Most existing estimates of the shortage of primary care physicians are based on simple ratios, such as one physician for every 2,500 patients. These estimates do not consider the impact of such ...ratios on patients' ability to get timely access to care. They also do not quantify the impact of changing patient demographics on the demand side and alternative methods of delivering care on the supply side. We used simulation methods to provide estimates of the number of primary care physicians needed, based on a comprehensive analysis considering access, demographics, and changing practice patterns. We show that the implementation of some increasingly popular operational changes in the ways clinicians deliver care-including the use of teams or "pods," better information technology and sharing of data, and the use of nonphysicians-have the potential to offset completely the increase in demand for physician services while improving access to care, thereby averting a primary care physician shortage.
Many service systems have servers with different capabilities and customers with varying needs. One common way this occurs is when servers are hierarchical in their skills or in the level of service ...they can provide. Much of the literature studying such systems relies on an understanding of the relative costs and benefits associated with serving different customer types by the different levels of service. In this work, we focus on estimating these costs and benefits in a complex healthcare setting where the major differentiation among server types is the intensity of service provided. Step-down units (SDUs) were initially introduced in hospitals to provide an intermediate level of care for semicritically ill patients who are not sick enough to require intensive care but not stable enough to be treated in the general medical/surgical ward. One complicating factor is that the needs of customers is sometimes uncertain—specifically, it is difficult to know a priori which level of care a particular patient needs. Using data from 10 hospitals from a single hospital network, we take a data-driven approach to classify patients based on severity and empirically estimate the clinical and operational outcomes associated with routing these patients to the SDU. Our findings suggest that an SDU may be a cost-effective way to treat patients when used for patients who are post-ICU (intensive care unit). However, the impact of SDU care is more nuanced for patients admitted from the emergency department and may result in increased mortality risk and hospital length of stay for patients who should be treated in the ICU. Our results imply that more study is needed when using SDU care this way.
This paper was accepted by Serguei Netessine, operations management.
The problem of determining nurse staffing levels in a hospital environment is a complex task because of variable patient census levels and uncertain service capacity caused by nurse absenteeism. In ...this paper, we combine an empirical investigation of the factors affecting nurse absenteeism rates with an analytical treatment of nurse staffing decisions using a novel variant of the newsvendor model. Using data from the emergency department of a large urban hospital, we find that absenteeism rates are consistent with nurses exhibiting an aversion to higher levels of anticipated workload. Using our empirical findings, we analyze a single-period nurse staffing problem considering both the case of constant absenteeism rate (exogenous absenteeism) as well as an absenteeism rate that is a function of the number of nurses scheduled (endogenous absenteeism). We provide characterizations of the optimal staffing levels in both situations and show that the failure to incorporate absenteeism as an endogenous effect results in understaffing.
This paper was accepted by Yossi Aviv, operations management.
Many primary care offices and other medical practices regularly experience long backlogs for appointments. These backlogs are exacerbated by a significant level of last-minute cancellations or ..."no-shows," which have the effect of wasting capacity. In this paper, we conceptualize such an appointment system as a single-server queueing system in which customers who are about to enter service have a state-dependent probability of not being served and may rejoin the queue. We derive stationary distributions of the queue size, assuming both deterministic as well as exponential service times, and compare the performance metrics to the results of a simulation of the appointment system. Our results demonstrate the usefulness of the queueing models in providing guidance on identifying patient panel sizes for medical practices that are trying to implement a policy of "advanced access."
Mepolizumab was the first licensed anti-IL5 monoclonal antibody for severe eosinophilic asthma (SEA). To date there are few data to confirm its efficacy in the real-world setting or assessment of ...baseline characteristics associated with response.
How do patients with severe eosinophilic asthma respond to mepolizumab in the real world setting and which characteristics are associated with a super-response to this therapy?
We conducted a retrospective review of all patients who received at least 16 weeks of treatment with mepolizumab (100 mg subcutaneously) for SEA at our regional asthma center in the United Kingdom. Clinical data were collected at each 4-week visit. At 16, 24, and 52 weeks, patients were classified as “responders” or “nonresponders.” A response was defined as ≥50% reduction in exacerbations; for patients whose condition requires maintenance oral corticosteroids (mOCS), a response was defined as ≥50% reduction in prednisolone dose. Super responders were defined as exacerbation-free and off mOCS at one year.
Ninety-nine patients were included in the analysis. Asthma exacerbations decreased from a baseline of 4.04 ± 2.57 to 1.86 ± 2.17 per year at one year (54% reduction; P < .001). Sixty-eight patients were receiving mOCS at the time of commencing mepolizumab. By one year, the daily median dose fell from 10 mg (interquartile range, 10 to 15) to 0 mg (interquartile range, 0 to 10; P < .001). Fifty-seven percent of them were able to discontinue mOCS; 72.7% (95% CI, 63.0 to 80.7) of the patients were classified as responders, and 28.3% (95% CI, 20.2 to 38.0) of the patients were classified as super responders. Baseline characteristics associated with responder and super responder status included the presence of nasal polyposis (P = .012), lower baseline Asthma Control Questionnaire 6 (P = .006), a lower BMI (P = .014), and, in those patients receiving mOCS, a significantly lower prednisolone dose at baseline (P = .005). At 16 weeks, the one-year responder status was correctly identified in 80.8% patients; by 24 weeks, this status rose to 92.9%.
