Karen Horn Welch

Learn More
A new data set of on openness indicators and trade liberalization dates allows the 1995 Sachs and Warner study on the relationship between trade openness and economic growth to be extended to the 1990s. New evidence on the time paths of economic growth, physical capital investment, and openness around episodes of trade policy liberalization is also(More)
BACKGROUND To assess the effects of patient education on mortality, morbidity, health-related quality of life (HRQoL), and healthcare costs in people with coronary heart disease (CHD). DESIGN Systematic review and meta-analysis. METHODS Data sources were Cochrane Library, Medline, Embase, PsycINFO, CINAHL, and ongoing trial registries until August 2010.(More)
OBJECTIVES To identify the psychological effects of false-positive screening mammograms in the UK. METHODS Systematic review of all controlled studies and qualitative studies of women with a false-positive screening mammogram. The control group participants had normal mammograms. All psychological outcomes including returning for routine screening were(More)
OBJECTIVES To estimate the cost-effectiveness of temsirolimus compared to interferon-alpha for first line treatment of patients with advanced, poor prognosis renal cell carcinoma, from the perspective of the UK National Health Service. METHODS A decision-analytic model was developed to estimate the cost-effectiveness of temsirolimus. The clinical(More)
BACKGROUND Peripheral arterial disease (PAD) is frequently treated by either an infrainguinal autologous (using the patient's own veins) or synthetic graft bypass. The rate of occlusion of the graft after one year is between 12% and 60%. To prevent occlusion, patients are treated with an antiplatelet or antithrombotic drug, or a combination of both. Little(More)
OBJECTIVES The authors developed a tool to assess the quality of search filters designed to retrieve records for studies with specific research designs (e.g., diagnostic studies). METHODS The UK InterTASC Information Specialists' Sub-Group (ISSG), a group of experienced health care information specialists, reviewed the literature to evaluate existing(More)
Mozambique liberalized its cashew sector in the early 1990s in response to pressure from the World Bank. Opponents of the reform have argued that the policy did little to benefit poor cashew farmers while bankrupting factories in urban areas. Using a welfaretheoretic framework, we analyze the available evidence and provide an accounting of the(More)
OBJECTIVES To estimate the cost-effectiveness of sorafenib (Nexavar, Bayer, Leverkusen, Germany) versus best supportive care (BSC) for second-line treatment of advanced renal cell carcinoma from the perspective of the UK National Health Service. METHODS A decision analytic model was developed to estimate the cost-effectiveness of sorafenib. The clinical(More)
Patients that are exposed to biotechnology-derived therapeutics often develop antibodies to the therapeutic, the magnitude of which is assessed by measuring antibody titers. A statistical approach for analyzing antibody titer data conditional on seroconversion is presented. The proposed method is to first transform the antibody titer data based on a(More)
BACKGROUND Pulmonary embolism (PE) can occur when a thrombus (blood clot) travels through the veins and lodges in the arteries of the lungs, producing an obstruction. People who are thought to be at risk include those with cancer, people who have had a recent surgical procedure or have experienced long periods of immobilisation and women who are pregnant.(More)