Papers and patents are becoming less disruptive over time.

Theories of scientific and technological change view discovery and invention as endogenous processes1,2, wherein previous accumulated knowledge enables future progress by allowing researchers to, in Newton's words, 'stand on the shoulders of giants'3-7. Recent decades have witnessed exponential growth in the volume of new scientific and technological knowledge, thereby creating conditions that should be ripe for major advances8,9. Yet contrary to this view, studies suggest that progress is slowing in several major fields10,11. Here, we analyse these claims at scale across six decades, using data on 45 million papers and 3.9 million patents from six large-scale datasets, together with a new quantitative metric-the CD index12-that characterizes how papers and patents change networks of citations in science and technology. We find that papers and patents are increasingly less likely to break with the past in ways that push science and technology in new directions. This pattern holds universally across fields and is robust across multiple different citation- and text-based metrics1,13-17. Subsequently, we link this decline in disruptiveness to a narrowing in the use of previous knowledge, allowing us to reconcile the patterns we observe with the 'shoulders of giants' view. We find that the observed declines are unlikely to be driven by changes in the quality of published science, citation practices or field-specific factors. Overall, our results suggest that slowing rates of disruption may reflect a fundamental shift in the nature of science and technology.

Primary Care Provider Demographics and Engagement in Interprofessional Collaboration.

INTRODUCTION: Interprofessional care contributes to all components of the quadruple aim. While previous research has identified many facilitators and barriers to the provision of interprofessional care, whether demographic differences might influence the extent to which providers collaborate interprofessionally remains unknown. METHODS: Using electronic health record data, we characterized the level of primary care providers' (PCPs') interprofessional collaboration based on the percent of their patients who had a visit with an interprofessional team member over a 14-month period. We then obtained demographic data, including gender, years in practice, and provider type, from the electronic health record and publicly available sources. Subsequently, we used linear regression to predict the PCPs' level of interprofessional collaboration based on demographic indicators. RESULTS: The median of each PCP's patients who had a visit with an interprofessional team member during the study period was 12.6%. After controlling for the average age of the PCP's patient panel, the PCP's years in practice, and the PCP's clinic, when compared with male PCPs, approximately 2% more of patients cared for by female PCPs had a visit with an interprofessional team member. CONCLUSION: Female providers are more likely to share their patients with an interprofessional team.

Care fragmentation predicts 90-day durable ventricular assist device outcomes.

OBJECTIVES: To examine whether fragmentation of care is associated with worse in-hospital and 90-day outcomes following durable ventricular assist device (VAD) implant. STUDY DESIGN: Cohort study. METHODS: This study was conducted using Medicare claims linked to the Society of Thoracic Surgeons (STS) Interagency Registry for Mechanically Assisted Circulatory Support (Intermacs) among patients undergoing VAD implant between July 2009 and April 2017. Medicare data were used to measure fragmentation of the multidisciplinary care delivery network for the treating hospital, based on providers' history of shared patients within the previous year. STS Intermacs data were used for risk adjustment and outcomes ascertainment. Hospitals were sorted into terciles based on the degree of network fragmentation, measured as the mean number of links separating providers in the network. Multivariable regression was used to associate network fragmentation with 90-day death or infection risk. RESULTS: The cohort included 5159 patients who underwent VAD implant, with 11.2% dying and 27.6% experiencing an infection within 90 days after implant. After adjustment, a 1-unit increase in network fragmentation was associated with an increase of 0.179 in the probability of in-hospital infection and an increase of 0.183 in the probability of 90-day infection (both P < .05). Similar results were observed in models of the numbers of in-hospital and 90-day infections. Network fragmentation was predictive of the probability of 90-day mortality, although this relationship was not significant after adjustment. CONCLUSIONS: Care delivery network fragmentation is associated with higher in-hospital and 90-day infection rates following durable VAD implant. These networks may serve as novel targets for enhancing outcomes for patients undergoing VAD implant.

