That being said, the Catholic Church was not frequently able or even willing to enforce such overly strict interpretations of the prohibition. It usually only enforced consanguinity laws when it wanted to apply political pressure on a secular lord seeking a marriage, and conversely, would often grant dispensation to a lord seeking to marry his third cousin if he was on good terms with the Church (. gave them generous land donations). By the thirteenth century, however, it was decided to finally update the official Church laws on incest to reflect the fact that they were using the new Germanic method of reckoning blood relatives: thus the Fourth Lateran Council of 1215 officially lowered the number of degrees in which marriage is forbidden from seven to four. This does not mean that long-held prohibitions on incest were suddenly relaxed, but rather that the laws and method of reckoning were finally brought closer back to their original alignment, forbidding marriage between what we would call "second cousins". Actually, the new rules in 1215 were slightly more strict in that two persons are related within four Germanic degrees of kinship if they share the same great-great-grandparents, which means that third cousins or closer were forbidden to marry (which was still far less than forbidding marriage between sixth cousins).
A recent paper analyzed data from the PLCO using a complicated statistical model to account for the fact that some men in the PLCO trial who were assigned to the control group had nevertheless undergone PSA screening. This analysis suggested that the level of benefit in the PLCO and ERSPC trials were similar and that both trials were consistent with some reduction in prostate cancer death in association with prostate cancer screening ( 6 ). Such statistical modeling studies have important limitations and rely on unverified assumptions that can render their findings questionable (or more suitable for further study than to serve as a basis for screening guidelines). More importantly, the model could not provide an assessment of the balance of benefits versus harms from screening.