Health Insurance Literacy Improvements Among Recently Diagnosed Adolescents and Young Adults With Cancer: Results From a Pilot Randomized Controlled Trial.

PURPOSE: Adolescents and young adults (AYAs; age 18-39 years) with cancer report needing support with health insurance. We conducted a pilot randomized controlled trial to assess the feasibility and acceptability of a virtual health insurance navigation intervention (HIAYA CHAT) to improve health insurance literacy (HIL), awareness of Affordable Care Act (ACA) protections, financial toxicity, and stress. MATERIALS AND METHODS: HIAYA CHAT is a four-session navigator delivered program; it includes psychoeducation on insurance, navigating one's plan, insurance-related laws, and managing costs. Participants were eligible if they could access an internet-capable device, were <1 year from diagnosis, and received treatment from University of Utah Healthcare or Intermountain Health systems. We assessed the feasibility, acceptability, and preliminary efficacy of HIAYA CHAT compared with usual navigation care, including HIL (nine items), insurance knowledge (13 items), ACA protections (eight items), COmprehensive Score for financial Toxicity (COST; 11 items), and Perceived Stress Scale (PSS; four items), using t tests and Cohen's d. RESULTS: From November 2020 to December 2021, N = 86 AYAs enrolled (44.6% participation) and 89.3% completed the 5-month follow-up survey; 68.6% were female, 72.1% were White, 23.3% were Hispanic, 65.1% were age 26-39 years, and 87.2% were privately insured. Of intervention participants (n = 45), 67.4% completed all four sessions; among an exit interview subset (n = 10), all endorsed the program (100%). At follow-up, compared with usual navigation care, intervention participants had greater improvements in HIL, insurance and ACA protections knowledge, and PSS; effect sizes ranged from moderate to large (0.42-0.77). COST did not differ. CONCLUSION: The results support the feasibility and acceptability of HIAYA CHAT with related improvements in HIL.

Variation in Treatment Charges and Reimbursement Among Individual Thoracic Surgeons.

BACKGROUND: Health care use and costs have undergone an increase in public scrutiny. Other specialties have evaluated practice patterns of their most highly reimbursed surgeons and found unique billing and procedure overuse. In this study, we evaluate Medicare payments to general thoracic surgeons and evaluate those with the highest reimbursements. METHODS: The 2018 Medicare Provider Utilization Data were queried to identify thoracic surgeons. Services were grouped into common categories: Evaluation and Management, Lung/Pleura, Foregut, Chest Wall, Airway, Diaphragm, Mediastinum, Endoscopy, and Transplant. Payment data were analyzed for surgeons receiving the top 1% of Medicare payments and the remainder of the workforce. RESULTS: In 2018, 2000 unique self-identified thoracic surgeons received a total of $54,734,736 in payments from Medicare for thoracic-related services. The top 1% of thoracic surgeons (n = 20) received $4,607,561, or 8.4% of total payments. Inpatient Evaluation and Management was the leading payment category for the top 1% (48.5% of payments), whereas Outpatient Evaluation and Management led for the remaining workforce (43.5% of payments). Whereas the surgical procedure code with overall highest reimbursement for both groups was Current Procedural Terminology (American Medical Association) 32663 (video-assisted thoracic surgery lobectomy), there was a difference with an increased use of high relative value unit unbundled Current Procedural Terminology codes in the highest earners. CONCLUSIONS: A disproportionate amount of Medicare reimbursement went to top 1%. The highest earners appeared to earn the most from inpatient treatment codes and also used unbundled codes more often. Because billing code use is not regulated and often subjective, a deeper evaluation by the major surgical societies may be warranted.

Evaluation of novel candidate filtration markers from a global metabolomic discovery for glomerular filtration rate estimation.

