Determining the Health Utility of Urinary Incontinence in Women

Objective The goal of this study was to define the utility of urinary incontinence in women using the Standard Gamble, the gold standard method for determining health state utilities, based on a diagnosis obtained from multichannel urodynamic testing, the gold standard in clinical diagnosis. Background Health state utility values are important in many areas of medical research. The values are used in cost-utility analysis, decision analysis and health related quality of life studies. To date, studies that have estimated the utility of urinary incontinence in women have relied on values from generic health related quality of life questionnaires such as the ED-5Q and Health Utilities Index or from expert opinion. The utility of urinary incontinence in these studies appears to be unintuitivelylow, at 0.71 to 0.82, with perfect health represented by 1.0. The utility of health states that are much more debilitating, for example cancer (0.82), is higher than urinary incontinence. These studies have relied on patient self-diagnosis of incontinence. Additionally, they have considered all types of urinary incontinence together. Intuitively, one would think that quality of life would be affected differently with different types (stress, urge, mixed) and differing severity of incontinence. Methods All adult female patients who underwent urodynamic testing at Brigham and Women’s Hospital were prospectively recruited. Diagnosis of type of incontinence was made by attending physician interpretation of the urodynamic study. No exclusion criteria. Patients completed three validated questionnaires: Sandvik Severity Index - A validated two question symptom specific instrument to evaluate urinary incontinence EQ-5D -A five-domain generic quality of life questionnaire. Answers are converted into a utility value. Visual Analog Scale - Vertical line from 0 (worst imaginable health) to 100 (best imaginable health). Patient rates own perception of health on line. The Standard Gamble technique was used in a standard format to determine each patient’s utility value for their health state. Patient is asked to choose between life in current health state and varying risks of immediate painless death. Gold Standard method to determine patients utility preference for their health state. Results This pilot study of 28 patients demonstrated a significant difference in utility value derived from the Standard Gamble and the generic health-related quality of life instruments. There were 21 patients with stress urinary incontinence, 6 patients with urge urinary incontinence and 1 patient with mixed urinary incontinence. Mean Sandvik score was higher in Urge Incontinence subgroup. Mean Utility from Standard Gamble was lower in Urge Incontinence group. Sandvik scores were moderately correlated with EQ-5D, SG and VAS utilities. Conclusions Utility scores derived from Standard Gamble were significantly higher than those derived from generic health related quality of life instruments. Utility scores derived from EQ-5D and VAS were similar tothose previously reported in the literature. Current utility values over-estimate the degree of bother of urinary incontinence. Researchers should consider using higher utility values for urinary incontinence in future cost utility and quality of life studies

Understanding Health Utilities in Women with Urinary Incontinence

Objectives: The purpose of this study was to compare the health utility of UI in women as derived from the EQ-5D with the gold standard, the Standard Gamble. The secondary aim of this study was to compare health utility values of affected patients to healthy controls. Materials and Methods: Clinical diagnosis was categorized as normal, stress, mixed or urge urinary incontinence. Healthy controls were read a scenario for stress or mixed UI. All subjects completed the Sandvik Severity Index (SSI), EQ-5D, and Standard Gamble (SG) conversation. Results: 50 healthy controls and 119 affected subjects were recruited. The mean utility value for incontinence varied based on method: EQ-5D (0.78 + 0.17) and SG (0.85 + 0.20). There was a significant difference between utility scores derived from SG and EQ-5D (p=0.0004). This significant difference was maintained in the subset of women with SUI: EQ-5D (0.81 + 0.16), SG (0.87 + 0.18), p=0.028; but not in women with MUI or UUI. When comparing healthy controls to women with SUI, there were significant differences in the utility values derived by SG (0.76 + 0.26 vs. 0.87 + 0.18, p=0.07) but not by EQ-5D. When comparing healthy controls to women with MUI, there was also a significant difference in the utility derived by SG (0.92 + 0.10 vs. 0.75 + 0.21, p=0.01) but not by EQ-5D. SSI scores moderately correlated with SG utility values and strongly correlated with EQ-5D utility values. Logistic regression analysis showed that utility values were unaffected by age and menopausal status. Conclusion: This study suggests that using the EQ-5D to quantify the utility of UI may over-estimate the degree of bother when compared to SG assessment. This is important because the SG process more closely approximates the decision to undergo surgery. Relying on the EQ-5D to assess health utilities in women with UI may not be valid

