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.

Input: Consider Input: Bilateral lower extremity venous duplex scanning for acute deep venous thrombosis (DVT) has been advocated because of the high incidence of occult contralateral leg involvement. We investigated the clinical necessity of such a policy.', 'The results from 2996 venous duplex studies performed during the past 2 years were retrospectively reviewed. A total of 1694 of these scans were performed on patients with symptoms, of whom 248 (15%) were found to have an acute DVT. Symptoms were limited to one side in 198 patients, whereas bilateral complaints were noted in 50 patients.', 'Among the patients with symptoms of acute DVT, 72 (29%) had bilateral involvement. Bilaterality was more likely in patients with bilateral symptoms than in those with only unilateral symptoms (56% vs 22%; p < 0.005). Of the patients with unilateral symptoms and bilateral DVT, all of them had either acute (80%) or acute and chronic (20%) thrombosis in the symptomatic leg. The contralateral asymptomatic limb had fewer acute and more chronic DVT (41% and 55%, respectively). No patient from the entire group admitted with symptoms had an acute DVT in the asymptomatic limb without a concomitant acute DVT in the symptomatic leg. Unilateral scanning would decrease the examination time by 21% and potentially increase total reimbursement for symptomatic venous scans by 9% compared with routine bilateral duplex scanning.

Output: Is contralateral duplex scanning for deep venous thrombosis unnecessary in patients with symptoms?


Input: Consider 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.

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


Input: Consider Input: To investigate the prevalence and temporal development of N-methyl-d-aspartate receptor (NMDAR) autoantibodies in relation to neurocognitive performance in patients with herpes simplex encephalitis (HSE).', "This prospective observational study enrolled a total of 49 HSE patients within a randomized controlled trial of valacyclovir. Cerebrospinal fluid and serum samples were drawn in the initial stage of disease, after 2 to 3\xa0weeks and after 3\xa0months. Anti-NMDAR IgG was detected with HEK293\xa0cells transfected with plasmids encoding the NMDA NR1 type glutamate receptor. A batch of neurocognitive tests, including the Mattis Dementia Rating Scale (MDRS), Glasgow Coma Scale (GCS), Reaction Level Scale (RLS85), Mini-Mental State Examination (MMSE) and National Institutes of Health (NIH) stroke scale, was performed during 24\xa0months' follow-up.", "Anti-NMDAR IgG was detected in 12 of 49 participants. None were antibody positive in the initial stage of disease. In ten of 12 positive cases, specific antibodies were detectable only after 3\xa0months. Notably, the development of NMDAR autoantibodies was associated with significantly impaired recovery of neurocognitive performance. After 24\xa0months' follow-up, the median increase in MDRS total score was 1.5 vs. 10 points in antibody-positive and -negative participants (p=0.018).


Output: Does n-methyl-d-aspartate receptor autoimmunity affect cognitive performance in herpes simplex encephalitis?