Creatinine and cystatin-C are recommended for estimating glomerular filtration rate (eGFR) but accuracy is suboptimal. Here, using untargeted metabolomics data, we sought to identify candidate filtration markers for a new targeted assay using a novel approach based on their maximal joint association with measured GFR (mGFR) and with flexibility to consider their biological properties. We analyzed metabolites measured in seven diverse studies encompasing 2,851 participants on the Metabolon H4 platform that had Pearson correlations with log mGFR and used a stepwise approach to develop models to < -0.5 estimate mGFR with and without inclusion of creatinine that enabled selection of candidate markers. In total, 456 identified metabolites were present in all studies, and 36 had correlations with mGFR < -0.5. A total of 2,225 models were developed that included these metabolites; all with lower root mean square errors and smaller coefficients for demographic variables compared to estimates using untargeted creatinine. Seventeen metabolites were chosen, including 12 new candidate filtration markers. The selected metabolites had strong associations with mGFR and little dependence on demographic factors. Candidate metabolites were identified with maximal joint association with mGFR and minimal dependence on demographic variables across many varied clinical settings. These metabolites are excreted in urine and represent diverse metabolic pathways and tubular handling. Thus, our data can be used to select metabolites for a multi-analyte eGFR determination assay using mass spectrometry that potentially offers better accuracy and is less prone to non-GFR determinants than the current eGFR biomarkers.

Response to high dose ipilimumab plus temozolomide after progression on standard or low dose ipilimumab in advanced melanoma: a retrospective analysis.

Background: Despite advancements in checkpoint inhibitor-based immunotherapy, patients with advanced melanoma who have progressed on standard dose ipilimumab (Ipi) + nivolumab continue to have poor prognosis. Several studies support a dose-response activity of Ipi, and one promising combination is Ipi 10mg/kg (Ipi10) + temozolomide (TMZ). Methods: We performed a retrospective cohort analysis of patients with advanced melanoma treated with Ipi10+TMZ in the immunotherapy refractory/resistant setting (n = 6), using similar patients treated with Ipi3+TMZ (n = 6) as comparison. Molecular profiling by whole exome sequencing (WES) and RNA-seq of tumors harvested through one responder's treatment was performed. Results: With a median follow up of 119 days, patients treated with Ipi10+TMZ had statistically significant longer median progression free survival of 144.5 days (range 27-219) vs 44 (26-75) in Ipi3+TMZ, p=0.04, and a trend for longer median overall survival of 154.5 days (27-537) vs 89.5 (26-548). All patients in the Ipi10 cohort had progressed on prior Ipi+Nivo. WES revealed only 12 shared somatic mutations including BRAF V600E. RNA-seq showed enrichment of inflammatory signatures, including interferon responses in metastatic lesions after standard dose Ipi + nivo and Ipi10 + TMZ compared to the primary tumor, and downregulated negative immune regulators including Wnt and TGFb signaling. Conclusion: Ipi10+TMZ demonstrated efficacy including dramatic responses in patients with advanced melanoma refractory to prior Ipi + anti-PD1, even with CNS metastases. Molecular data suggest a potential threshold of Ipi dose for activation of sufficient anti-tumor immune response, and higher dose Ipi is required for some patients.

Adipose Tissue Distribution and Body Mass Index (BMI) Correlation With Daily Image-Guided Radiotherapy (IGRT) Shifts of Abdominal Radiation Therapy Patients.

Purpose There are several studies suggesting a correlation between image-guided radiotherapy (IGRT) setup errors and body mass index (BMI). However, abdominal fat content has visceral and subcutaneous components, which may affect setup errors differently. This study aims to analyze a potential workflow for characterizing adipose content and distribution in the region of the target that would allow a quickly calculated metric of abdominal fat content to stratify these patients. Methods IGRT shift data was retrospectively tabulated from daily fan-beam CT-on-rails pre-treatment alignment for 50 abdominal radiation therapy (RT) patients, and systematic and random errors in the daily setup were characterized by tabulating average and standard deviations of shift data for each patient and looking at differences for different distributions of adipose content. Visceral and subcutaneous fat content were defined by visceral fat area (VFA) and subcutaneous fat area (SFA) using a region-growing algorithm to contour adipose tissue on CT simulation scans. All contours were created for a single slice at the treatment isocenter, on which the VFA and SFA were calculated. A log-rank test was used to test trends in shifts over quartiles of adiposity. Results VFA ranged from 1.9-342.8c m2, and SFA from 11.8-756.0 cm2. The standard definition (SD) of random error (σ) in the lateral axis for Q1 vs. Q4 VFA was 0.10cm vs. 0.29cm, 0.12cm vs. 0.28cm for SFA, and 0.12cm vs. 0.31cm for BMI. The percentage of longitudinal shifts greater than 10mm for Q1 vs. Q4 VFA was 0% vs. 9%, 2% vs. 19% for SFA, and 0% vs. 20% for BMI. Statistically significant trends in shifts vs. the BMI quartile were seen for both pitch and the longitudinal direction, as well as for pitch corrections vs. the VFA quartile. Conclusion Within this dataset, abdominal cancer patients showed statistically significant trends in shift probability vs. BMI and VFA. Also, patients in the upper quartiles of all adiposity metrics showed an increased SD of σ in the lateral direction and increased shifts over 10 mm in the longitudinal direction. However, despite these relationships, neither VFA nor SFA offered discernible advantages in their relationship to shift uncertainty relative to BMI.

