So accurate we call it the Error - Proof Test. Analog - Traditional fibrous. Pregnant. Not pregnant. Clear results over 99% Accurate (Over 99% accurate from the day of expected period at detecting typical pregnancy hormone levels. Note that hormone levels vary. See leaflet). No brand more accurate. Testing Before Missed Period? For best results it is recommended you test the day of your expected period. Levels of the pregnancy hormone vary greatly, which makes testing earlier less reliable. If you test early and get a negative result, the distributor of e.p.t recommends retesting on the day of your expected period.