Association Between Care Fragmentation and Total Spending After Durable Left Ventricular Device Implant: A Mediation Analysis of Health Care-Associated Infections Within a National Medicare-Society of Thoracic Surgeons Intermacs Linked Dataset.

BACKGROUND: Care fragmentation is associated with higher rates of infection after durable left ventricular assist device (LVAD) implant. Less is known about the relationship between care fragmentation and total spending, and whether this relationship is mediated by infections. METHODS: Total payments were captured from admission to 180 days post-discharge. Drawing on network theory, a measure of care fragmentation was developed based on the number of shared patients among providers (ie, anesthesiologists, cardiac surgeons, cardiologists, critical care specialists, nurse practitioners, physician assistants) caring for 4,987 Medicare beneficiaries undergoing LVAD implantation between July 2009 - April 2017. Care fragmentation was measured using average path length, which describes how efficiently information flows among network members; longer path length indicates greater fragmentation. Terciles based on the level of care fragmentation and multivariable regression were used to analyze the relationship between care fragmentation and LVAD payments and mediation analysis was used to evaluate the role of post-implant infections. RESULTS: The patient cohort was 81% male, 73% white, 11% Intermacs Profile 1 with mean (SD) age of 63.1 years (11.1). The mean (SD) level of care fragmentation in provider networks was 1.7 (0.2) and mean (SD) payment from admission to 180 days post-discharge was $246,905 ($109,872). Mean (SD) total payments at the lower, middle, and upper terciles of care fragmentation were $250,135 ($111,924), $243,288 ($109,376), and $247,290 ($108,241), respectively. In mediation analysis, the indirect effect of care fragmentation on total payments, through infections, was positive and statistically significant (ß=16032.5, p=0.008). CONCLUSIONS: Greater care fragmentation in the delivery of care surrounding durable LVAD implantation is associated with a higher incidence of infections, and consequently, higher payments for Medicare beneficiaries. Interventions to reduce care fragmentation may reduce the incidence of infections and in turn enhance the value of care for patients undergoing durable LVAD implantation.

Understanding Melanoma Talk on Twitter: The Lessons Learned and Missed Opportunities.

BACKGROUND: Melanoma is the third most common cause of cancer and the deadliest form of skin cancer among 17-39 year-olds in the United States. Melanoma is a critical public health issue with a substantial economic burden. Cases and associated burdens, however, could be prevented with a greater awareness of, and interventions related to, skin cancer and melanoma-related preventive behaviors. In fact, as social media use is close to ubiquitous, it represents a potential communication modality. However, more research is needed to understand the current state of melanoma-related information exchanged between Twitter users. This study aimed to understand the different types of users controlling the melanoma-related information diffusion and conversation themes on Twitter. METHODS: Tweets (n = 692) were imported from Twitter between 1 and 31 May 2021 using the Twitter public API; and uploaded to NodeXL to conduct a social network analysis. RESULTS: Health professionals and organizations with medical backgrounds were the main content producers, disseminators, and top influencers. However, information diffusion is slow and uneven among users. Additionally, conversations lacked a focus on preventive behaviors. CONCLUSION: Twitter is a potential platform for the targeted outreach of individuals in melanoma awareness campaigns. This study provides insights maximizing the effectiveness of Twitter as a communication modality. Our findings can help guide the development of customized content and interventions during melanoma awareness campaigns.

Correction: Understanding and Addressing Variation in Health Care-Associated Infections After Durable Ventricular Assist Device Therapy: Protocol for a Mixed Methods Study.

[This corrects the article DOI: 10.2196/14701.].

Authorship Correction: Understanding and Addressing Variation in Health Care-Associated Infections After Durable Ventricular Assist Device Therapy: Protocol for a Mixed Methods Study.

[This corrects the article DOI: 10.2196/14701.].

Understanding and Addressing Variation in Health Care-Associated Infections After Durable Ventricular Assist Device Therapy: Protocol for a Mixed Methods Study.