Variability in Excess Lobectomy Billing Among US Thoracic Surgeons.

BACKGROUND: Transparency in physician billing practices in the United States is lacking. Often, charges may vary substantially between providers and excess charges may be passed on to the patient. In this study, we evaluate Medicare charges and payments for minimally invasive lobectomy to obtain a sense of national billing practices and evaluate for predictors of higher charges. METHODS: The 2018 Medicare Provider Utilization Data was queried to identify surgeons submitting charges for Video-Assisted Thoracoscopic Lobectomy. Excess charges were determined by each provider. Additional demographic variables were collected including geographic region for general surgery and cardiothoracic surgery training, years in practice, and current practice setting. A multivariate gamma regression was utilized to determine predictors of high billing practices. RESULTS: A total of 307 unique providers submitted charges ranging from $1,104 to $25,128 with a median of $4,265. The average Medicare Payment amount ranged from $163 to $1,409, with a median of $1,056. Male surgeons were estimated to charge 1.3 times more than female surgeons, while those in an academic setting were estimated to charge 1.4 times more than private practice (p < 0.01). Surgeons practicing in the South or West were estimated to charge 0.76 and 0.81 times as much as those practicing in the Northeast (p < 0.01). CONCLUSIONS: Billing practices vary widely across the United States. Charges submitted to Medicare likely represent a provider's charges across all payers. In today's healthcare economy, it is important for patients to understand the true cost of care and for providers to be mindful of reasonable and appropriate charges.

Tailored visuals, implementation interventions, and sun safe behavior: A longitudinal message experiment.

OBJECTIVE: One way to communicate skin cancer risk is through ultraviolet (UV) photographs, which can depict the target person (tailored visual) or someone else (stock visual). There is a need for more longitudinal research examining the relative impact of tailored UV photographs compared with other message interventions that could increase sun safe behaviors. METHOD: Students 14-18 years of age (N = 654) at eleven high schools in Utah were recruited to participate in a longitudinal experiment (assessments: pretest, posttest, 1 month follow-up) comparing the relative persuasive impact of receiving either (a) stock and tailored UV photographs or (b) stock UV photographs and an implementation intervention on outdoor tanning behavior. Participants completed measures of fear, appearance norms and benefits, threat susceptibility/severity, self-efficacy, response efficacy, freedom threat, reactance, and outdoor tanning behavior. RESULTS: Compared with the implementation intervention, participants in the tailored UV condition reported increased fear and freedom threat and decreased appearance norms and benefits of tanning immediately following exposure to the intervention and decreased outdoor tanning 1 month after the intervention. Indirect effects also emerged with tailored UV exposure decreasing outdoor tanning via appearance benefits and increasing outdoor tanning when immediate fear triggered psychological reactance. CONCLUSIONS: The results contribute to research on lay reactions to tailored visuals, implementation interventions, and theorizing the indirect effects of affect and cognition across time. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Improving Antibiotic Stewardship for Diarrheal Disease With Probability-Based Electronic Clinical Decision Support: A Randomized Crossover Trial.

