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The effectiveness of bone density testing for identifying risks of fracture due to osteoporosis in women in different age groups is discussed.

Objective. To develop and validate a clinically informed algorithm that uses solely Medicare claims to identify, with a high positive predictive value, incident breast cancer cases. Data Source. Population-based Surveillance, Epidemiology, and End Results (SEER) Tumor Registry data linked to Medicare claims, and Medicare claims from a 5 percent random sample of beneficiaries in SEER areas. Study Design. An algorithm was developed using claims from 1995 breast cancer patients from the SEER-Medicare database, as well as 1995 claims from Medicare control subjects. The algorithm was validated on claims from breast cancer subjects and controls from 1994. The algorithm development process used both clinical insight and logistic regression methods. Data Extraction. Training set: Claims from 7,700 SEER-Medicare breast cancer subjects diagnosed in 1995, and 124,884 controls. Validation set: Claims from 7,607 SEER-Medicare breast cancer subjects diagnosed in 1994, and 120,317 controls. Principal Findings. A four-step prediction algorithm was developed and validated. It has a positive predictive value of 89 to 93 percent, and a sensitivity of 80 percent for identifying incident breast cancer. The sensitivity is 82-87 percent for stage I or II, and lower for other stages. The sensitivity is 82-83 percent for women who underwent either breast-conserving surgery or mastectomy, and is similar across geographic sites. A cohort identified with this algorithm will have 89-93 percent incident breast cancer cases, 1.5-6 percent cancer free cases, and 4-5 percent prevalent breast cancer cases. Conclusions. This algorithm has better performance characteristics than previously proposed algorithms. The ability to examine national patterns of breast cancer care using Medicare claims data would open new avenues for the assessment of quality of care. Key Words. Breast neoplasm, incidence, sensitivity and specificity, registries, Medicare, The quality of cancer care in the United States is known to be variable, and factors determining quality of cancer care have been insufficiently studied (Hewitt and Simone 1999). The [...]

This article analyzes the effectiveness of cost-effectiveness analysis by employing the Bayesian technique and comparing the results with univariate sensitivity analyses in determining uncertainties. The authors, employing the methods to several HIV intervention programs, conclude both methods were comparable.

ABSTRACTHousing discrimination and racial segregation have a long history in the United States. The 1930s Home Owners’ Loan Corporation (HOLC) “residential security maps,” recently digitized, have become a popular visualization of Depression era mortgage lending risk patterns across American cities. Numerous housing policies have since been instituted, including the Home Mortgage Disclosure Act (HMDA), but mortgage lending bias persists. The degree to which detailed spatial patterns of bias have persisted or changed along with urban change is not well understood. We compare historic HOLC grades and contemporary levels of mortgage lending bias using spatially detailed HMDA data. We further examine the relationship between HOLC risk grades and contemporary racial and ethnic settlement patterns. Results suggest that historical mortgage lending risk categorizations and settlement patterns are associated with contemporary mortgage lending bias and racial and ethnic settlement patterns. Concerted and deliberate efforts will be needed to change these patterns.

Yearly influenza vaccination is strongly recommended at age 65 and reimbursed by Medicare without copays or deductibles at pharmacies and clinical settings. Uptake is low among patients with a high risk for influenza complications and good access to specialist care, such as recent cancer survivors. We hypothesized that more accessible pharmacies could be associated with higher immunization uptake in such patients.

To authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1532-5415.2009.02714.x Byline: Tina W. F. Yen (*), Rodney A. Sparapani ([dagger]), Changbin Guo ([dagger]), Joan M. Neuner ([double dagger]), Purushottam W. Laud ([dagger]), Ann B. Nattinger ([double dagger]) Author Affiliation: (*)Division of General Surgery ([dagger])Division of Biostatistics ([double dagger])Department of Medicine, Center for Patient Care and Outcomes Research, Medical College of Wisconsin, Milwaukee, Wisconsin

Purpose: Virtual surgery planning based on computational fluid dynamics (CFD) simulations of nasal airflow has the potential to improve surgical outcomes for patients with nasal airway obstruction (NAO). Virtual surgery planning requires normative ranges of airflow variables, but few studies to date have quantified inter-individual variability of nasal airflow among healthy subjects. This study reports CFD simulations of nasal airflow in 47 healthy adults. Methods: Anatomically accurate three-dimensional nasal models were reconstructed from cone beam computed tomography scans and used for steady-state inspiratory airflow simulations with a bilateral flowrate of 250 ml/s. Normal subjective sensation of nasal patency was confirmed using the nasal obstruction symptom evaluation and visual analog scale. Healthy ranges for several CFD variables known to correlate with subjective nasal patency were computed, including unilateral airflow, nasal resistance, airspace minimal cross-sectional area (mCSA), heat flux (HF), and surface area stimulated by mucosal cooling (defined as the area where HF > 50 W/m2). The normative ranges were targeted to contain 95% of the healthy population and computed using a nonparametric method based on order statistics. Results: A wide range of inter-individual variability in nasal airflow was observed among healthy subjects. Unilateral airflow varied from 60 to 191 ml/s, airflow partitioning ranged from 23.8 to 76.2%, and unilateral mCSA varied from 0.24 to 1.21 cm2. These ranges are in good agreement with rhinomanometry and acoustic rhinometry data from the literature. A key innovation of this study are the normative ranges of flow variables associated with mucosal cooling, which recent research suggests is the primary physiological mechanism of nasal airflow sensation. Unilateral HF ranged from 94 to 281 W/m2, while the surface area stimulated by cooling ranged from 27.4 to 64.3 cm2. Conclusions: These normative ranges may serve as targets in future virtual surgery planning for patients with NAO.

•Donors aged 18 to 30 years yield equivalent OS after matched unrelated donor transplantation based on a novel machine learning approach.•Male donors are associated with improved EFS, but donor sex does not associate with improved OS.

INTRODUCTIONOur recently published research has shown younger donors have superior survival for recipients of allogeneic hematopoietic stem cell transplant (HSCT). But, previously, we had not explored the donor age impact on other outcomes, or the impact of smaller age differences (<4 years) when balanced against other factors. We report results using our recently developed machine learning survival methodology, Nonparametric Failure Time Bayesian Additive Regression Trees (NFT BART). Here we study patient-specific optimization of donor selection for overall survival (OS) and event-free survival (EFS including events of death, relapse, graft failure/rejection, or moderate/severe chronic graft vs. host disease, GVHD).

Supplemental Digital Content is available in the text.

Supplemental Digital Content is available in the text.

ABSTRACTBackground Continuity for inpatient medicine has been widely discussed, but methods for measuring it have been lacking.Objective To measure the continuity of care experienced by hospitalized patients and to identify predictors of continuity.Methods This was a multisite prospective cohort study and retrospective chart review that took place at 3 hospitals: an academic tertiary care center, a Veterans Affairs medical center, and a community teaching hospital. Subjects were general medicine patients and internal medicine residents. We measured continuity of care using 3 metrics: (1) the percentage of hospital time covered by the primary intern; (2) the amount of time between admission and the first handoff of care; and (3) admission-discharge continuity. We conducted univariate analyses to identify patient and hospital factors that may be associated with each type of continuity of care.Results Our sample included 869 patients with a mean age of 62.6 years (SD 17.2) and 34 female patients. The mean percentage of hospital time covered by the primary intern was 39.2 (SD 16.3). The mean time between admission and the first handoff of care was 13.3 hours (SD 7.1). Forty percent of patients experienced admission-discharge continuity. In univariate and multivariable modeling, the site was significantly associated with each type of continuity.Conclusions The amount of continuity varied greatly and was influenced by the site and other factors. No site maximized every aspect of continuity. Programs and institutions should decide which aspects of continuity are most important locally and design schedules accordingly.

