Osteoporosis in the community. Sensitivity of self-reported estimates and medication use of those diagnosed with the condition

Objectives: To assess the sensitivity and specificity of self-reported osteoporosis compared with dual energy X-ray absorptiometry (DXA) defined osteoporosis, and to describe medication use among participants with the condition. Methods: Data were obtained from a population-based longitudinal study and assessed for the prevalence of osteoporosis, falls, fractures and medication use. DXA scans were also undertaken. Results: Overall 3.8% (95% confidence interval (CI) 3.2 to 4.5) of respondents and 8.8% (95% CI 7.5 to 10.3) of those aged ≥ 50 years reported that they had been diagnosed with osteoporosis by a doctor. The sensitivity (those self-reporting osteoporosis and having low bone mineral density (BMD) on DXA) was low (22.7%), although the specificity was high (94.4%). Only 16.1% of those aged ≥ 50 years and with DXA-defined osteoporosis were taking bisphosphonates. Conclusions: The sensitivity of self-reporting to identify osteoporosis is low. Anti-osteoporotic medications are an important part of osteoporosis treatment but opportunities to use appropriate medications were missed and inappropriate medications were used.T. K. Gill, A. W. Taylor, C. L. Hill, P. J. Phillip

Validation and comparative evaluation of the osteoporosis self-assessment tool (OST) in a Caucasian population from Belgium

BACKGROUND: Risk indices have been developed to identify women at risk of low bone mineral density (BMD) who should undergo BMD testing. Aim: To compare the performance of four risk indices in White ambulatory women in Belgium. DESIGN: Epidemiological cross-sectional study. METHODS: Records were analysed for 4035 postmenopausal White women without Paget's disease or advanced osteoarthritis, seen at an out-patient osteoporosis centre between January 1996 and September 1999. Osteoporosis risk index scores were compared to bone density T-scores. The ability of each risk index to identify women with low BMD (T-score < -2.0) or osteoporosis (T < -2.5) was evaluated. RESULTS: Using an Osteoporosis Self-Assessment Tool (OST) score <2 to recommend DXA referral, sensitivity ranged from 85% at the lumbar spine to 97% at the total hip to detect BMD T-scores of <or= -2.5, and specificity ranged from 34% at the total hip to 37% at the femoral neck and lumbar spine. The negative predictive value was high at all skeletal sites (89-99%), demonstrating the usefulness of the OST to identify patients who have normal BMD and should not receive DXA testing. All risk indices performed similarly, although the OST had somewhat better sensitivity and somewhat lower specificity than the other indices at the cut-offs evaluated. Among the 11-12% of women who were classified as highest risk using OST or the Osteoporosis Index of Risk (OSIRIS), 81-85% had low bone mass and 68-74% had osteoporosis. DISCUSSION: The performance of these risk indices among women in Belgium was similar to that reported earlier for other samples in Asian countries, the US, and the Netherlands. The OST and other risk indices are effective and efficient tools to help target high-risk women for DXA testing

Infrared to vacuum-ultraviolet ellipsometry and optical Hall-effect study of free-charge carrier parameters in Mg-doped InN

Infrared to vacuum-ultraviolet spectroscopic ellipsometry and far-infrared optical Hall-effect measurements are applied to conclude on successful p-type doping of InN films. A representative set of In-polar Mg-doped InN films with Mg concentrations ranging from 1.2 x 10(16) cm(-3) to 3.9 x 10(21) cm(-3) is investigated. The data are compared and discussed in dependence of the Mg concentration. Differences between n-type and p-type conducting samples are identified and explained. p-type conductivity in the Mg concentration range between 1.1 x 10(18) cm(-3) and 2.9 x 10(19) cm(-3) is indicated by the appearance of a dip structure in the infrared spectral region related to a loss in reflectivity of p-polarized light as a consequence of reduced LO phonon plasmon coupling, by vanishing free-charge carrier induced birefringence in the optical Hall-effect measurements, and by a sudden change in phonon-plasmon broadening behavior despite continuous change in the Mg concentration. By modeling the near-infrared-to-vacuum-ultraviolet ellipsometry data, information about layer thickness, electronic interband transitions, as well as surface roughness is extracted in dependence of the Mg concentration. A parameterized model that accounts for the phonon-plasmon coupling is applied for the infrared spectral range to determine the free-charge carrier concentration and mobility parameters in the doped bulk InN layer as well as the GaN template and undoped InN buffer layer. The optical Hall-effect best-match model parameters are consistent with those obtained from infrared ellipsometry analysis.Funding Agencies|National Science Foundation|MRSEC DMR-0820521MRI DMR-0922937DMR-0907475EPS-1004094|Swedish Research Council (VR)|2010-3848|Swedish Governmental Agency for Innovation Systems (VINNOVA) under the VINNMER International Qualification program|2011-03486|FCT Portugal|PTDC/FIS/100448/2008|</p