Importance: Inappropriate use of antibiotics for diarrheal illness can result in adverse effects and increase in antimicrobial resistance. Objective: To determine whether the diarrheal etiology prediction (DEP) algorithm, which uses patient-specific and location-specific features to estimate the probability that diarrhea etiology is exclusively viral, impacts antibiotic prescriptions in patients with acute diarrhea. Design, Setting, and Participants: A randomized crossover study was conducted to evaluate the DEP incorporated into a smartphone-based electronic clinical decision-support (eCDS) tool. The DEP calculated the probability of viral etiology of diarrhea, based on dynamic patient-specific and location-specific features. Physicians were randomized in the first 4-week study period to the intervention arm (eCDS with the DEP) or control arm (eCDS without the DEP), followed by a 1-week washout period before a subsequent 4-week crossover period. The study was conducted at 3 sites in Bangladesh from November 17, 2021, to January 21, 2021, and at 4 sites in Mali from January 6, 2021, to March 5, 2021. Eligible physicians were those who treated children with diarrhea. Eligible patients were children between ages 2 and 59 months with acute diarrhea and household access to a cell phone for follow-up. Interventions: Use of the eCDS with the DEP (intervention arm) vs use of the eCDS without the DEP (control arm). Main Outcomes and Measures: The primary outcome was the proportion of children prescribed an antibiotic. Results: A total of 30 physician participants and 941 patient participants (57.1% male; median [IQR] age, 12 [8-18] months) were enrolled. There was no evidence of a difference in the proportion of children prescribed antibiotics by physicians using the DEP (risk difference [RD], -4.2%; 95% CI, -10.7% to 1.0%). In a post hoc analysis that accounted for the predicted probability of a viral-only etiology, there was a statistically significant difference in risk of antibiotic prescription between the DEP and control arms (RD, -0.056; 95% CI, -0.128 to -0.01). No known adverse effects of the DEP were detected at 10-day postdischarge. Conclusions and Relevance: Use of a tool that provides an estimate of etiological likelihood did not result in a significant change in overall antibiotic prescriptions. Post hoc analysis suggests that a higher predicted probability of viral etiology was linked to reductions in antibiotic use. Trial Registration: Clinicaltrials.gov Identifier: NCT04602676.

HIAYA CHAT study protocol: a randomized controlled trial of a health insurance education intervention for newly diagnosed adolescent and young adult cancer patients.

BACKGROUND: For adolescent and young adult (AYA) cancer patients aged 18 to 39 years, health insurance literacy is crucial for an effective use of the health care system. AYAs often face high out-of-pocket costs or have unmet health care needs due to costs. Improving health insurance literacy could help AYAs obtain appropriate and affordable health care. This protocol illustrates a randomized controlled trial testing a virtual health insurance education intervention among AYA patients. METHODS: This is a two-arm multisite randomized controlled trial. A total of 80 AYAs diagnosed with cancer in the Mountain West region will be allocated to either usual navigation care or tailored health insurance education intervention with a patient navigator that includes usual care. All participants will complete a baseline and follow-up survey 5 months apart. The primary outcomes are feasibility (number enrolled and number of sessions completed) and acceptability (5-point scale on survey measuring satisfaction of the intervention). The secondary outcomes are preliminary efficacy measured by the Health Insurance Literacy Measure and the COmprehensive Score for financial Toxicity. DISCUSSION: This trial makes a timely contribution to test the feasibility and acceptability of a virtual AYA-centered health insurance education program. TRIAL REGISTRATION: ClinicalTrials.gov NCT04448678. Registered on June 26, 2020.

Mental health disorders are more common in patients with Hodgkin lymphoma and may negatively impact overall survival.

BACKGROUND: Long-term mental health outcomes were characterized in patients who were diagnosed with Hodgkin lymphoma (HL), and risk factors for the development of mental health disorders were identified. METHODS: Patients who were diagnosed with HL between 1997 and 2014 were identified in the Utah Cancer Registry. Each patient was matched with up to five individuals from a general population cohort identified within the Utah Population Database, a unique source of linked records that includes patient and demographic data. RESULTS: In total, 795 patients who had HL were matched with 3575 individuals from the general population. Compared with the general population, patients who had HL had a higher risk of any mental health diagnosis (hazard ratio, 1.77; 95% confidence interval, 1.57-2.00). Patients with HL had higher risks of anxiety, depression, substance-related disorders, and suicide and intentional self-inflicted injuries compared with the general population. The main risk factor associated with an increased risk of being diagnosed with mental health disorders was undergoing hematopoietic stem cell transplantation, with a hazard ratio of 2.06 (95% confidence interval, 1.53-2.76). The diagnosis of any mental health disorder among patients with HL was associated with a detrimental impact on overall survival; the 10-year overall survival rate was 70% in patients who had a mental health diagnosis compared with 86% in those patients without a mental health diagnosis (p < .0001). CONCLUSIONS: Patients who had HL had an increased risk of various mental health disorders compared with a matched general population. The current data illustrate the importance of attention to mental health in HL survivorship, particularly for patients who undergo therapy with hematopoietic stem cell transplantation.

