38 research outputs found
Geographic Variability in Access to Primary Kidney Transplantation in the United States, 1996–2005
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75057/1/j.1600-6143.2007.01785.x.pd
Who should be prioritized for renal transplantation?: Analysis of key stakeholder preferences using discrete choice experiments
Background
Policies for allocating deceased donor kidneys have recently shifted from allocation based on Human Leucocyte Antigen (HLA) tissue matching in the UK and USA. Newer allocation algorithms incorporate waiting time as a primary factor, and in the UK, young adults are also favoured. However, there is little contemporary UK research on the views of stakeholders in the transplant process to inform future allocation policy. This research project aimed to address this issue.
Methods
Discrete Choice Experiment (DCE) questionnaires were used to establish priorities for kidney transplantation among different stakeholder groups in the UK. Questionnaires were targeted at patients, carers, donors / relatives of deceased donors, and healthcare professionals. Attributes considered included: waiting time; donor-recipient HLA match; whether a recipient had dependents; diseases affecting life expectancy; and diseases affecting quality of life.
Results
Responses were obtained from 908 patients (including 98 ethnic minorities); 41 carers; 48 donors / relatives of deceased donors; and 113 healthcare professionals. The patient group demonstrated statistically different preferences for every attribute (i.e. significantly different from zero) so implying that changes in given attributes affected preferences, except when prioritizing those with no rather than moderate diseases affecting quality of life. The attributes valued highly related to waiting time, tissue match, prioritizing those with dependents, and prioritizing those with moderate rather than severe diseases affecting life expectancy. Some preferences differed between healthcare professionals and patients, and ethnic minority and non-ethnic minority patients. Only non-ethnic minority patients and healthcare professionals clearly prioritized those with better tissue matches.
Conclusions
Our econometric results are broadly supportive of the 2006 shift in UK transplant policy which emphasized prioritizing the young and long waiters. However, our findings suggest the need for a further review in the light of observed differences in preferences amongst ethnic minorities, and also because those with dependents may be a further priority.</p
Advancing Tests of Relativistic Gravity via Laser Ranging to Phobos
Phobos Laser Ranging (PLR) is a concept for a space mission designed to
advance tests of relativistic gravity in the solar system. PLR's primary
objective is to measure the curvature of space around the Sun, represented by
the Eddington parameter , with an accuracy of two parts in ,
thereby improving today's best result by two orders of magnitude. Other mission
goals include measurements of the time-rate-of-change of the gravitational
constant, and of the gravitational inverse square law at 1.5 AU
distances--with up to two orders-of-magnitude improvement for each. The science
parameters will be estimated using laser ranging measurements of the distance
between an Earth station and an active laser transponder on Phobos capable of
reaching mm-level range resolution. A transponder on Phobos sending 0.25 mJ, 10
ps pulses at 1 kHz, and receiving asynchronous 1 kHz pulses from earth via a 12
cm aperture will permit links that even at maximum range will exceed a photon
per second. A total measurement precision of 50 ps demands a few hundred
photons to average to 1 mm (3.3 ps) range precision. Existing satellite laser
ranging (SLR) facilities--with appropriate augmentation--may be able to
participate in PLR. Since Phobos' orbital period is about 8 hours, each
observatory is guaranteed visibility of the Phobos instrument every Earth day.
Given the current technology readiness level, PLR could be started in 2011 for
launch in 2016 for 3 years of science operations. We discuss the PLR's science
objectives, instrument, and mission design. We also present the details of
science simulations performed to support the mission's primary objectives.Comment: 25 pages, 10 figures, 9 table
Comparison of quality-of-care measures in U.S. patients with end-stage renal disease secondary to lupus nephritis vs. other causes
BACKGROUND: Patients with end-stage renal disease (ESRD) due to lupus nephritis (LN-ESRD) may be followed by multiple providers (nephrologists and rheumatologists) and have greater opportunities to receive recommended ESRD-related care. We aimed to examine whether LN-ESRD patients have better quality of ESRD care compared to other ESRD patients. METHODS: Among incident patients (7/05–9/11) with ESRD due to LN (n = 6,594) vs. other causes (n = 617,758), identified using a national surveillance cohort (United States Renal Data System), we determined the association between attributed cause of ESRD and quality-of-care measures (pre-ESRD nephrology care, placement on the deceased donor kidney transplant waitlist, and placement of permanent vascular access). Multivariable logistic and Cox proportional hazards models were used to estimate adjusted odds ratios (ORs) and hazard ratios (HRs). RESULTS: LN-ESRD patients were more likely than other ESRD patients to receive pre-ESRD care (71% vs. 66%; OR = 1.68, 95% CI 1.57-1.78) and be placed on the transplant waitlist in the first year (206 vs. 86 per 1000 patient-years; HR = 1.42, 95% CI 1.34–1.52). However, only 24% had a permanent vascular access (fistula or graft) in place at dialysis start (vs. 36%; OR = 0.63, 95% CI 0.59–0.67). CONCLUSIONS: LN-ESRD patients are more likely to receive pre-ESRD care and have better access to transplant, but are less likely to have a permanent vascular access for dialysis, than other ESRD patients. Further studies are warranted to examine barriers to permanent vascular access placement, as well as morbidity and mortality associated with temporary access, in patients with LN-ESRD
The Confrontation between General Relativity and Experiment
The status of experimental tests of general relativity and of theoretical
frameworks for analysing them is reviewed. Einstein's equivalence principle
(EEP) is well supported by experiments such as the Eotvos experiment, tests of
special relativity, and the gravitational redshift experiment. Future tests of
EEP and of the inverse square law are searching for new interactions arising
from unification or quantum gravity. Tests of general relativity at the
post-Newtonian level have reached high precision, including the light
deflection, the Shapiro time delay, the perihelion advance of Mercury, and the
Nordtvedt effect in lunar motion. Gravitational-wave damping has been detected
in an amount that agrees with general relativity to better than half a percent
using the Hulse-Taylor binary pulsar, and other binary pulsar systems have
yielded other tests, especially of strong-field effects. When direct
observation of gravitational radiation from astrophysical sources begins, new
tests of general relativity will be possible.Comment: 89 pages, 8 figures; an update of the Living Review article
originally published in 2001; final published version incorporating referees'
suggestion
Trends in Organ Donation and Transplantation in the United States, 1996–2005
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/71697/1/j.1600-6143.2007.01778.x.pd