PGF and preeclampsia: For instance, while PlGF was the most reliable predictor of late-onset preeclampsia in the interval 22.1–28 weeks, being included in the best combination 24/100 times, when all data was used to fit the final model, RAN and METAP1 appeared to be the best choices even though they were selected 12 and 16 times in the best combination out of 100 bootstrap trials.