In this task, you are given a question and answer options for that question. Using this information, you have to classify each text into different topics: medicine, nursery, psychology, chemistry, pharmacology, biology.
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Question: Question: Regarding gastroesophageal reflux disease, which of the following statements is true?
Options: <0> The intensity and frequency of heartburn has little relationship with the presence and severity of endoscopic esophagitis. <1> Most patients with gastroesophageal reflux disease have esophagitis at endoscopy. <2> Treatment with proton pump inhibitors usually achieves good control of symptoms but is not superior to placebo in the endoscopic cure of esophagitis. <3> Barrett's esophagus can progress to low-grade epithelial dysplasia, high-grade epithelial dysplasia, and finally squamous cell carcinoma of the esophagus. <4> Endoscopic screening and surveillance programs have unequivocally shown to be able to reduce mortality in patients with Barrett's esophagus.

Answer: medicine

Question: Question: The negative feedback regulation of thyroid hormone is as follows:
Options: <0> High concentrations of circulating free T3 and T4 that elevate HRT. <1> High concentrations of circulating free T3 and T4 that raise TSH. <2> High concentrations of circulating free T3 and T4 that decrease TRH. <3> Decreased TRH that elevates TSH. <4> Decreased TSH that elevates HRT.

Answer: nursery

Question: Question: A study has been carried out to determine the risk of upper gastrointestinal bleeding (UGIB) associated with the use of different non-steroidal anti-inflammatory drugs (NSAIDs). For this purpose, 2,777 patients with UGIB and 5,532 patients matched with the previous ones were included by age and month of admission or consultation, in the same hospitals, but for reasons that had nothing to do with the use of NSAIDs. The comparative risk of suffering a UGIB associated with previous exposure to different NSAIDs was calculated. What kind of study is it?
Options: <0> Cohort study. <1> Cases and controls study. <2> Transversal study. <3> Experimental study <4> Ecological study

Answer:
medicine