In a real-world SEA cohort, treatment with mepolizumab reduced exacerbation frequency and mOCS requirements. Nasal polyposis, a lower BMI, and a lower maintenance prednisolone requirement at baseline were associated with better outcomes. Twelve-month response was identifiable in >90% of patients by week 24.
Benralizumab is an IL5-receptor monoclonal antibody licensed for the treatment of severe eosinophilic asthma (SEA). It has demonstrated efficacy in clinical trials in reducing asthma exacerbation ...rates and maintenance oral corticosteroids (mOCSs).
What is the real-world effectiveness of benralizumab and what baseline characteristics are associated with response to therapy?
We assessed outcomes in all SEA patients who began benralizumab treatment at our specialist center. At each dosing visit, exacerbation history, mOCS dose, spirometry, and Asthma Control Questionnaire (ACQ6) and Mini-Asthma Quality of Life Questionnaire (mAQLQ) scores were recorded. Response to treatment was defined as a reduction of ≥ 50% in annualized exacerbation rate (AER) or in mOCS dose after 48 weeks of treatment. Super response was defined as zero exacerbations and no mOCSs for asthma.
One hundred thirty patients were included in the analysis. At 48 weeks, a 72.8% reduction in AER was noted, from 4.92 ± 3.35 per year in the year preceding biologic treatment to 1.34 ± 1.71 per year (P < .001), including 57 patients (43.8%) who were exacerbation-free with benralizumab. In those receiving mOCSs (n = 74 56.9%), the median daily prednisolone dose fell from 10 mg (interquartile range, 5-20 mg) to 0 mg (interquartile range, 0-5 mg; P < .001), and 38 of 74 patients (51.4%) were able to discontinue mOCS therapy. Clinically and statistically significant improvements were found in ACQ6 scores, mAQLQ scores, and FEV1. Overall, 51 patients (39%) met the super responder definition and 112 patients (86%) met the responder definition. The optimal regression model of super responders vs other responders included baseline characteristics associated with a strongly eosinophilic phenotype and less severe disease. Eighteen patients (13.8%) were nonresponders to benralizumab. Evidence of chronic airway infection was observed in 6 of 18 patients, and an increase in the blood eosinophil count consistent with the development of anti-drug antibodies was observed in 5 of 18 patients.
In a large real-world SEA cohort, benralizumab led to significant improvements in all clinical outcome measures. A lack of response was seen in a minority of patients and should be a focus for future investigation.
Nursing care is arguably the single biggest factor in both the cost of hospital care and patient satisfaction. Inadequate inpatient nursing levels have also been cited as a significant factor in ...medical errors and emergency room overcrowding. Yet, there is widespread dissatisfaction with the current methods of determining nurse staffing levels, including the most common one of using minimum nurse-to-patient ratios. In this paper, we represent the nursing system as a variable finite-source queuing model. We develop a reliable, tractable, easily parameterized two-dimensional model to approximate the actual interdependent dynamics of bed occupancy levels and demands for nursing. We use this model to show how unit size, nursing intensity, occupancy levels, and unit length-of-stay affect the impact of nursing levels on performance and thus how inflexible nurse-to-patient ratios can lead to either understaffing or overstaffing. The model is also useful for estimating the impact of nurse staffing levels on emergency department overcrowding.
Citizens have long contributed to scientific research about the environment through volunteer environmental monitoring programs. Their participation has also resulted in outcomes for themselves, ...their communities, and the environment. This research synthesizes 35 peer-reviewed journal articles that reported such outcomes through 2012. This collection of articles was derived from a pool of 436 peer-reviewed journal articles about participatory environmental monitoring. Reported outcomes for participants and communities ranged from increasing personal knowledge and community awareness to changing attitudes and behaviors, building social capital, and ultimately, influencing change in natural resource management and policies. Mixed results were reported in regard to citizen participation in natural resource decision-making processes and in terms of participant knowledge gain. Future research recommendations that address identified knowledge gaps include the following: (1) assessing knowledge beyond the basic content of the subject of monitoring to better address the value of volunteer environmental monitoring as a public participation tool; (2) conducting independent research across programs to enable null or negative outcome reporting, understand commonalities of outcomes across programs, and make linkages between outcomes and program characteristics; (3) carrying out rigorous research that includes data collection and statistical analysis focused on the effectiveness of citizen participation in decision making; (4) assessing the time component of outcome achievement to inform the volunteer monitoring community; and (5) conducting additional research to identify changes in attitudes and behaviors, particularly geared toward minimizing losses in biodiversity and impacts of climate change.
An effective vaginal microbicide could reduce human immunodeficiency virus type 1 (HIV-1) transmission to women. Among microbicide candidates in clinical development is Maraviroc (MVC), a ...small-molecule drug that binds the CCR5 co-receptor and impedes HIV-1 entry into cells. Delivered systemically, MVC reduces viral load in HIV-1-infected individuals, but its ability to prevent transmission is untested. We have now evaluated MVC as a vaginal microbicide with use of a stringent model that involves challenge of rhesus macaques with a high-dose of a CCR5-using virus, SHIV-162P3. Gel-formulated, prescription-grade MVC provided dose-dependent protection, half-maximally at 0.5 mM (0.25 mg/mL). The duration of protection was transient; the longer the delay between MVC application and virus challenge, the less protection (half life of ∼4 h). As expected, MVC neither protected against challenge with a CXCR4-using virus, SHIV-KU1, nor exacerbated postinfection viremia. These findings validate MVC development as a vaginal microbicide for women and should guide clinical programs.
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