The basal body temperature rise actually occurs after ovulation, too late to take full advantage of your fertile time in that cycle. The advantage of the Clearblue Advanced Digital Ovulation Test, which tracks hormones, over the basal body temperature method is that it identifies the days before ovulation happens; this gives you more time to take advantage of more of your fertile days.
The Clearblue Advanced Digital Ovulation Test shows your 2 Peak Fertility days, which is the same as other ovulation tests. But unlike other ovulation tests it also detects a rise in estrogen which precedes the LH surge, typically identifying an extra 2 or more days of High Fertility. This way you will know all the days when intercourse is most likely to lead to conception.