Adjuvant endocrine therapy (AET) for breast cancer reduces mortality, but one-third to one-half of patients discontinue it early or are nonadherent.

HYPOTHESIS Adherence to National Institutes of Health consensus statement recommendations for early-stage breast cancer will vary by surgeon characteristics. DESIGN Secondary data analysis using the Surveillance, Epidemiology, and End Results national tumor registry linked with Medicare claims data. Logistic regression was used to analyze data on a cohort of 1045 surgeons who operated on 9449 Medicare patients with early-stage breast cancer. MAIN OUTCOME MEASURE Care adherent to the 1990 National Institutes of Health consensus statement recommendations. RESULTS Surgeon age and specialty were not associated with adherent care overall, nor among breast-conserving surgery or mastectomy subgroups. Patients of higher-volume surgeons were significantly more likely to undergo adherent care overall because of greater use of lymph node dissection among women who received either breast-conserving surgery or mastectomy. Patients of female surgeons and surgeons with a medical school affiliation were less likely to undergo adherent care overall, which was related to greater use of breast-conserving surgery and lesser use of lymph node dissection among patients who underwent breast-conserving surgery. CONCLUSIONS Several surgeon characteristics are significantly associated with variations in breast cancer treatment received. These results warrant further investigation into the association between these surgeon characteristics and cancer care outcomes.Arch Surg. 2007;142:17-22--

Purpose:Sex has been demonstrated to affect outcome in many diseases. Our current aim is to investigate the relationship between sex and outcomes of endoscopic sinus surgery (ESS) in patients with chronic rhinosinusitis (CRS).

Purpose:To assess objective and quality of life (QOL) outcomes before and after endoscopic sinus surgery (ESS) in patients with chronic rhinosinusitis (CRS) and to determine preoperative factors that predict surgical outcome in these patients.

Within the context of non-parametric Bayesian inference, Dykstra and Laud (1981) define an extended gamma (EG) process and use it as a prior on increasing hazard rates. The attractive features of the extended gamma (EG) process, among them its capability to index distribution functions that are absolutely continuous, are offset by the intractable nature of the computation that needs to be performed. Sampling based approaches such as the Gibbs Sampler can alleviate these difficulties but the EG processes then give rise to the problem of efficient random variate generation from a class of distributions called D-distributions. In this paper, we describe a novel technique for sampling from such distributions, thereby providing an efficient computation procedure for non-parametric Bayesian inference with a rich class of priors for hazard rates.

Recently, simulated annealing methods have proven to be a valuable tool for global optimization. We propose a new stochastic method for locating the global optimum of a function. The proposed method begins with the subjective specification of a probing distribution. The objective function is evaluated at a few points sampled from this distribution, which is then updated using the collected information. The updating mechanism is based on the entropy of a move selecting distribution and is loosely connected to some notions in statistical thermodynamics. Examples of the use of the proposed method are presented. These indicate its superior performance as compared with simulated annealing. Preliminary considerations in applying the method to discrete problems are discussed.

This article develops a distribution-free method for testing the independence of two random variables, each of which is continuous except at one discrete point, Two possible generalizations are also discussed briefly.

Purpose:As HCT recipients are at risk for late effects, SCPs are increasingly being used in clinical practice to facilitate survivor care despite the lack of high-quality data on their implementation or efficacy. We conducted a randomized study to evaluate the impact of SCPs on HCT survivors' confidence in survivorship information (CSI), with secondary analyses evaluating cancer treatment distress (CTXD), knowledge of transplant exposures, health behaviors, health care utilization (HCU) and health general self-efficacy.

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We present a goodness-of-fit test for multidimensional distributions which is a natural extension of the classical one-dimensional Kolmogorov test. The test is distribution free and the null distribution of the test statistic is the same as the univariate Kolmogorov test statistic in all higher dimensions.