External validation of models to predict the outcome of pregnancies of unknown location: a multicentre cohort study.
Evangelia ChristodoulouS BobdiwalaC KyriacouJ FarrenN Mitchell-JonesF AyimB ChohanO AbughazzaB GuruwadahyarhalliM Al-MemarS GuhaV VathananD GouldC StalderLaure WynantsDirk TimmermanTom BourneBen Van CalsterPublished in: BJOG : an international journal of obstetrics and gynaecology (2020)
The M6 model, as part of a two-step triage strategy, is the best approach to characterise and triage PULs.