Further investigations of the deep double donor magnesium in silicon

The deep double donor levels of substitutional chalcogen impurities in silicon have unique optical properties which may enable a spin/photonic quantum technology. The interstitial magnesium impurity (Mg$_i$) in silicon is also a deep double donor but has not yet been studied in the same detail as have the chalcogens. In this study we look at the neutral and singly ionized Mg$_i$ absorption spectra in natural silicon and isotopically enriched 28-silicon in more detail. The 1s(A$_1$) to 1s(T$_2$) transitions, which are very strong for the chalcogens and are central to the proposed spin/photonic quantum technology, could not be detected. We observe the presence of another double donor (Mg$_{i*}$) that may result from Mg$_i$ in a reduced symmetry configuration, most likely due to complexing with another impurity. The neutral species of Mg$_{i*}$ reveal unusual low lying ground state levels detected through temperature dependence studies. We also observe a shallow donor which we identify as a magnesium-boron pair

A Mg-pair isoelectronic bound exciton identified by its isotopic fingerprint in 28^{28}Si

We use the greatly improved optical linewidths provided by highly enriched $^{28}$Si to study a photoluminescence line near 1017 meV previously observed in the luminescence spectrum of natural Si diffused with Mg, and suggested to result from the recombination of an isoelectronic bound exciton localized at a Mg-pair center. In $^{28}$Si this no-phonon line is found to be comprised of five components whose relative intensities closely match the relative abundances of Mg-pairs formed by random combinations of the three stable isotopes of Mg, thus confirming the Mg-pair hypothesis. We further present the results of temperature dependence studies of this center that reveal unusual and as yet unexplained behaviour.Comment: 5 pages, 4 figure

Microwave Electronics

Contains research objectives and reports on two research projects.U. S. Air Force under Air Force Contract AF19(604)-5200U. S. Navy (Office of Naval Research) under Contract Nonr-1841(49)U. S. NavyU. S. ArmyLincoln Laboratory, Purchase Order DDL B-0030

The Statistical Mechanics of Membranes

The fluctuations of two-dimensional extended objects membranes is a rich and exciting field with many solid results and a wide range of open issues. We review the distinct universality classes of membranes, determined by the local order, and the associated phase diagrams. After a discussion of several physical examples of membranes we turn to the physics of crystalline (or polymerized) membranes in which the individual monomers are rigidly bound. We discuss the phase diagram with particular attention to the dependence on the degree of self-avoidance and anisotropy. In each case we review and discuss analytic, numerical and experimental predictions of critical exponents and other key observables. Particular emphasis is given to the results obtained from the renormalization group epsilon-expansion. The resulting renormalization group flows and fixed points are illustrated graphically. The full technical details necessary to perform actual calculations are presented in the Appendices. We then turn to a discussion of the role of topological defects whose liberation leads to the hexatic and fluid universality classes. We finish with conclusions and a discussion of promising open directions for the future.Comment: 75 LaTeX pages, 36 figures. To appear in Physics Reports in the Proceedings of RG2000, Taxco, 199

Plasma Electronics

Contains reports on four research projects.United States ArmyUnited States NavyUnited States Air Force (Contract AF19(604)-7400)Lincoln Laboratory (Purchase Order DDL BB-107)National Science Foundation (Grant G-24073

Plasma Electronics

Contains reports on six research projects.United States Navy, Office of Naval Research (Contract Nonr-1841(78))Lincoln Laboratory (Purchase Order DDL B-00337)United States ArmyUnited States Air Force (Contract AF19(604)-7400)United States NavyNational Science Foundation (Grant G-9330