E.b.e. - out of phase - Transformer Basics - Working principle,Construction,Types.

Abdominal pain is a high volume complaint in the ED, and there are approximately 250,000 cases of appendicitis each year.  This is a high-risk complaint: 10% of total malpractice suits against EPs involve a missed diagnosis of abdominal pain [1]. Appendicitis carries a lifetime risk of 7-8% for all patients, with 70% of cases occurring in patients less than 30 years of age and more commonly in males [2]. Appendicitis has a complex range of symptoms and atypical presentations, which can lead to missed diagnosis and potential malpractice claims. Alternatively, other etiologies may mimic appendicitis’ presentation and lead to unnecessary appendectomies, more commonly in females due to gender-specific pelvic etiologies [1].

I have small doubt about transformer
how we can find that transformer is STEPUP or stepdown.? please answer my question