Trends and factors affecting approach choice to pulmonary resection.

BACKGROUND: The development of an advanced robotic platform in 2014 led to increased adoption of minimally invasive (MI) approaches in thoracic surgery. Due to dataset reporting lag, a comprehensive assessment of trends in thoracic approaches has not been analyzed to date. METHODS: We queried the National Cancer Database (NCDB) for patients with Stage I-III who underwent lung resection from 2010 to 2018. Most published NCDB analyses on lung cancer using pre-2015 data. Overall treatment trends were analyzed, with geographic, institutional, and socioeconomic characteristics evaluated for approach. RESULTS: There were 162 335 lung resections, and 131 958 were anatomic. Robotic resection saw a steady increase through 2012 but plateaued in 2013-2014. From 2015 to 2018, another increase correlated with the release of a new platform. Video-assisted thoracoscopic surgery lung resection plateaued in 2014 and decreased in 2018. Open resection steadily decreased. Tumors requiring neoadjuvant radiation had an increase in MI approach with corresponding decreases in the open. On multivariable analysis, African-American race, low volume, Medicaid insurance, and nonacademic setting were associated with a lower likelihood of MI surgery. CONCLUSIONS: The open approach has decreased since 2010. More than 65% of anatomic resections are now performed in MI. As this trend will continue, it is important that all patients are afforded the opportunity of the least invasive approach.

Histologic Growth Patterns in Clear Cell Renal Cell Carcinoma Stratify Patients into Survival Risk Groups.

INTRODUCTION: Genomic and morphologic heterogeneity in clear cell renal cell carcinoma (ccRCC) presents a barrier to prognostication and treatment decisions. Data from pathology are used with clinical markers to predict disease progression after nephrectomy. However, determining the risk of cancer recurrence, and survival with metastatic cancer remains challenging. Recently, analysis of histologic growth patterns (HGP) in ccRCC revealed promising associations with survival outcomes. METHODS: To investigate whether HGPs can be used to predict overall survival (OS) after nephrectomy, we examined 24 HGPs in primary tumors of 147 patients that included 107 patients with metastatic disease. RESULTS: The median number of HGPs per case was 5 and was greater in metastatic and larger tumors. After adjustment for 6 pathologic and demographic variables, HGPs were significantly associated with OS post nephrectomy. Small nests, expansile nests and nests with high nuclear to cytoplasmic ratio were associated with favorable outcomes; while spindled low grade, fused nests/solid sheets, rhabdoid, and sarcomatoid patterns were associated with unfavorable outcomes. A 3-tiered and a 2-tiered risk model were developed based on combinations of HGPs. The models performed equally well as WHO/ISUP nucleolar plus necrosis grade (necrosis grade), and better than WHO/ISUP nucleolar grade alone in predicting OS at the median OS of 6 years. Pairwise correlations between HGPs revealed 2 tumor evolutionary branches that differed in risk of metastatic disease: one with mesenchymal differentiation, and other with epithelial tubulopapillary differentiation. While 44 of 107 (41%) patients with metastatic ccRCC displayed evidence of mesenchymal differentiation, mesenchymal features were only observed in 1 of 40 (3%) patients without evidence of metastatic disease. CONCLUSION: These findings suggest that HGPs may provide a novel path to refine the estimation of OS after nephrectomy and to determine the molecular basis of tumor evolution.

A Veterans' Healthcare Administration (VHA) antibiotic stewardship intervention to improve outpatient antibiotic use for acute respiratory infections: A cost-effectiveness analysis.

