In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.
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Question: Context: To assess how different imputation methods used to account for missing variance data in primary studies influence tests of heterogeneity and pooled results from a meta-analysis with continuous outcomes.', 'Point and variance estimates for changes in serum creatinine, glomerular filtration rate, systolic blood pressure, and diastolic blood pressure were variably reported among 48 primary longitudinal studies of living kidney donors (71%-78% of point estimates were reported, 8%-13% of variance data were reported). We compared the results of meta-analysis, which either were restricted to available data or used four methods to impute missing variance data. These methods used reported P-values, reported nonparametric summaries, results from other similar studies using multiple imputation, or results from estimated correlation coefficients.', 'Significant heterogeneity was present in all four outcomes regardless of the imputation methods applied. The random effects point estimates and 95% confidence intervals varied little across imputation methods, and the differences were not clinically significant.\Question: Do imputing variance estimates alter the conclusions of a meta-analysis with continuous outcomes : a case study of changes in renal function after living kidney donation?

Answer: Different methods to impute the variance data in the primary studies did not alter the conclusions from this meta-analysis of continuous outcomes. Such reproducibility increases confidence in the results. However, as with most meta-analyses, there was no gold standard of truth, and results must be interpreted judiciously. The generalization of these findings to other meta-analyses, which differ in outcomes, missing data, or between-study heterogeneity, requires further consideration.

Question: Context: To test the hypothesis that effective pulmonary capillary blood flow can be a useful indicator for estimating appropriate oxygenation and ventilation during one-lung ventilation in lung surgery.', 'Prospective data analysis.', 'A 770-bed general teaching hospital.', '15 ASA physical status II and III patients undergoing elective lung surgery.', 'Patients received general and thoracic epidural anesthesia and underwent lung operation with one-lung ventilation.', 'We measured effective pulmonary capillary blood flow by a partial CO2 rebreathing method and oxygenation parameters during two-lung ventilation before surgery, during one-lung ventilation, and during two-lung ventilation after lung surgery.', 'The effective pulmonary capillary blood flow index significantly decreased by 31.6%, which was associated with a significant decrease in arterial oxygen tension (PaO2). The pulmonary shunt fraction increased to 46.3% during one-lung ventilation. During two-lung ventilation, after chest closure, effective pulmonary capillary blood flow index divided by heart rate (i.e., effective pulmonary blood stroke flow index) was still significantly lower than that seen during two-lung ventilation before thoracotomy. There were significant correlations between effective pulmonary capillary blood flow, pulmonary blood stroke flow index, and PaO2.\Question: Is a noninvasive partial carbon dioxide rebreathing technique for measurement of pulmonary capillary blood flow also a useful oxygenation monitor during one-lung ventilation?

Answer: Effective pulmonary capillary blood flow index and effective pulmonary blood stroke flow index are useful indicators for determining appropriate oxygenation therapy during one-lung ventilation.

Question: Context: To determine the prevalence of haemorrhoids in women with pelvic vein reflux, identify which pelvic veins are associated with haemorrhoids and assess if extent of pelvic vein reflux influences the prevalence of haemorrhoids.', 'Females presenting with leg varicose veins undergo duplex ultrasonography to assess all sources of venous reflux. Those with significant reflux arising from the pelvis are offered transvaginal duplex ultrasound (TVS) to evaluate reflux in the ovarian veins and internal Iliac veins and associated pelvic varices in the adnexa, vulvar/labial veins and haemorrhoids. Patterns and severity of reflux were evaluated.', 'Between January 2010 and December 2012, 419 female patients with leg or vulvar varicose vein patterns arising from the pelvis underwent TVS. Haemorrhoids were identified on TVS via direct tributaries from the internal Iliac veins in 152/419 patients (36.3%) and absent in 267/419 (63.7%). The prevalence of the condition increased with the number of pelvic trunks involved.\Question: Are haemorrhoids associated with internal iliac vein reflux in up to one-third of women presenting with varicose veins associated with pelvic vein reflux?

Answer:
There is a strong association between haemorrhoids and internal Iliac vein reflux. Untreated reflux may be a cause of subsequent symptomatic haemorrhoids. Treatment with methods proven to work in conditions caused by pelvic vein incompetence, such as pelvic vein embolisation and foam sclerotherapy, could be considered.