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.

Example Input: Results from GOG 178 showed a prolongation of progression-free survival (PFS) with the immediate use of chemotherapy (CT) following a complete clinical response (CR) in patients with stage III-IV ovarian cancer. We wanted to evaluate our strategy of reserving second line (2nd line) chemotherapy to the time of clinical recurrence by determining PFS intervals following first, second, and third line agents and to compare these finding to results of GOG 178.', 'We conducted a retrospective parallel study to GOG 178 using identical criteria for PFS definitions. Patients (pts) with stage III-IV cancer achieving a CR following surgery and five to eight cycles of platinum-based CT were identified. Patients not obtaining a CR and those with a CR who underwent second look surgery were excluded. Rather than immediately beginning consolidation CT after CR, second line agents were started at recurrence and were followed by a third line when pts progressed. Clinical-pathologic characteristics were abstracted, and time intervals including time to recurrence, time to use of second line CT, time to use of third line (3rd line) CT, and survival were recorded. Time intervals were studied by Kaplan-Meier method.', 'Of 217 reviewed pts (1991-2001), 59 eligible pts were identified. Forty-nine patients had stage III disease and ten had stage IV. At completion of surgery, 44 were optimally debulked. With a median follow-up of 51 months, the median PFS (from CR) of all patients was 20 months. At 5 years, 36% of pts remain disease-free, and 66% of pts are alive. Twenty-three pts have not received second line agents, and thirty-six have received them. For all pts, the median time from CR to start of second line chemotherapy was 21 months, and the median time to start of third line agents was 43 months. Recurrences occurred after 6 months from completion of first line (1st line) therapy in 87% of cases and after 12 months in 50%.
Example Output: Is timing n't everything : an analysis of when to start salvage chemotherapy in ovarian cancer?

Example Input: The purpose of this study is to examine the effect of insurance coverage on stage of presentation, treatment, and survival of head and neck cancer (HNC).', 'A retrospective study was conducted using the Surveillance, Epidemiology, and End Results (SEER) program to identify patients diagnosed with HNC. The primary variable of interest was insurance analyzed as a dichotomous variable: Patients were considered uninsured if they were classified as "uninsured" by SEER, whereas patients were considered insured if they were defined by SEER as "any Medicaid," "insured," or "insured/no specifics." The outcomes of interest were cancer stage at presentation (M0 vs M1), receipt of definitive treatment, and HNC-specific mortality (HNCSM). Multivariable logistic regression modeled the association between insurance status and stage at presentation, as well as between insurance status and receipt of definitive treatment, whereas HNCSM was modeled using Fine and Gray competing risks. Sensitivity logistic regression analysis was used to determine whether observed interactions remained significant by insurance type (privately insured, Medicaid, and uninsured).', 'Patients without medical insurance were more likely to present with metastatic cancer (adjusted odds ratio, 1.60; P < .001), were more likely to not receive definitive treatment (adjusted odds ratio, 1.64; P < .001), and had a higher risk of HNCSM (adjusted hazard ratio, 1.20; P= .002). Sensitivity analyses showed that when results were stratified by insurance type, significant interactions remained for uninsured patients and patients with Medicaid.
Example Output: Does health Insurance affect Head and Neck Cancer Treatment Patterns and Outcomes?

Example Input: To investigate the independent relationship of individual- and area-level socio-economic status (SES) with the presence and severity of visual impairment (VI) in an Asian population.', 'Cross-sectional data from 9993 Chinese, Malay and Indian adults aged 40-80 years who participated in the Singapore Epidemiology of eye Diseases (2004-2011) in Singapore. Based on the presenting visual acuity (PVA) in the better-seeing eye, VI was categorized into normal vision (logMAR0.30), low vision (logMAR>0.30<1.00), and blindness (logMAR1.00). Any VI was defined as low vision/blindness in the PVA of better-seeing eye. Individual-level low-SES was defined as a composite of primary-level education, monthly income<2000 SGD and residing in 1 or 2-room public apartment. An area-level SES was assessed using a socio-economic disadvantage index (SEDI), created using 12 variables from the 2010 Singapore census. A high SEDI score indicates a relatively poor SES. Associations between SES measures and presence and severity of VI were examined using multi-level, mixed-effects logistic and multinomial regression models.', 'The age-adjusted prevalence of any VI was 19.62% (low vision = 19%, blindness = 0.62%). Both individual- and area-level SES were positively associated with any VI and low vision after adjusting for confounders. The odds ratio (95% confidence interval) of any VI was 2.11(1.88-2.37) for low-SES and 1.07(1.02-1.13) per 1 standard deviation increase in SEDI. When stratified by unilateral/bilateral categories, while low SES showed significant associations with all categories, SEDI showed a significant association with bilateral low vision only. The association between low SES and any VI remained significant among all age, gender and ethnic sub-groups. Although a consistent positive association was observed between area-level SEDI and any VI, the associations were significant among participants aged 40-65 years and male.
Example Output:
Do composite Measures of Individual and Area-Level Socio-Economic Status Are Associated with Visual Impairment in Singapore?