OBJECTIVES: The Core Elements of Outpatient Antibiotic Stewardship provides a framework to improve antibiotic use, but cost-effectiveness data on implementation of outpatient antibiotic stewardship interventions are limited. We evaluated the cost-effectiveness of Core Element implementation in the outpatient setting. METHODS: An economic simulation model from the health-system perspective was developed for patients presenting to outpatient settings with uncomplicated acute respiratory tract infections (ARI). Effectiveness was measured as quality-adjusted life years (QALYs). Cost and utility parameters for antibiotic treatment, adverse drug events (ADEs), and healthcare utilization were obtained from the literature. Probabilities for antibiotic treatment and appropriateness, ADEs, hospitalization, and return ARI visits were estimated from 16,712 and 51,275 patient visits in intervention and control sites during the pre- and post-implementation periods, respectively. Data for materials and labor to perform the stewardship activities were used to estimate intervention cost. We performed a one-way and probabilistic sensitivity analysis (PSA) using 1,000,000 second-order Monte Carlo simulations on input parameters. RESULTS: The proportion of ARI patient-visits with antibiotics prescribed in intervention sites was lower (62% vs 74%) and appropriate treatment higher (51% vs 41%) after implementation, compared to control sites. The estimated intervention cost over a 2-year period was $133,604 (2018 US dollars). The intervention had lower mean costs ($528 vs $565) and similar mean QALYs (0.869 vs 0.868) per patient compared to usual care. In the PSA, the intervention was dominant in 63% of iterations. CONCLUSIONS: Implementation of the CDC Core Elements in the outpatient setting was a cost-effective strategy.

Colchicine effectiveness in symptom and inflammation modification in knee osteoarthritis (COLKOA): study protocol for a randomized controlled trial.

BACKGROUND: Despite the high prevalence and global impact of knee osteoarthritis (KOA), current treatments are palliative. No disease modifying anti-osteoarthritic drug (DMOAD) has been approved. We recently demonstrated significant involvement of uric acid and activation of the innate immune response in osteoarthritis (OA) pathology and progression, suggesting that traditional gout therapy may be beneficial for OA. We therefore assess colchicine, an existing commercially available agent for gout, for a new therapeutic application in KOA. METHODS/DESIGN: COLKOA is a double-blind, placebo-controlled, randomized trial comparing a 16-week treatment with standard daily dose oral colchicine to placebo for KOA. A total of 120 participants with symptomatic KOA will be recruited from a single center in Singapore. The primary end point is 30% improvement in total Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score at week 16. Secondary end points include improvement in pain, physical function, and quality of life and change in serum, urine and synovial fluid biomarkers of cartilage metabolism and inflammation. A magnetic resonance imaging (MRI) substudy will be conducted in 20 participants to evaluate change in synovitis. Logistic regression will be used to compare changes between groups in an intention-to-treat analysis. DISCUSSION: The COLKOA trial is designed to evaluate whether commercially available colchicine is effective for improving signs and symptoms of KOA, and reducing synovial fluid, serum and urine inflammatory and biochemical joint degradation biomarkers. These biomarkers should provide insights into the underlying mechanism of therapeutic response. This trial will potentially provide data to support a new treatment option for KOA. TRIAL REGISTRATION: The trial has been registered at clinicaltrials.gov as NCT02176460 . Date of registration: 26 June 2014.

Bayesian semiparametric predictive modeling with applications in dose-response prediction.

A framework is proposed for making quality predictions in situations for which only systematically inaccurate data are available. The predictions are based on the systematically inaccurate data, complete data from similar situations, and expert knowledge. The proposed predictive model is well suited to functional data and is computationally simple, fast, and stable. We focus primarily on a particular problem presenting itself in the pharmaceutical industry. Predicting both side effect and endpoint dose responses before the initiation of a clinical trial has enormous ethical and financial importance in the pharmaceutical industry. The proposed Bayesian semiparametric predictive model is used to predict unobserved clinical dose-response curves conditional on preclinical data, data from similar compounds, and prior knowledge. The model allows for nonlinear dose-response curves and the incorporation of relevant prior information. Posterior sampling is achieved through a simple and computationally efficient Gibbs sampler. The predictions from the model are drawn from the posterior distribution of the average dose-response curve for the candidate compound, allowing straightforward incorporation into a risk assessment model unlike the deterministic predictions often used currently. The model is used on actual data from the pharmaceutical industry, showing that the model is capable of predicting lack or presence of trend with appropriate uncertainty.

