Modelling distributions of Aedes aegypti and Aedes albopictus using climate, host density and interspecies competition.

Florida faces the challenge of repeated introduction and autochthonous transmission of arboviruses transmitted by Aedes aegypti and Aedes albopictus. Empirically-based predictive models of the spatial distribution of these species would aid surveillance and vector control efforts. To predict the occurrence and abundance of these species, we fit a mixed-effects zero-inflated negative binomial regression to a mosquito surveillance dataset with records from more than 200,000 trap days, representative of 53% of the land area and ranging from 2004 to 2018 in Florida. We found an asymmetrical competitive interaction between adult populations of Aedes aegypti and Aedes albopictus for the sampled sites. Wind speed was negatively associated with the occurrence and abundance of both vectors. Our model predictions show high accuracy (72.9% to 94.5%) in validation tests leaving out a random 10% subset of sites and data since 2017, suggesting a potential for predicting the distribution of the two Aedes vectors

Long-term declines in ADLs, IADLs, and mobility among older Medicare beneficiaries

<p>Abstract</p> <p>Background</p> <p>Most prior studies have focused on short-term (≤ 2 years) functional declines. But those studies cannot address aging effects inasmuch as all participants have aged the same amount. Therefore, the authors studied the extent of long-term functional decline in older Medicare beneficiaries who were followed for varying time lengths, and the authors also identified the risk factors associated with those declines.</p> <p>Methods</p> <p>The analytic sample included 5,871 self- or proxy-respondents who had complete baseline and follow-up survey data that could be linked to their Medicare claims for 1993-2007. Functional status was assessed using activities of daily living (ADLs), instrumental ADLs (IADLs), and mobility limitations, with declines defined as the development of two of more new difficulties. Multiple logistic regression analysis was used to focus on the associations involving respondent status, health lifestyle, continuity of care, managed care status, health shocks, and terminal drop.</p> <p>Results</p> <p>The average amount of time between the first and final interviews was 8.0 years. Declines were observed for 36.6% on ADL abilities, 32.3% on IADL abilities, and 30.9% on mobility abilities. Functional decline was more likely to occur when proxy-reports were used, and the effects of baseline function on decline were reduced when proxy-reports were used. Engaging in vigorous physical activity consistently and substantially protected against functional decline, whereas obesity, cigarette smoking, and alcohol consumption were only associated with mobility declines. Post-baseline hospitalizations were the most robust predictors of functional decline, exhibiting a dose-response effect such that the greater the average annual number of hospital episodes, the greater the likelihood of functional status decline. Participants whose final interview preceded their death by one year or less had substantially greater odds of functional status decline.</p> <p>Conclusions</p> <p>Both the additive and interactive (with functional status) effects of respondent status should be taken into consideration whenever proxy-reports are used. Encouraging exercise could broadly reduce the risk of functional decline across all three outcomes, although interventions encouraging weight reduction and smoking cessation would only affect mobility declines. Reducing hospitalization and re-hospitalization rates could also broadly reduce the risk of functional decline across all three outcomes.</p

Measurement and prediction of inpatient case manager workload in a tertiary hospital setting

