Navigating global health diplomacy: challenges and opportunities in building a community of practice.

Addressing global health challenges requires complex coordination and collaboration between actors, often through the process of Global Health Diplomacy (GHD). Although considerable scholarship argues the importance of improving this process to build better health policies and systems, few studies have investigated the 'health diplomats' directly leading this work. In this study, we seek to better understand GHD from a practitioners' view by exploring perceptions of knowledge acquisition, capacity building, and network development amongst those who coordinate and orchestrate global policy solutions.

Optimal refinement of strata to balance covariates.

What is the best way to split one stratum into two to maximally reduce the within-stratum imbalance in many covariates? We formulate this as an integer program and approximate the solution by randomized rounding of a linear program. A linear program may assign a fraction of a person to each refined stratum. Randomized rounding views fractional people as probabilities, assigning intact people to strata using biased coins.

Exposure to Operative Anesthesia in Childhood and Subsequent Neurobehavioral Diagnoses: A Natural Experiment Using Appendectomy.

Background: Observational studies of anesthetic neurotoxicity may be biased because children requiring anesthesia commonly have medical conditions associated with neurobehavioral problems. This study takes advantage of a natural experiment associated with appendicitis to determine whether anesthesia and surgery in childhood were specifically associated with subsequent neurobehavioral outcomes.

Methods: This study identified 134,388 healthy children with appendectomy and examined the incidence of subsequent externalizing or behavioral disorders (conduct, impulse control, oppositional defiant, attention-deficit hyperactivity disorder) or internalizing or mood or anxiety disorders (depression, anxiety, or bipolar disorder) when compared to 671,940 matched healthy controls as identified in Medicaid data between 2001 and 2018.

Impact of Hospital Affiliation With a Flagship Hospital System on Surgical Outcomes.

Objective: To compare general surgery outcomes at flagship systems, flagship hospitals, and flagship hospital affiliates versus matched controls.

Summary Background Data: It is unknown whether flagship hospitals perform better than flagship hospital affiliates for surgical patients.

Methods: Using Medicare claims for 2018 to 2019, we matched patients undergoing inpatient general surgery in flagship system hospitals to controls who underwent the same procedure at hospitals outside the system but within the same region.

Hidden imaging in thin polymer films with embedded fluorescent peptide nanodots.

Fluorescent (FL) encrypting nanostructures, such as quantum dots, carbon dots, organic dyes, lanthanide nanocrystals, DNA, and more, are effective tools for advanced applications in high-resolution hidden imaging. These applications include tracking, labeling, security printing, and anti-counterfeiting drug technology. In this work, what we believe to be a new FL encoding nanostructures has been proposed, which consists of recently discovered nanometer-scale peptide dots.

Assessing the Ambulatory Surgery Center Volume-Outcome Association.

Importance: In surgical patients, it is well known that higher hospital procedure volume is associated with better outcomes. To our knowledge, this volume-outcome association has not been studied in ambulatory surgery centers (ASCs) in the US.

Objective: To determine if low-volume ASCs have a higher rate of revisits after surgery, particularly among patients with multimorbidity.

Mortality Among Older Medical Patients at Flagship Hospitals and Their Affiliates.

Background: We define a "flagship hospital" as the largest academic hospital within a hospital referral region and a "flagship system" as a system that contains a flagship hospital and its affiliates. It is not known if patients admitted to an affiliate hospital, and not to its main flagship hospital, have better outcomes than those admitted to a hospital outside the flagship system but within the same hospital referral region.

Objective: To compare mortality at flagship hospitals and their affiliates to matched control patients not in the flagship system but within the same hospital referral region.

A second evidence factor for a second control group.

In an observational study of the effects caused by a treatment, a second control group is used in an effort to detect bias from unmeasured covariates, and the investigator is content if no evidence of bias is found. This strategy is not entirely satisfactory: two control groups may differ significantly, yet the difference may be too small to invalidate inferences about the treatment, or the control groups may not differ yet nonetheless fail to provide a tangible strengthening of the evidence of a treatment effect. Is a firmer conclusion possible? Is there a way to analyze a second control group such that the data might report measurably strengthened evidence of cause and effect, that is, insensitivity to larger unmeasured biases? Evidence factor analyses are not commonly used with a second control group: most analyses compare the treated group to each control group, but analyses of that kind are partially redundant; so, they do not constitute evidence factors.

Explaining racial disparities in surgical survival: a tapered match analysis of patient and hospital factors.

Objectives: Evaluate whether hospital factors, including nurse resources, explain racial differences in Medicare black and white patient surgical outcomes and whether disparities changed over time.

Design: Retrospective tapered-match.

Setting: 571 hospitals at two time points (Early Era 2003-2005; Recent Era 2013-2015).

The Safety of Performing Surgery at Ambulatory Surgery Centers Versus Hospital Outpatient Departments in Older Patients With or Without Multimorbidity.

Background: Surgery for older Americans is increasingly being performed at ambulatory surgery centers (ASCs) rather than hospital outpatient departments (HOPDs), while rates of multimorbidity have increased.

Objective: To determine whether there are differential outcomes in older patients undergoing surgical procedures at ASCs versus HOPDs.

Research Design: Matched cohort study.

Redefining Multimorbidity in Older Surgical Patients.

Background: Multimorbidity in surgery is common and associated with worse postoperative outcomes. However, conventional multimorbidity definitions (≥2 comorbidities) label the vast majority of older patients as multimorbid, limiting clinical usefulness. We sought to develop and validate better surgical specialty-specific multimorbidity definitions based on distinct comorbidity combinations.

