Given a passage, 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.

Ex Input:
Obese patients with idiopathic pulmonary fibrosis (IPF) have higher 90-day mortality after lung transplantation. We sought to determine whether body mass index (BMI) differentially modified the effect of transplant procedure type on 90-day mortality in IPF patients.', 'We analyzed data from the Organ Procurement and Transplantation Network (OPTN) for all patients with IPF who were transplanted between 2000 and 2010. Post-transplant survival was examined using Kaplan-Meier estimates. Multivariable logistic regression modeling was used to determine the difference in 90-day survival. The primary variable of interest was the interaction term between body mass index (BMI) and transplant type.', 'A total of 3,389 (58% single-lung transplant [SLT] and 42% bilateral lung transplant [BLT]) subjects were included. Multivariable logistic regression modeling demonstrated a statistically significant interaction between BMI and transplant type (p = 0.047). Patients with a BMI > 30 kg/m(2) who received a BLT are 1.71 times (95% CI [1.03 to 2.85], p = 0.038) more likely to die within 90 days than BLT recipients with a BMI of 18.5 to 30 kg/m(2).

Ex Output:
Do obese patients with idiopathic pulmonary fibrosis have a higher 90-day mortality risk with bilateral lung transplantation?


Ex Input:
We investigated whether a computed tomography (CT)-based score could predict a large infarct (≥ 80 mL) on early diffusion-weighted magnetic resonance imaging (DWI).', 'Acute stroke patients considered for endovascular therapy within 8 hours of the onset of symptoms were included. The Alberta Stroke Program Early Computed Tomography Score (ASPECTS) was determined on noncontrast CT and computed tomography angiography source images (CTA-SI). Limited collateral flow was defined as less than 50% collateral filling on CTA-SI.', 'Fifty-six patients were analyzed. National Institutes of Health Stroke Scale score was 20 (15-24) in the large infarct group and 16 (11-20) in the small infarct group (P = .049). ASPECTS on noncontrast CT and CTA-SI was 5 (3-8) and 3 (2-6) in the large infarct group and 9 (8-10) and 8 (7-9) in the small infarct group (both P < .001), respectively. Limited collateral flow was frequent in the large infarct group than in the small infarct group (92% vs. 11%, P < .001). Multivariate analysis found that CTA-SI ASPECTS less than or equal to 5 (odds ratio [OR], 40.55; 95% confidence interval [CI], 1.10-1493.44; P = .044) and limited collateral flow (OR, 114.64; 95% CI, 1.93-6812.79; P = .023) were associated with a large infarct. Absence of ASPECTS less than or equal to 5 and limited collateral flow on CTA-SI predicted absence of a large infarct with a sensitivity of .89, specificity of 1.00, positive predictive value of 1.00, and negative predictive value of .71.

Ex Output:
Do collateral flow and brain changes on computed tomography angiography predict infarct volume on early diffusion-weighted imaging?


Ex Input:
Pathophysiological mechanisms associated with neoplastic progression in patients with short-segment Barrett's oesophagus (SSBO), who represent the vast majority of the Barrett population, have not been defined.", 'To evaluate pathophysiological characteristics of patients with SSBO and dysplasia detected at 3-year surveillance endoscopy (incident dysplasia).', 'Patients with SSBO underwent impedance-pH monitoring during heartburn-suppressing PPI therapy. Fifteen patients (12 males, median age 62 years) with incident dysplasia and 50 patients (43 males, median age 59 years) without dysplasia were compared. Impedance-pH parameters, including chemical clearance assessed by the post-reflux swallow-induced peristaltic wave (PSPW) index, were evaluated.', 'All patients declared persisting heartburn suppression on maintenance PPI therapy at 3-year follow-up, 58/65 (89%) with standard dosages. The median gastric and oesophageal acid exposure time (GAET and OAET) did not differ between patients with and without incident dysplasia at the time of surveillance (36% and 0.6% vs. 33% and 0.5%) or index endoscopy (33% and 0.3% vs. 41% and 0.5%) (P > 0.05). Contrastingly, the median PSPW index was significantly lower in patients with than in patients without incident dysplasia at the time of surveillance (15%, vs. 32%) and index endoscopy (12% vs. 30%) (P = 0.001). The PSPW index, the GAET and the OAET did not vary over time (P > 0.05). A PSPW index <26% was predictive of incident dysplasia with a 75% accuracy.

Ex Output:

Is neoplastic progression in short-segment Barrett 's oesophagus associated with impairment of chemical clearance , but not inadequate acid suppression by proton pump inhibitor therapy?