267 research outputs found
Responsiveness of SF-36 Health Survey and Patient Generated Index in people with chronic knee pain commenced on oral analgesia: analysis of data from a randomised controlled clinical trial
Purpose. (1) to assess the responsiveness of the Short Form 36 Health Survey (SF-36) and Patient Generated Index (PGI) in people with knee pain who were given oral analgesics; and (2) to perform content analysis of the SF-36 and PGI aiming to identify differences between the instruments and causes of different responsiveness.
Methods. An observational study nested within a randomised controlled trial comparing oral paracetamol, ibuprofen or a combination of the two in 884 community-derived people with chronic knee pain. Each participant was given the SF-36 and PGI questionnaires to fill out at baseline, day 10, week 7 and week 13 after commencement on analgesia. Responsiveness was measured as a standardised response mean from baseline and contents of the instruments were analysed.
Results. The PGI showed the greater responsiveness to analgesics than the SF-36 throughout the study period. Only the Bodily Pain Score of the SF-36 showed comparable responsiveness to the PGI. The standardised response mean of the PGI at 13 weeks was 0.61 (95% confidence interval 0.51 to 0.72), and that of the Bodily Pain Score of the SF-36 was 0.49 (95% confidence interval 0.39 to 0.58). Content analysis of the PGI identified multiple areas which are not represented in the SF-36 which may help explain its performance.
Conclusions. Overall the PGI is more responsive than the SF-36 to commonly used oral analgesics taken for knee pain. The PGI is able to elicit areas of individualised health related quality of life which are not captured by the SF-36
Gender Differences in Aspirin use Among Adults With Coronary Heart Disease in the United States
BACKGROUND: Aspirin reduces mortality for men and women with coronary heart disease (CHD). Previous research suggests women with acute coronary syndromes receive less aggressive care, including less frequent early administration of aspirin. The presence of gender differences in aspirin use for secondary prevention is less clear. OBJECTIVE: To determine if a gender difference exists in the use of aspirin for secondary prevention among individuals with CHD. DESIGN: We analyzed data from the nationally representative 2000â2002 Medical Expenditure Panel Surveys to determine the prevalence of regular aspirin use among men and women with CHD. PARTICIPANTS: Participants, 1,869, 40Â years and older who reported CHD or prior myocardial infarction. RESULTS: Women were less likely than men to use aspirin regularly (62.4% vs 75.6%, pâ<â.001) even after adjusting for demographic, socioeconomic and clinical characteristics (adjusted ORâ=â0.62, 95% CI, 0.48â0.79). This difference narrowed but remained significant when the analysis was limited to those without self-reported contraindications to aspirin (79.8% vs 86.4%, Pâ=â.002, adjusted ORâ=â0.68, 95% CI, 0.48â0.97). Women were more likely than men to report contraindications (20.5% vs 12.5%, Pâ<â.001). Differences in aspirin use were greater between women and men with private health insurance (61.8% vs 79.0%, Pâ<â.001, adjusted ORâ=â0.48, 95% CI, 0.35â0.67) than among those with public coverage (62.5% vs 70.7%, Pâ=â.04, adjusted ORâ=â0.74, 95% CI, 0.50â1.11) (Pâ<â.001 for genderâinsurance interaction). CONCLUSION: We found a gender difference in aspirin use among patients with CHD not fully explained by differences in patient characteristics or reported contraindications. These findings suggest a need for improved secondary prevention of cardiovascular events for women with CHD
Search for post-merger gravitational waves from the remnant of the binary neutron star merger GW170817
In Advanced LIGO, detection and astrophysical source parameter estimation of the binary black hole merger GW150914 requires a calibrated estimate of the gravitational-wave strain sensed by the detectors. Producing an estimate from each detector's differential arm length control loop readout signals requires applying time domain filters, which are designed from a frequency domain model of the detector's gravitational-wave response. The gravitational-wave response model is determined by the detector's opto-mechanical response and the properties of its feedback control system. The measurements used to validate the model and characterize its uncertainty are derived primarily from a dedicated photon radiation pressure actuator, with cross-checks provided by optical and radio frequency references. We describe how the gravitational-wave readout signal is calibrated into equivalent gravitational-wave-induced strain and how the statistical uncertainties and systematic errors are assessed. Detector data collected over 38 calendar days, from September 12 to October 20, 2015, contain the event GW150914 and approximately 16 of coincident data used to estimate the event false alarm probability. The calibration uncertainty is less than 10% in magnitude and 10 degrees in phase across the relevant frequency band 20 Hz to 1 kHz
A search of the Orion spur for continuous gravitational waves using a "loosely coherent" algorithm on data from LIGO interferometers
We report results of a wideband search for periodic gravitational waves from
isolated neutron stars within the Orion spur towards both the inner and outer
regions of our Galaxy. As gravitational waves interact very weakly with matter,
the search is unimpeded by dust and concentrations of stars. One search disk
(A) is in diameter and centered on
, and the other
(B) is in diameter and centered on
. We explored the
frequency range of 50-1500 Hz and frequency derivative from to Hz/s. A multi-stage, loosely coherent search program allowed probing
more deeply than before in these two regions, while increasing coherence length
with every stage.