An Approach to Constructing Nested Space-Filling Designs for Multi-Fidelity Computer Experiments.

Multi-fidelity computer experiments are widely used in many engineering and scientific fields. Nested space-filling designs (NSFDs) are suitable for conducting such experiments. Two classes of NSFDs are currently available. One class is based on special orthogonal arrays of strength two and the other consists of nested Latin hypercube designs. Both of them assume all factors are continuous. We propose an approach to constructing new NSFDs based on powerful (t, s)-sequences. The method is simple, easy to implement, and quite general. For continuous factors, this approach produces NSFDs with better space-filling properties than existing ones. Unlike the previous methods, this method can also construct NSFDs for categorical and mixed factors. Some illustrative examples are given. Other applications of the constructed designs are briefly discussed.

A Statistical Approach to Thermal Management of Data Centers Under Steady State and System Perturbations.

Temperature control for a large data center is both important and expensive. On the one hand, many of the components produce a great deal of heat, and on the other hand, many of the components require temperatures below a fairly low threshold for reliable operation. A statistical framework is proposed within which the behavior of a large cooling system can be modeled and forecast under both steady state and perturbations. This framework is based upon an extension of multivariate Gaussian autoregressive hidden Markov models (HMMs). The estimated parameters of the fitted model provide useful summaries of the overall behavior of and relationships within the cooling system. Predictions under system perturbations are useful for assessing potential changes and improvements to be made to the system. Many data centers have far more cooling capacity than necessary under sensible circumstances, thus resulting in energy inefficiencies. Using this model, predictions for system behavior after a particular component of the cooling system is shut down or reduced in cooling power can be generated. Steady-state predictions are also useful for facility monitors. System traces outside control boundaries flag a change in behavior to examine. The proposed model is fit to data from a group of air conditioners within an enterprise data center from the IT industry. The fitted model is examined, and a particular unit is found to be underutilized. Predictions generated for the system under the removal of that unit appear very reasonable. Steady-state system behavior also is predicted well.

Correlation of MRI findings with clinical findings of trochanteric pain syndrome.

OBJECTIVE: Greater trochanter pain syndrome due to tendinopathy or bursitis is a common cause of hip pain. The previously reported magnetic resonance (MR) findings of trochanteric tendinopathy and bursitis are peritrochanteric fluid and abductor tendon abnormality. We have often noted peritrochanteric high T2 signal in patients without trochanteric symptoms. The purpose of this study was to determine whether the MR findings of peritrochanteric fluid or hip abductor tendon pathology correlate with trochanteric pain. MATERIALS AND METHODS: We retrospectively reviewed 131 consecutive MR examinations of the pelvis (256 hips) for T2 peritrochanteric signal and abductor tendon abnormalities without knowledge of the clinical symptoms. Any T2 peritrochanteric abnormality was characterized by size as tiny, small, medium, or large; by morphology as feathery, crescentic, or round; and by location as bursal or intratendinous. The clinical symptoms of hip pain and trochanteric pain were compared to the MR findings on coronal, sagittal, and axial T2 sequences using chi-square or Fisher's exact test with significance assigned as p < 0.05. RESULTS: Clinical symptoms of trochanteric pain syndrome were present in only 16 of the 256 hips. All 16 hips with trochanteric pain and 212 (88%) of 240 without trochanteric pain had peritrochanteric abnormalities (p = 0.15). Eighty-eight percent of hips with trochanteric symptoms had gluteus tendinopathy while 50% of those without symptoms had such findings (p = 0.004). Other than tendinopathy, there was no statistically significant difference between hips with or without trochanteric symptoms and the presence of peritrochanteric T2 abnormality, its size or shape, and the presence of gluteus medius or minimus partial thickness tears. CONCLUSIONS: Patients with trochanteric pain syndrome always have peritrochanteric T2 abnormalities and are significantly more likely to have abductor tendinopathy on magnetic resonance imaging (MRI). However, although the absence of peritrochanteric T2 MR abnormalities makes trochanteric pain syndrome unlikely, detection of these abnormalities on MRI is a poor predictor of trochanteric pain syndrome as these findings are present in a high percentage of patients without trochanteric pain.