original passage: Cluster headaches are relatively uncommon. They affect only 1–3 per thousand people in the world. Cluster headaches affect approximately three times as many men as women.
original sentence: Cluster headaches are relatively uncommon.
sentence2: If an ER patient gave an account of symptoms that sounded like those of cluster headaches, would doctors first try to eliminate other diagnoses that were more likely to be the cause?
sentence1: Cluster headaches are quite rare . They affect only 1–3 per thousand people in the world. Cluster headaches affect approximately three times as many men as women.