Rigorous followup parameters have winnowed initial coincidence set to only 70
candidates, to be examined manually. None of those 70 candidates proved to be
consistent with an isolated gravitational wave emitter, and 95% confidence
level upper limits were placed on continuous-wave strain amplitudes. Near
Hz we achieve our lowest 95% CL upper limit on worst-case linearly polarized
strain amplitude of , while at the high end of our
frequency range we achieve a worst-case upper limit of for
all polarizations and sky locations.Comment: Fixed minor typo - duplicate name in the author lis
First measurement of the Hubble Constant from a Dark Standard Siren using the Dark Energy Survey Galaxies and the LIGO/Virgo BinaryâBlack-hole Merger GW170814
International audienceWe present a multi-messenger measurement of the Hubble constant H 0 using the binaryâblack-hole merger GW170814 as a standard siren, combined with a photometric redshift catalog from the Dark Energy Survey (DES). The luminosity distance is obtained from the gravitational wave signal detected by the Laser Interferometer Gravitational-Wave Observatory (LIGO)/Virgo Collaboration (LVC) on 2017 August 14, and the redshift information is provided by the DES Year 3 data. Black hole mergers such as GW170814 are expected to lack bright electromagnetic emission to uniquely identify their host galaxies and build an object-by-object Hubble diagram. However, they are suitable for a statistical measurement, provided that a galaxy catalog of adequate depth and redshift completion is available. Here we present the first Hubble parameter measurement using a black hole merger. Our analysis results in , which is consistent with both SN Ia and cosmic microwave background measurements of the Hubble constant. The quoted 68% credible region comprises 60% of the uniform prior range [20, 140] km sâ1 Mpcâ1, and it depends on the assumed prior range. If we take a broader prior of [10, 220] km sâ1 Mpcâ1, we find (57% of the prior range). Although a weak constraint on the Hubble constant from a single event is expected using the dark siren method, a multifold increase in the LVC event rate is anticipated in the coming years and combinations of many sirens will lead to improved constraints on H 0
First narrow-band search for continuous gravitational waves from known pulsars in advanced detector data
In Advanced LIGO, detection and astrophysical source parameter estimation of the binary black hole merger GW150914 requires a calibrated estimate of the gravitational-wave strain sensed by the detectors. Producing an estimate from each detector's differential arm length control loop readout signals requires applying time domain filters, which are designed from a frequency domain model of the detector's gravitational-wave response. The gravitational-wave response model is determined by the detector's opto-mechanical response and the properties of its feedback control system. The measurements used to validate the model and characterize its uncertainty are derived primarily from a dedicated photon radiation pressure actuator, with cross-checks provided by optical and radio frequency references. We describe how the gravitational-wave readout signal is calibrated into equivalent gravitational-wave-induced strain and how the statistical uncertainties and systematic errors are assessed. Detector data collected over 38 calendar days, from September 12 to October 20, 2015, contain the event GW150914 and approximately 16 of coincident data used to estimate the event false alarm probability. The calibration uncertainty is less than 10% in magnitude and 10 degrees in phase across the relevant frequency band 20 Hz to 1 kHz
Searches for continuous gravitational waves from nine young supernova remnants
We describe directed searches for continuous gravitational waves in data from
the sixth LIGO science data run. The targets were nine young supernova remnants
not associated with pulsars; eight of the remnants are associated with
non-pulsing suspected neutron stars. One target's parameters are uncertain
enough to warrant two searches, for a total of ten. Each search covered a broad
band of frequencies and first and second frequency derivatives for a fixed sky
direction. The searches coherently integrated data from the two LIGO
interferometers over time spans from 5.3-25.3 days using the matched-filtering
F-statistic. We found no credible gravitational-wave signals. We set 95%
confidence upper limits as strong (low) as on intrinsic
strain, on fiducial ellipticity, and on
r-mode amplitude. These beat the indirect limits from energy conservation and
are within the range of theoretical predictions for neutron-star ellipticities
and r-mode amplitudes.Comment: Science summary available at
http://www.ligo.org/science/Publication-S6DirectedSNR/index.ph
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