Fig. 4From: Previously unidentified duplicate registrations of clinical trials: an exploratory analysis of registry data worldwideKnown duplicates among highly similar records. Highly similar pairs (light gray) and the fraction that are known duplicates (dark gray). Pairs with similarity between 0.5 and 0.6 were identified but are not shown due to their large number (64 % of all pairs with a score over 0.5)Back to article page