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.

[Q]: Context: Therapeutic and prophylactic vena cava filters (VCFs) are used to prevent pulmonary embolism. Concerns exist over placing a permanent filter in a young trauma patient. Recently, retrievable VCFs have become available. One such filter is the OptEase, which has a recommended time of removal of up to 23 days after insertion. Data supporting this recommendation are sparse. Many trauma patients will need filters for more than 2 weeks, and there are no data evaluating the safety of removal after extended time periods. The purpose of this study was to determine the safety, feasibility, and reaction of the vena cava when removing the OptEase retrievable VCF at different time intervals.', 'Twenty Yorkshire cross pigs (80-113 kg) underwent general anesthesia with tiletamine and zolazepam. Filters were placed in the infrarenal vena cava (VC) through the femoral vein under fluoroscopic guidance. Animals were then divided into four groups. In group 1, filters were removed at 14 days; in group 2, at 30 days; in group 3, at 60 days; and in group 4, at 90 days. Removal was attempted using a snare-and-sheath technique through the femoral vein. Animals with successful filter removal were allowed to recover; then, the animals underwent autopsy (gross and microscopic VC examination) 2 months later. Animals with unsuccessful filter removal underwent autopsy immediately after attempted removal. Venacavograms were taken at filter insertion, at removal, and before autopsy to evaluate any VC abnormalities.', 'Successful removal of the filter in all five pigs (100%) was reliably performed only in the 14-day group. In this group, the initial VC transverse diameter was 19.4 +/- 0.8 mm and was significantly reduced to 9.8 +/- 1.1 mm (p < 0.05) immediately after removal. Sixty days later, before autopsy, VC diameter had increased to 15.3 +/- 1.9 mm, which was significantly larger than at removal (p < 0.05) but not different from the initial value. In the 30-day group, removal was successful in only one of five animals. Although removal was successful in the one pig, autopsy at 2 months postremoval revealed total occlusion of the VC. Filters could not be removed from 60- and 90-day groups. At autopsy, the VCF struts were embedded or protruded through the VC wall. Microscopic examination of the VC revealed significant scarring underneath and between the struts.\Question: Is removal of the OptEase retrievable vena cava filter feasible after extended time periods because of filter protrusion through the vena cava?
[A]: Removal of the retrievable OptEase VCF may be successfully performed up to 14 days after insertion. Strut protrusion through the VC wall prohibited successful and safe removal at extended time intervals.


[Q]: Context: To investigate the prognostic value of the pre-treatment haemoglobin level in patients with advanced squamous cell head and neck cancer treated with induction polychemotherapy.', 'Seventy-two patients with advanced squamous cell head and neck cancer received primary combination chemotherapy consisting of docetaxel 75 mg/m(2) on day 1, cisplatin 100 mg/m(2) on day 1, and 5-fluorouracil (5-FU) 1000 mg/m(2)/day on days 1-4 (total dose 4000 mg/m(2)), repeated on days 1, 22 and 43 followed by chemoradiation. The data collected included pre-treatment haemoglobin, response to treatment, disease-free and overall survival.', 'The pre-treatment haemoglobin level was found to be a significant predictor of response to induction chemotherapy (P = 0.01) and an independent predictor of overall survival [hazard ratio (HR) 0.77, 95% confidence interval (CI) 0.58-1.03, P = 0.0001] and disease free survival (HR 2.09, 95% CI 1.41-3.09, P = 0.0001). Furthermore N-stage was found to be a significant prognostic factor of overall survival (HR 9.24, 95% CI 6.90-21.34, P = 0.005). The Eastern Cooperative Oncology Group performance status scale was also found to be significant for disease free survival (HR 7.66, 95% CI 2.61-22.46, P = 0.003).\Question: Does pre-treatment haemoglobin level predict response and survival after TPF induction polychemotherapy in advanced head and neck cancer patients?
[A]: In patients with advanced squamous cell head and neck cancer, the haemoglobin level prior to induction chemotherapy is significantly related to outcome including response and survival.


[Q]: Context: It is recommended that dentists screen for dental anxiety (DA) so that fearful patients may be better managed. The main aim of this study was to determine what dentists are being taught in relation to DA as well as whether and how anxious patients are identified in the clinic.', 'Two hundred and forty-six practising dentists (adjusted response rate = 40.1%), from a random sample of registered Australian dentists, completed a mailed questionnaire.', "Dentists estimated that high DA affected 23.3% of children and 19.4% of adults seen. Only 3.7% of dentists reported using a published scale for screening DA, with the most common reason being lack of awareness (56.5%). Approximately one-half of responding dentists directly asked their patients about DA and this was more common among younger dentists (χ(2) = 7.75, p = 0.021). There were few differences in DA screening by other practitioner or practice characteristics (p > 0.05). Only one-third of dentists had received undergraduate training related to DA and only 41.7% considered this to be 'good' or better. Almost 37% of respondents expressed an interest in future training opportunities.\Question: Does dental anxiety screening practices and self-reported training need among Australian dentists?
[A]:
The use of formal, validated scales for screening DA is minimal. Training in anxiety management appears to be low and is an area that could be expanded upon.