Defining Multimorbidity in Older Patients Hospitalized with Medical Conditions.

Background: The term "multimorbidity" identifies high-risk, complex patients and is conventionally defined as ≥2 comorbidities. However, this labels almost all older patients as multimorbid, making this definition less useful for physicians, hospitals, and policymakers.

Objective: Develop new medical condition-specific multimorbidity definitions for patients admitted with acute myocardial infarction (AMI), heart failure (HF), and pneumonia patients.

A statistic with demonstrated insensitivity to unmeasured bias for 2 × 2 × S tables in observational studies.

Are weak associations between a treatment and a binary outcome always sensitive to small unmeasured biases in observational studies? This possibility is often discussed in epidemiology. The familiar Mantel-Haenszel test for a contingency table exaggerates sensitivity to unmeasured biases when the population odds ratios vary among the strata. A statistic built from several components, here from the  strata, is said to have demonstrated insensitivity to bias if it uses only those components that provide indications of insensitivity to bias.

Sensitivity analyses informed by tests for bias in observational studies.

In an observational study, the treatment received and the outcome exhibited may be associated in the absence of an effect caused by the treatment, even after controlling for observed covariates. Two tactics are common: (i) a test for unmeasured bias may be obtained using a secondary outcome for which the effect is known and (ii) a sensitivity analysis may explore the magnitude of unmeasured bias that would need to be present to explain the observed association as something other than an effect caused by the treatment. Can such a test for unmeasured bias inform the sensitivity analysis? If the test for bias does not discover evidence of unmeasured bias, then ask: Are conclusions therefore insensitive to larger unmeasured biases? Conversely, if the test for bias does find evidence of bias, then ask: What does that imply about sensitivity to biases? This problem is formulated in a new way as a convex quadratically constrained quadratic program and solved on a large scale using interior point methods by a modern solver.

Alzheimer's Dementia After Exposure to Anesthesia and Surgery in the Elderly: A Matched Natural Experiment Using Appendicitis.

Objective: The aim of this study was to determine whether surgery and anesthesia in the elderly may promote Alzheimer disease and related dementias (ADRD).

Background: There is a substantial conflicting literature concerning the hypothesis that surgery and anesthesia promotes ADRD. Much of the literature is confounded by indications for surgery or has small sample size.

Using Medicare claims in identifying Alzheimer's disease and related dementias.

Introduction: This study develops a measure of Alzheimer's disease and related dementias (ADRD) using Medicare claims.

Methods: Validation resembles the approach of the American Psychological Association, including (1) content validity, (2) construct validity, and (3) predictive validity.

Results: We found that four items-a Medicare claim recording ADRD 1 year ago, 2 years ago, 3 years ago, and a total stay of 6 months in a nursing home-exhibit a pattern of association consistent with a single underlying ADRD construct, and presence of any two of these four items predict a direct measure of cognitive function and also future claims for ADRD.

Evaluating the Costs and Outcomes of Hospital Nursing Resources: a Matched Cohort Study of Patients with Common Medical Conditions.

Background: Nursing resources, such as staffing ratios and skill mix, vary across hospitals. Better nursing resources have been linked to better patient outcomes but are assumed to increase costs. The value of investments in nursing resources, in terms of clinical benefits relative to costs, is unclear.

Valuing hospital investments in nursing: multistate matched-cohort study of surgical patients.

Background: There are known clinical benefits associated with investments in nursing. Less is known about their value.

Aims: To compare surgical patient outcomes and costs in hospitals with better versus worse nursing resources and to determine if value differs across these hospitals for patients with different mortality risks.

Using Evidence Factors to Clarify Exposure Biomarkers.

A study has 2 evidence factors if it permits 2 statistically independent inferences about 1 treatment effect such that each factor is immune to some bias that would invalidate the other factor. Because the 2 factors are statistically independent, the evidence they provide can be combined using methods associated with meta-analysis for independent studies, despite using the same data twice in different ways. We illustrate evidence factors, applying them in a new way in investigations that have both an exposure biomarker and a coarse external measure of exposure to a treatment.

Comparing Outcomes and Costs of Medical Patients Treated at Major Teaching and Non-teaching Hospitals: A National Matched Analysis.

Background: Teaching hospitals typically pioneer investment in new technology and cultivate workforce characteristics generally associated with better quality, but the value of this extra investment is unclear.

Objective: Compare outcomes and costs between major teaching and non-teaching hospitals by closely matching on patient characteristics.

Design: Medicare patients at 339 major teaching hospitals (resident-to-bed (RTB) ratios ≥ 0.

Comparing Outcomes and Costs of Surgical Patients Treated at Major Teaching and Nonteaching Hospitals: A National Matched Analysis.

Objective: To compare outcomes and costs between major teaching and nonteaching hospitals on a national scale by closely matching on patient procedures and characteristics.

Background: Teaching hospitals have been shown to often have better quality than nonteaching hospitals, but cost and value associated with teaching hospitals remains unclear.

Methods: A study of Medicare patients at 340 teaching hospitals (resident-to-bed ratios ≥ 0.

Comparing Resource Use in Medical Admissions of Children With Complex Chronic Conditions.

Background: Children with complex chronic conditions (CCCs) utilize a disproportionate share of hospital resources.

Objective: We asked whether some hospitals display a significantly different pattern of resource utilization than others when caring for similar children with CCCs admitted for medical diagnoses.

Research Design: Using Pediatric Health Information System data from 2009 to 2013, we constructed an inpatient Template of 300 children with CCCs, matching these to 300 patients at each hospital, thereby performing a type of direct standardization.