A 56-year-old woman presents to her primary care physician with complaints of painless hematuria, which she first noticed two months ago. She describes the hematuria as intermittent but more pronounced over the past week. She denies dysuria, urinary frequency, or urgency. There is no associated flank pain, fever, or weight loss. Her past medical history includes hypertension, managed with amlodipine, and she has no family history of malignancy. However, she reports a significant smoking history of 30 pack-years, having smoked one pack of cigarettes daily since her early twenties. A cystoscopy reveals a 3 cm papillary tumor on the posterior wall of the bladder, and transurethral resection of the bladder tumor (TURBT) confirms the diagnosis of urothelial carcinoma. The physician hypothesized that her smoking history of 30 pack-years contributed to her bladder cancer. His hypothesis later found to be consistent. Which of the following is an example of the Bradford Hill criterion of “consistency”?