BACKGROUND: Durable ventricular assist device (VAD) therapy is reserved for patients with advanced heart failure who have a poor estimated 1-year survival. However, despite highly protocolized management processes, patients are at a unique risk for developing a health care-associated infection (HAI). Few studies have examined optimal strategies for HAI prevention after durable VAD implantation, despite variability in rates across centers and their impact on short- and long-term outcomes. OBJECTIVE: The objective of this study is to develop recommendations for preventing the most significant HAIs after durable VAD implantation. The study has 3 specific aims: (1) identify determinants of center-level variability in HAI rates, (2) develop comprehensive understanding of barriers and facilitators for achieving low center-level HAI rates, and (3) develop and disseminate a best practices toolkit for preventing HAIs that accommodates various center contexts. METHODS: This is a sequential mixed methods study starting with a cross-sectional assessment of current practices. To address aim 1, we will conduct (1) a systematic review of HAI prevention studies and (2) in-depth quantitative analyses using administrative claims, in-depth clinical data, and organizational surveys of VAD centers. For aim 2, we will apply a mixed methods patient tracer assessment framework to conduct semistructured interviews, field observations, and document analysis informed by findings from aim 1 at 5 high-performing (ie, low HAIs) and 5 low-performing (ie, high HAI) centers, which will be examined using a mixed methods case series analysis. For aim 3, we will build upon the findings from the previous aims to develop and field test an HAI preventive toolkit, acquire stakeholder input at an annual cardiac surgical conference, disseminate the final version to VAD centers nationwide, and conduct follow-up surveys to assess the toolkit's adoption. RESULTS: The project was funded by the Agency for Healthcare Research and Quality in 2018 and enrollment for the overall project is ongoing. Data analysis is currently under way and the first results are expected to be submitted for publication in 2019. CONCLUSIONS: This mixed methods study seeks to quantitatively assess the determinants of HAIs across clinical centers and qualitatively identify the context-specific facilitators and barriers for attaining low HAI rates. The mixed data findings will be used to develop and disseminate a stakeholder-acceptable toolkit of evidence-based HAI prevention recommendations that will accommodate the specific contexts and needs of VAD centers. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/14701.

Informal Clinical Integration in Medicare Accountable Care Organizations and Mortality Following Coronary Artery Bypass Graft Surgery.

BACKGROUND: Accountable care organizations' (ACOs') focus on formal clinical integration to improve outcomes overlooks actual patterns of provider interactions around shared patients. OBJECTIVE: To determine whether such informal clinical integration relates to a health system's performance in an ACO. RESEARCH DESIGN: We analyzed national Medicare data (2008-2014), identifying beneficiaries who underwent coronary artery bypass grafting (CABG). After determining which physicians delivered care to them, we aggregated across episodes to construct physician networks for each health system. We used network analysis to measure each system's level of informal clinical integration (defined by cross-specialty ties). We fit regression models to examine the association between a health system's CABG mortality rate and ACO participation, conditional on informal clinical integration. SUBJECTS: Beneficiaries age 66 and older undergoing CABG. MEASURES: Ninety-day CABG mortality. RESULTS: Over the study period, 3385 beneficiaries were treated in 161 ACO-participating health systems. The remaining 49,854 were treated in 875 nonparticipating systems or one of the 161 ACO-participating systems before the ACO start date. ACO systems with higher levels of informal clinical integration had lower CABG mortality rates than nonparticipating ones (2.8% versus 5.5%; P<0.01); however, there was no difference based on ACO participation for health systems with lower to relatively moderate informal clinical integration. Regression results corroborate this finding (coefficient for interaction between ACO participation and informal clinical integration level is -0.25; P=0.01). CONCLUSIONS: Formal clinical integration through ACO participation may be insufficient to improve outcomes. Health systems with higher informal clinical integration may benefit more from ACO participation.

Physician referral patterns and racial disparities in total hip replacement: A network analysis approach.