Thesis: S.M. in Engineering Systems, Massachusetts Institute of Technology, School of Engineering, Institute for Data, Systems, and Society, 2016. In conjunction with the Leaders for Global Operations Program at MIT.Thesis: M.B.A., Massachusetts Institute of Technology, Sloan School of Management, 2016. In conjunction with the Leaders for Global Operations Program at MIT.Cataloged from PDF version of thesis.Includes bibliographical references (pages 197-205).A patient's care needs often extend past discharge from an acute hospital setting. At Massachusetts General Hospital (MGH), inpatient case managers, acting in a discharge planning capacity, help develop and coordinate the execution of plans, specifically tailored for a patient, to ensure these care needs are met. Case managers, and case management leadership, must confront multiple sources of workload variability across different time and scale perspectives. Case managers are assigned a relatively invariant number of cases by floor. Inter-floor workload variability exists because the "typical" case on one floor may require more or less work than the "typical" case on another floor. Inter-case variability is also present; for a given case manager, the concept of a "typical" case has limited value. Some cases require essentially no work from a discharge planning case manager, while other cases can consume many hours, either on a single day, or spread across multiple days. The case characteristics determining the amount of work required of a case manager are not solely, or even primarily, clinical. Instead, discharge disposition, insurance considerations, patient preferences, and a wide array of psycho-social factors, as well as complex interactions among case characteristics, drive the workload for any single case. Finally, the total amount of work required, across all assigned cases, can vary dramatically from day to day. In any discussion of case manager workload, variability, in all of its dimensions, is a fundamental characteristic. From an operational improvement standpoint workload variability has to be fully considered, understood, and accommodated. The current static staffing scheme, based on the number of beds a case manager is responsible for, does not adequately address the observed variability in daily workload. Therefore, the ultimate objective of our work is to develop a candidate staffing scheme and staffing guidelines incorporating requisite dynamic element to address variability in a case manager's daily workload and/or reduce observed upside variability. Since the requisite understanding of workload variability will always prove elusive without a meaningful way to measure workload, in the first, necessary step for our work we develop a method of measuring the amount of work performed by a case manager, for a given case or on a given day. Though the scale for our work metric requires more refined calibration, it allows one to say with a high degree of certainty that "this case required more work than that case" or "this day represented a higher workload for a case manager than that day". The source of the score for a case or day is the work documented in case manager notes. We develop an automated scoring procedure to retrospectively score cases based on the text of case manager notes. At the heart of our text-analytical engine is an augmented bag-of-words approach that preserves the relevant context for a case manager note. Using a regression tree to operate on our text feature vector for a case note results in validation set scoring with an R2 of 0.98 at the case and day level. In validating our scoring methodology case managers were asked to rank a group of cases in order of increasing workload. This ordinal ranking was compared to the ranking derived from our work score and yielded a value for Kendall's coefficient of concordance, W, of 0.98, indicating exceptional agreement. Results using our score provide further indirect support for the validity of our scoring methodology. For example, the top decile of patients by work score accounted for 40% of the total work scored. This is in line with case manager reports that a relatively small number of patients require a disproportionately large amount of case manager time. Our validated work score is then used as a response variable for explanatory and predictive modeling of case manager workload. The predictor variables are derived from a phased framework we developed over the course of our work. That is, distinct phases can be identified on a discharge planning plane as a patient progresses to ultimate discharge. For the majority of cases it is possible to identify, unambiguously, which phase a case is in. Counts of the number of cases in each phase at 04:00 form our predictor variables in projecting the amount of case manager workload required for the upcoming day. Each phase is associated with both a characteristic amount of work and, as importantly, whether a given case will require any case manager work on a given day. This allows us to introduce the concept of an active census or active caseload. It is this concept that allows us to capture a key, under-considered source of variability - whether a case will require any work of a case manager on a given day. Using a regression-based model, the work for a case manager can currently be predicted with an R2 of 0.51 and a case can be predicted as active with an R2 of 0.66. With classification based on a boosted tree, a day can be correctly predicted as high, medium, or low workload with an accuracy of 81%. Two class misclassification error rates (high-as-low or low-as-high) of 7% can currently be achieved. Finally, in a synthesis of all of our work, we present the outline for a dynamic case assignment scheme based on pooling and balancing the number of cases in each phase between case managers within a pool. This can help attenuate the magnitude of high workload days and reduce upside variability.by Jason Edward Stuck.S.M. in Engineering SystemsM.B.A

Cardiac Excrescences of Unusual Origin

Mesothelial/monocytic incidental cardiac excrescences (cardiac MICE) are a rare finding that are most often discovered incidentally either upon echocardiography or invasive cardiovascular procedures. In total, less than 50 known cases have been reported since first being discovered over 30 years ago. They are typically benign lesions; however, there has been a reported case of cardiac MICE being responsible for severe cardiopulmonary compromise and another case of the lesion embolizing leading to cerebral infarctions and ultimately death. Cardiac papillary fibroelastomas are also uncommon lesions found in the heart though they are not as rare as cardiac MICE. They are also benign and are typically attached to valvular surfaces; however, they also can be found as mobile masses. Just as cardiac MICE, they are capable of causing turbulent flow and thrombus formation and have been reported as the cause of ischemic events due to their ability to embolize. We present a case of cardiac MICE and cardiac papillary fibroelastoma in an individual who initially presented with neurologic symptoms concerning for a cerebrovascular accident. The patient was found to have a left ventricular mass composed of both cardiac MICE and cardiac papillary fibroelastomas

The Irvine, Beatties, and Bresnahan (IBB) forelimb recovery scale: An assessment of reliability and validity

The IBB scale is a recently developed forelimb scale for the assessment of fine control of the forelimb and digits after cervical spinal cord injury [SCI; (1)]. The present paper describes the assessment of inter-rater reliability and face, concurrent an