Using Operational Analysis to Improve Access to Pulmonary Function Testing

Background. Timely pulmonary function testing is crucial to improving diagnosis and treatment of pulmonary diseases. Perceptions of poor access at an academic pulmonary function laboratory prompted analysis of system demand and capacity to identify factors contributing to poor access. Methods. Surveys and interviews identified stakeholder perspectives on operational processes and access challenges. Retrospective data on testing demand and resource capacity was analyzed to understand utilization of testing resources. Results. Qualitative analysis demonstrated that stakeholder groups had discrepant views on access and capacity in the laboratory. Mean daily resource utilization was 0.64 (SD 0.15), with monthly average utilization consistently less than 0.75. Reserved testing slots for subspecialty clinics were poorly utilized, leaving many testing slots unfilled. When subspecialty demand exceeded number of reserved slots, there was sufficient capacity in the pulmonary function schedule to accommodate added demand. Findings were shared with stakeholders and influenced scheduling process improvements. Conclusion. This study highlights the importance of operational data to identify causes of poor access, guide system decision-making, and determine effects of improvement initiatives in a variety of healthcare settings. Importantly, simple operational analysis can help to improve efficiency of health systems with little or no added financial investment

The Exact Fill Rate in a Periodic Review Base Stock System under Normally Distributed Demand

This is a post print file as per the journal publisher's requirements. Article deposited according to publisher policy posted on SHERPA/ROMEO, July 27, 2011.In this paper we consider a periodic review order-up-to-level (or base stock) inventory control system under normally distributed demand. For such circumstances an expression for the exact fill rate (fraction of demand satisfied without backordering) has been available in the literature but has not been widely known, let alone used by practitioners. In this paper we redevelop the expression and contrast our derivation with the earlier published one. The paper has two purposes. First, we hope that the reappearance of the exact result in this journal will lead to its wider adoption. Second, showing two contrasting approaches to obtaining the same result may be useful for both research and pedagogical purposes.Ye

The Role of Political Parties in the Organization of Congress

This paper examines theory and evidence on party competition in the U. S. Congress in the allocation of members to committees. Parties allocate members to committees to maximize the joint utility of its members, taking into account how the committees' memberships affect the legislation adopted by the legislature. Parties are constrained by both institutional rules and the heterogeneity of party members' preferences. Interest group ratings from the U.S. House of Representatives provide evidence that the parties stack committees in a manner consistent with the predictions of the theoretical model. Alternative hypotheses explain no more than half the committees in the U. S. Congress, while the party competition hypothesis is consistent with the overall structure of the committees. Model selection tests that nest the party competition and representative majority party hypotheses reveal that the party competition hypothesis is supported by the data while the representative majority party hypothesis is not. The Role of Political Parties in the Organization of Congress Abstract: This paper examines theory and evidence on party competition in the U. S. Congress in the allocation of members to committees. Parties allocate members to committees to maximize the joint utility of its members, taking into account how the committees' memberships affect the legislation adopted by the legislature. Parties are constrained by both institutional rules and the heterogeneity of party members' preferences. Interest group ratings from the U.S. House of Representatives provide evidence that the parties stack committees in a manner consistent with the predictions of the theoretical model. Alternative hypotheses explain no more than half the committees in the U. S. Congress, while the party c..

Learning by Doing, Knowledge Spillovers, and Technological and Organizational Change in High-Altitude Mountaineering

We present an analysis of microlevel data from mountaineering on the 14 peaks over 8,000 m in height during the period 1895-1998. Prior to 1950, no expedition was successful in making an ascent and almost half of expeditions experienced a death, frostbite, or altitude sickness. By the 1990s, however, over half of the expeditions would successfully make an ascent and only about one in seven would experience an adverse outcome. Our objective is to distinguish between the effects of learning by doing and knowledge spillovers versus the effects of changes in technology or economic organization in explaining these results. As we can identify each climber by name and nationality, as well as each expedition team's methods and outcomes, we are able to disentangle the effects of learning at the individual, national, and international levels from effects due to improvements in climbing technology or changes in organizational methods and objectives. We find evidence that both individual learning by doing and learning through knowledge spillovers have contributed to the observed increase in ascent rates and to the decrease in death, frostbite, and altitude sickness rates.learning by doing; knowledge spillovers; technological change; mountaineering

The exact fill rate in a periodic review base stock system under normally distributed demand

In this paper, we consider a periodic review order-up-to-level (or base stock) inventory control system under normally distributed demand. For such circumstances, an expression for the exact fill rate (fraction of demand satisfied without backordering) has been available in the literature, but has not been widely known, let alone used by practitioners. In this paper, we redevelop the expression and contrast our derivation with the earlier published one. The paper has two purposes. First, we hope that the reappearance of the exact result in this journal will lead to its wider adoption. Second, showing two contrasting approaches to obtaining the same result may be useful for both research and pedagogical purposes.Inventory control Base stock Fill rate Normal distribution

Using Operational Analysis to Improve Access to Pulmonary Function Testing

Background. Timely pulmonary function testing is crucial to improving diagnosis and treatment of pulmonary diseases. Perceptions of poor access at an academic pulmonary function laboratory prompted analysis of system demand and capacity to identify factors contributing to poor access. Methods. Surveys and interviews identified stakeholder perspectives on operational processes and access challenges. Retrospective data on testing demand and resource capacity was analyzed to understand utilization of testing resources. Results. Qualitative analysis demonstrated that stakeholder groups had discrepant views on access and capacity in the laboratory. Mean daily resource utilization was 0.64 (SD 0.15), with monthly average utilization consistently less than 0.75. Reserved testing slots for subspecialty clinics were poorly utilized, leaving many testing slots unfilled. When subspecialty demand exceeded number of reserved slots, there was sufficient capacity in the pulmonary function schedule to accommodate added demand. Findings were shared with stakeholders and influenced scheduling process improvements. Conclusion. This study highlights the importance of operational data to identify causes of poor access, guide system decision-making, and determine effects of improvement initiatives in a variety of healthcare settings. Importantly, simple operational analysis can help to improve efficiency of health systems with little or no added financial investment.Peer Reviewe

Modeling patient service centers with simulation and system dynamics

Simulation, Healthcare, Facility design, System dynamics, Case study,