BACKGROUND: Efforts to reduce racial disparities in total hip replacement (THR) have focused mainly on patient behaviors. While these efforts are no doubt important, they ignore the potentially important role of provider- and system-level factors, which may be easier to modify. We aimed to determine whether the patterns of interaction among physicians around THR episodes differ in communities with low versus high concentrations of black residents. MATERIALS AND METHODS: We analyzed national Medicare claims from 2008 to 2011, identifying all fee-for-service beneficiaries who underwent THR. Based on physician encounter data, we then mapped the physician referral networks at the hospitals where beneficiaries' procedures were performed. Next, we measured two structural properties of these networks that could affect care coordination and information sharing: clustering, and the number of external ties. Finally, we estimated multivariate regression models to determine the relationship between the concentration of black residents in the community [as measured by the hospital service area (HSA)] served by a given network and each of these 2 network properties. RESULTS: Our sample included 336,506 beneficiaries (mean age 76.3 ± SD), 63.1% of whom were women. HSAs with higher concentrations of black residents tended to be more impoverished than those with lower concentrations. While HSAs with higher concentrations of black residents had, on average, more acute care beds and medical specialists, they had fewer surgeons per capita than those with lower concentrations. After adjusting for these differences, we found that HSAs with higher concentrations of black residents were served by physician referral networks that had significantly higher within-network clustering but fewer external ties. CONCLUSIONS: We observed differences in the patterns of interaction among physicians around THR episodes in communities with low versus high concentrations of black residents. Studies investigating the impact of these differences on access to quality providers and on THR outcomes are needed.

Repeated, Close Physician Coronary Artery Bypass Grafting Teams Associated with Greater Teamwork.

OBJECTIVE: To determine whether observed patterns of physician interaction around shared patients are associated with higher levels of teamwork as perceived by physicians. DATA SOURCES/STUDY SETTING: Michigan Medicare beneficiaries who underwent coronary artery bypass grafting (CABG) procedures at 24 hospitals in the state between 2008 and 2011. STUDY DESIGN: We assessed hospital teamwork using the teamwork climate scale in the Safety Attitudes Questionnaire. After aggregating across CABG discharges at these hospitals, we mapped the physician referral networks (including both surgeons and nonsurgeons) that served them and measured three network properties: (1) reinforcement, (2) clustering, and (3) density. We then used multilevel regression models to identify associations between network properties and teamwork at the hospitals on which the networks were anchored. PRINCIPAL FINDINGS: In hospitals where physicians repeatedly cared for patients with the same colleagues, physicians perceived better teamwork (ß-reinforcement = 3.28, p = .003). When physicians who worked together also had other colleagues in common, the reported teamwork was stronger (ß clustering = 1.71, p = .001). Reported teamwork did not change when physicians worked with a higher proportion of other physicians at the hospital (ß density = -0.58, p = .64). CONCLUSION: In networks with higher levels of reinforcement and clustering, physicians perceive stronger teamwork, perhaps because the strong ties between them create a shared understanding; however, sharing patients with more physicians overall (i.e., density) did not lead to stronger teamwork. Clinical and organizational leaders may consider designing the structure of clinical teams to increase interactions with known colleagues and repeated interactions between providers.

Association of Informal Clinical Integration of Physicians With Cardiac Surgery Payments.

