Given a passage with a context and an answer, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.

Example Input: Context: Small studies suggest exogenous estrogen may improve vitamin D status, but the etiology is unclear because women who use hormones may make lifestyle choices that differentially affect vitamin D status.', 'Our objective was to investigate the association between use of hormonal contraception and 25-hydroxy-vitamin D (25(OH)D).', 'We used linear regression modeling of cross-sectional data to estimate percent change in season-adjusted serum 25(OH)D with estrogen use after adjustment for other factors.', 'At the enrollment clinic visit (2010-2012) into a cohort study of uterine fibroids, each subject provided a blood sample, had anthropomorphic variables and skin reflectance measured, and answered questionnaires on demographics, dietary and supplement intake, contraceptive use, reproductive and medical history, and behaviors.', 'A total of 1662 African American women, community volunteers, 23-34 years old, living in the Detroit, Michigan, area were included.', 'None.', 'Serum 25(OH)D was measured.', 'Serum 25(OH)D concentrations were low (70% <20 ng/ml). Current use of an estrogen-containing contraceptive was associated with a 20% (95% confidence interval: 14-27) increase in 25(OH)D after adjustment. There was no increase in 25(OH)D among participants who had used estrogen in the past, but were not current users, indicating that results were unlikely to be due to unmeasured confounding by factors related to contraceptive choice.
Answer: The increase in 25(OH)D with use of estrogen-containing contraceptives raise mechanistic questions regarding the biological pathways involved, and highlights the need for studies that examine possible endogenous estrogen effects on vitamin D.
Example Output: Does use of Estrogen-Containing Contraception be Associated With Increased Concentrations of 25-Hydroxy Vitamin D?

Example Input: Context: To assess the effects of treatment with antitumour necrosis factor (TNF) agents, methotrexate, or other non-biological disease-modifying antirheumatic drugs (DMARDs) on cardiovascular event risks among patients with rheumatoid arthritis (RA).', "We conducted a retrospective study using data from the MarketScan claims database. Patients with RA with ≥1 prescription for an index drug were included. Each patient's use of an index drug was calculated cumulatively as a time-varying exposure. The incidence of cardiovascular events among patients with RA was determined. Associations between drug exposures and occurrence of cardiovascular events were assessed with Cox proportional hazards models.", 'Of 113\u2005677 patients identified, 35.8%, 41.1% and 23.1% received anti-TNF agents, methotrexate and other DMARDs, respectively. Patients were treated for an average of 7.6\u2005months; 2138 patients (1.9%) had a cardiovascular event following their index prescription. Each additional 6\u2005months of anti-TNF therapy use versus non-use reduced the risk (HR; 95% CI) for any cardiovascular event by 12% (0.88; 0.81 to 0.95, p=0.002). Anti-TNF therapy was associated with a 13% and 12% reduction in cardiovascular events in patients aged ≥50\u2005years (0.87; 0.80 to 0.95, p=0.002) and in those without prior methotrexate use (0.88; 0.78 to 0.99, p=0.04), respectively. Cumulative use of 1, 2 or 3\u2005years of anti-TNF therapy versus non-use is expected to reduce cardiovascular event risks by 21%, 38% and 51%, respectively.
Answer: Anti-TNF therapy was associated with a significantly lower risk of cardiovascular events among patients with RA, older patients with RA and patients without prior exposure to methotrexate.
Example Output: Are longer durations of antitumour necrosis factor treatment associated with reduced risk of cardiovascular events in patients with rheumatoid arthritis?

Example Input: Context: Adenosine diphosphate (ADP) is involved in shear-induced platelet activation, which may be important for platelet responses to stress. We therefore tested the hypothesis that ADP receptor antagonism by clopidogrel treatment would attenuate exercise-induced platelet activation.', 'Fifteen healthy volunteers performed exhaustive exercise without and with clopidogrel pretreatment (75 mg/day; 7 days) in a randomised crossover study. Filtragometry readings (reflecting platelet aggregability in vivo) and 11-dehydro-thromboxane B(2) (TxM) in plasma were determined before and after exercise. Platelet and leukocyte activity, platelet-platelet (PPA), and platelet-leukocyte aggregates (PLAs) in vivo and their responsiveness to agonist stimulation in vitro were assessed by flow cytometry. Clopidogrel treatment inhibited ADP-induced platelet P-selectin expression by 72% (54-85%). Exercise increased platelet aggregation (filtragometry and PPAs), elevated plasma TxM, increased single platelet P-selectin expression, elevated circulating PLAs, and enhanced ADP and thrombin-stimulated P-selectin expression. Clopidogrel prolonged filtragometry readings and attenuated agonist stimulated P-selectin expression at rest, but did not influence TxM in plasma or urine or attenuate platelet or leukocyte responses to exercise. Clopidogrel treatment did not influence plasma CD40L (ligand) at rest or after exercise.
Answer: Clopidogrel treatment attenuates platelet activity in vivo at rest, but exercise counteracts the platelet stabilizing effects of clopidogrel. The hypothesis that ADP is involved in stress-induced platelet activation was not supported.
Example Output:
Are prothrombotic responses to exercise little influenced by clopidogrel treatment?