Compared to 25 control churches , 26 churches receiving the social marketing program had a higher median proportion ( 9.8 % vs. 0.3 % ; p < 0.001 ) and mean number ( 7.0 vs. 0.5 ; IRR = 11.2 [ 95 % CI : 7.5 , 16.8 ] ) of older adult congregants who joined balance classes .