churches. nonetheless, sources eventually combine their numbers to the protestant tally. despite the absence of centralized control or leadership, if considered as a single cohort, this will easily be the second largest christian tradition after roman catholicism. according to the center for the study of global christianity (csgc), there are an estimated 450 million independents world-wide, as of mid-2019.