Importance: To reduce inefficiency and waste associated with care fragmentation, many current programs target greater clinical integration among physicians. However, these programs have led to only modest Medicare spending reductions. Most programs focus on formal integration, which often bears little resemblance to actual physician interaction patterns. Objectives: To examine how physician interaction patterns vary between health systems and to assess whether variation in informal integration is associated with care delivery payments. Design, Setting, and Participants: National Medicare data from January 1, 2008, through December 31, 2011, identified 253 545 Medicare beneficiaries (aged ≥66 years) from 1186 health systems where Medicare beneficiaries underwent coronary artery bypass grafting (CABG) procedures. Interactions were mapped between all physicians who treated these patients-including primary care physicians and surgical and medical specialists-within a health system during their surgical episode. The level of informal integration was measured in these networks of interacting physicians. Multivariate regression models were fitted to evaluate associations between payments for each surgical episode made on a beneficiary's behalf and the level of informal integration in the health system where the patient was treated. Exposures: The informal integration level of a health system. Main Outcomes and Measures: Price-standardized total surgical episode and component payments. Results: The total 253 545 study participants included 175 520 men (69.2%; mean [SD] age, 74.51 [5.75] years) and 78 024 women (34.3%; 75.67 [5.91] years). One beneficiary of the 253 545 participants did not have sex information. The low level of informal clinical integration included 84 598 patients (33.4%; mean [SD] age, 75.00 [5.93] years); medium level, 84 442 (33.30%; 74.94 [5.87] years); and high level, 84 505 (33.34%; 74.66 [5.72] years) (P < .001). Informal integration levels varied across health systems. After adjusting for patient, health-system, and community factors, higher levels of informal integration were associated with significantly lower total episode and component payments (ß coefficients for informal integration were -365.87 [95% CI, -451.08 to -280.67] for total episode payments, -182.63 [-239.80 to -125.46] for index hospitalization, -43.13 [-55.53 to -30.72] for physician services, -74.48 [-103.45 to -45.51] for hospital readmissions, and -62.04 [-88.00 to -36.07] for postacute care; P < .001 for each association). When beneficiaries were treated in health systems with higher informal integration, the greatest savings of lower estimated payments were from hospital readmissions (13.0%) and postacute care services (5.8%). Conclusions and Relevance: Informal integration is associated with lower spending. Although most programs that seek to promote clinical integration are focused on health systems' formal structures, policy makers may also want to address informal integration.

Identifying Natural Alignments Between Ambulatory Surgery Centers and Local Health Systems: Building Broader Communities of Surgical Care.

OBJECTIVE: To develop and compare methods for identifying natural alignments between ambulatory surgery centers (ASCs) and hospitals that anchor local health systems. MEASURES: Using all-payer data from Florida's State Ambulatory Surgery and Inpatient Databases (2005-2009), we developed 3 methods for identifying alignments between ASCS and hospitals. The first, a geographic proximity approach, used spatial data to assign an ASC to its nearest hospital neighbor. The second, a predominant affiliation approach, assigned an ASC to the hospital with which it shared a plurality of surgeons. The third, a network community approach, linked an ASC with a larger group of hospitals held together by naturally occurring physician networks. We compared each method in terms of its ability to capture meaningful and stable affiliations and its administrative simplicity. RESULTS: Although the proximity approach was simplest to implement and produced the most durable alignments, ASC surgeon's loyalty to the assigned hospital was low with this method. The predominant affiliation and network community approaches performed better and nearly equivalently on these metrics, capturing more meaningful affiliations between ASCs and hospitals. However, the latter's alignments were least durable, and it was complex to administer. CONCLUSIONS: We describe 3 methods for identifying natural alignments between ASCs and hospitals, each with strengths and weaknesses. These methods will help health system managers identify ASCs with which to partner. Moreover, health services researchers and policy analysts can use them to study broader communities of surgical care.

Association Between Physician Teamwork and Health System Outcomes After Coronary Artery Bypass Grafting.

BACKGROUND: Patients undergoing coronary artery bypass grafting (CABG) must often see multiple providers dispersed across many care locations. To test whether teamwork (assessed with the bipartite clustering coefficient) among these physicians is a determinant of surgical outcomes, we examined national Medicare data from patients undergoing CABG. METHODS AND RESULTS: Among Medicare beneficiaries who underwent CABG between 2008 and 2011, we mapped relationships between all physicians who treated them during their surgical episodes, including both surgeons and nonsurgeons. After aggregating across CABG episodes in a year to construct the physician social networks serving each health system, we then assessed the level of physician teamwork in these networks with the bipartite clustering coefficient. Finally, we fit a series of multivariable regression models to evaluate associations between a health system's teamwork level and its 60-day surgical outcomes. We observed substantial variation in the level of teamwork between health systems performing CABG (SD for the bipartite clustering coefficient was 0.09). Although health systems with high and low teamwork levels treated beneficiaries with comparable comorbidity scores, these health systems differed over several sociocultural and healthcare capacity factors (eg, physician staff size and surgical caseload). After controlling for these differences, health systems with higher teamwork levels had significantly lower 60-day rates of emergency department visit, readmission, and mortality. CONCLUSIONS: Health systems with physicians who tend to work together in tightly-knit groups during CABG episodes realize better surgical outcomes. As such, delivery system reforms focused on building teamwork may have positive effects on surgical care.

