Their support text is from 1 Corinthians 15:33, "Do not be deceived: evil communications corrupt good manners." Among other distinctions, the Gospel Halls would generally not use musical instruments in their services, whereas many Chapels use them and may have singing groups, choirs, "worship teams" of musicians, etc. The Gospel Halls tend to be more conservative in dress; women do not wear trousers in meetings and always have their heads covered, while in most Chapels women may wear whatever they wish, though modesty in dress serves as a guideline, and many may continue the tradition of wearing a head covering. Open Brethren churches are all independent, self-governing, local congregations with no central headquarters, although there are a number of seminaries, missions agencies, and publications that are widely supported by Brethren churches and which help to maintain a high degree of communication among them.