Here is one method:
#Demonstrate the output,
c(paste0("efficacy",1:9),paste0("satisfaction",1:14),paste0("success",1:7))
[1] "efficacy1" "efficacy2" "efficacy3" "efficacy4" "efficacy5"
[6] "efficacy6" "efficacy7" "efficacy8" "efficacy9" "satisfaction1"
[11] "satisfaction2" "satisfaction3" "satisfaction4" "satisfaction5" "satisfaction6"
[16] "satisfaction7" "satisfaction8" "satisfaction9" "satisfaction10" "satisfaction11"
[21] "satisfaction12" "satisfaction13" "satisfaction14" "success1" "success2"
[26] "success3" "success4" "success5" "success6" "success7"
#Assign the names
colnames(DF) <- c(paste0("efficacy",1:9),paste0("satisfaction",1:14),paste0("success",1:7))