Assessing the reach of health reform to outpatient surgery with social network analysis.

OBJECTIVE: To assess the proportion of outpatient surgery currently delivered in ambulatory surgery centers (ASCs) unconnected to nearby hospitals. BACKGROUND: The ASC as a site for outpatient surgery represents one of the fastest growing sectors in health care. Because most are freestanding, ASCs may have little connection to local health systems, possibly placing them outside health reform's reach. METHODS: Using all-payer data from Florida (2005-2009), we identified all ASCs and hospitals active in the state. Using the tools of social network analysis, we then measured each ASC's strength of connection to nearby hospitals on the basis of the number of surgeons shared between facilities. Finally, we determined the proportion of all procedures and charges accounted for by (1) ASCs that are strongly connected to their local health system, (2) those that are weakly connected, and (3) those that are unconnected. RESULTS: Of the 1.4 million procedures performed in Florida ASCs each year, fewer than 250,000 occur at unconnected and weakly connected ASCs. Put differently, 83% of the $4.3 billion in charges for ASC-based care originate from facilities that have substantial integration with their local health system. Although weakly and strongly connected ASCs are similar from an organizational perspective, unconnected ones tend to focus on a single specialty (P = 0.026) and are staffed by fewer physicians (P = 0.013). Furthermore, there is a trend toward fewer unconnected ASCs over time (P = 0.080). CONCLUSIONS: Most ASCs are strongly connected to their local health system. Thus, efforts to constrain spending should target population-based rates of surgery, not unconnected ASCs.

Differences between physician social networks for cardiac surgery serving communities with high versus low proportions of black residents.

BACKGROUND: Compared with white patients, black patients are more likely to undergo cardiac surgery at low-quality hospitals, even when they live closer to high-quality ones. Opportunities for organizational interventions to alleviate this problem remain elusive. OBJECTIVES: To explore physician isolation in communities with high proportions of black residents as a factor contributing to racial disparities in access to high-quality hospitals for cardiac surgery. RESEARCH DESIGN: Using national Medicare data (2008-2011), we mapped physician social networks at hospitals where coronary artery bypass grafting procedures were performed, measuring their degree of connectedness. We then fitted a series of multivariate regression models to examine for associations between physician connectedness and the proportion of black residents in the hospital service area (HSA) served by each network. MEASURES: Measures of physician connectedness (ie, repeat-tie fraction, clustering, and number of external ties). RESULTS: After accounting for regional differences in healthcare capacity, the social networks of physicians practicing in areas with more black residents varied in many important respects from those of HSAs with fewer black residents. Physicians serving HSAs with many black residents had a smaller number of repeated interactions with each other than those in other HSAs (P<0.001). When these physicians did interact, they tended to assemble in smaller groups of highly interconnected colleagues (P<0.001). They also had fewer interactions with physicians outside their immediate geographic area (P=0.048). CONCLUSIONS: Physicians in HSAs with many black residents are more isolated than those in HSAs with fewer black residents. This isolation may negatively impact on care coordination and information sharing. As such, planned delivery system reforms that encourage minorities to seek care within their established local networks may further exacerbate existing surgical disparities.

Bis(4,4'-bipyridinium) hexacyanoplatinate(IV) bis(4,4'-bipyridine).

In the title compound, (C10H9N2)2[Pt(CN)6].2C10H8N2 or [(Hbpy)+]2[Pt(CN)6](2-).2bpy, where bpy is 4,4'-bipyridine, the Hbpy+ cations and bpy molecules form a hydrogen-bonded two-dimensional cationic approximately square grid parallel to the (110) plane. The [Pt(CN)6]2- dianions reside in the cavities within this grid, with the nitrile N atoms forming weak hydrogen bonds with the CH groups in the cationic lattice.