The topics considered in the study included beliefs about the Bible, importance of a relationship with God, and the existence of Satan. In regard to personal behavior, areas considered included church-going habits, prayer, and making a personal commitment to Christ.
A particularly interesting finding from the research was that, in comparison to 15 years ago, African Americans have grown even stronger in their faith in a number of areas:
"Six of seven measures of belief had changed significantly. Blacks today are more likely than they were in the early 1990s to believe that the principles taught in the Bible are totally accurate; to say that their religious faith is very important in their life; to have a biblically orthodox understanding of the nature of God; and to be born again.As with any study such as this, these are general findings and do not hold true for everyone that is an African American. But the importance that many in the black community place on the Christian faith indicates the resilience of the black church in the midst of sweeping cultural change within the American mainstream.
Three of the five behavioral measures that were evaluated both recently and 15 years ago showed substantial change. Those efforts included an increase in the proportion of African-Americans who have made a personally important commitment to Christ, church attendance, and Bible reading.
You can read more about the Barna study here.