A meta-narrative review of electronic patient records

This session comprises four papers that consider how systematic review methods may be developed in order to make the best use of complex evidence in education and health. The methods and approaches reflected upon in these papers are not drawn from a single research tradition, but share a common goal of broadening the methodological scope of systematic reviews and better understanding the utilisation of knowledge produced in this way. The first paper (Henry Potts) reports an ongoing review using a meta-narrative approach to make sense of the diverse sources of knowledge regarding electronic patient records. The review method has stressed the importance of understanding knowledge from within the research tradition in which it was produced; it is argued that this has important implications for the way that evidence is utilised in the policy making process. The second paper (Geoff Wong) reflects upon the experience of using an explicit realist approach in the synthesis of the evidence in Internet based learning. This realist synthesis offers a method of making sense of the highly heterogeneous and context dependent evidence which exists in this field thus enabling greater insights into what makes such educational interventions ‘work’. The third paper (Rod Sheaff) reports a review of the predominantly qualitative research literature on organisational structures and their impacts upon policy outcomes in health systems. A scoping study found 14389 relevant papers of which 1568 were selected for review. These studies were very variable in the amount and quality of the qualitative data, hence 'evidence', which they reported. The paper describes an attempt to adapt realist methods so as to synthesise such bodies of research in ways which take account of this variation in the strength of qualitative evidence. The fourth paper (Mark Pearson) draws upon the work of Donald Campbell and colleagues in order to gain a fuller understanding of how systematic reviews are utilised in the policy making process. It is argued that interpretive approaches to understanding policy making (such as rhetorical analysis) need to be tempered with a more nuanced understanding of research validity. The case is made that interpretive approaches not only can, but should, be melded with research validity to increase understanding of the policy making process

Valuing Private and Public Greenspace Using Remotely Sensed Vegetation Indices

In a typical metropolitan area, greenspace varies substantially in its quality and extent. Remotely sensed vegetation index data is used to characterize the heterogeneity in private and public greenspace (riparian corridors) in metropolitan Tucson, Arizona. This data set enables the researcher to test if: (1) greenness is a significant determinant of house price variation in this desert city; and (2) whether there is an interaction between public and private greenspace. Private greenspace amenities can be endogenously improved by homeowners as a complement or substitute for the greenspace that is publicly provided, whereas public greenspace might be exogenous or endogenous depending on households ability to pressure the local government to protect or restore public greenspace. The results of a Hausman test indicate that endogeneity is a problem in the dataset and therefore an instrumental variable two stage least squares estimation is used. The results of this analysis indicate that homebuyers in the study area have preferences for both greener lots and greener riparian corridors and that private and public greenspace appear to be substitutes. Results are robust across multiple identification strategies designed to address potential endogeneity. The study results could have fundamental implications for the efficient use of limited water supplies in this semi-arid metropolitan area.Resource /Energy Economics and Policy,

Do Homebuyers Care about the 'Quality' of Natural Habitats?

We study if homebuyers in Tucson, Arizona care about the condition of natural habitats and if they have preferences between natural and manmade habitats. Using field work data we examine whether homebuyers willingness to pay is influenced by the biological condition of the neighboring riparian habitat and how homebuyers value alternative manmade green areas, specifically golf courses. We also explore the relationship between the field data and remote sensing vegetation indices. The results of a hedonic analysis of houses that sold within 0.2 miles of 51 stratified-random selected riparian survey sites in Tucson, Arizona reveals that homebuyers significantly value habitat quality and negatively value manmade park-like features. Homebuyers are willing to pay twenty percent more to live near a riparian corridor that is densely vegetated and contains more shrub and tree species, particularly species that are dependent on perennial water flow. These environmental premiums are significant, outweighing structural factors such as an additional garage or swimming pool. Likewise, proximity to a riparian habitat with low biological quality or to a golf course lowers property values.Land Economics/Use,

How Do Homebuyers Value Different Types of Green Space?

It is important to understand tradeoffs in preferences for natural and constructed green space in semi-arid urban areas because these lands compete for scarce water resources. We perform a hedonic study using high resolution, remotely-sensed vegetation indices and house sales records. We find that homebuyers in the study area prefer greener lots, greener neighborhoods, and greener nearby riparian corridors, and they pay premiums for proximity to green space amenities. The findings have fundamental implications for the efficient allocation of limited water supplies between different types of green space and for native vegetation conservation in semi-arid metropolitan areas.hedonic model, locally weighted regression, spatial, open space, golf course, park, riparian, Consumer/Household Economics, Land Economics/Use,

On some physics to consider in numerical simulation of erosive cavitation

This paper discusses several mechanisms in erosive cavitation, which are all important to capture, and study, when assessing the risk of erosion. In particular we introduce the concept of primary and secondary cavitation in order to put emphasis on a particular class of mechanisms: cavitation created in the secondary flow field governed by, e.g., a shedding or collapse of a primary created cavity. These secondary cavities are almost always erosive and have previously not been well described in the literature. The role of cloud cavitation is partly reconsidered and a hypothesis for development of vortex group cavitation, a type of secondary cavitation, is presented. An underlying part of the discussion is how the described cavitation mechanisms influence numerical simulation of cavitation nuisance.http://deepblue.lib.umich.edu/bitstream/2027.42/84223/1/CAV2009-final180.pd

A systematic review of electronic patient records using the meta-narrative approach: Empirical findings and methodological challenges.

Systematic reviews are central to the enterprise of evidence-based medicine (EBM). However, traditional ‘Cochrane’ reviews have major limitations, especially when dealing with heterogeneous methodologies or an applied setting. The meta-narrative review (see Soc Sci Med 2005; 61: 417-30) is one of several new methods that seek to address pragmatic policy-level questions via broad-based literature reviews. Inspired by Kuhn, meta-narrative review takes a historical and paradigmatic approach to considering different areas of research activity. As an interpretive tool, the approach seeks distinct research traditions, each with its own meta-narrative. We then use these ‘stories of how research unfolded’ as a way of making sense of a diverse literature. Incommensurability between different traditions is seen not as a problem to be lamented or resolved but as a window to higher-order explanations about the nuances of empirical data and what these nuances mean for different applied situations. Having originally developed the meta-narrative method for a study of the diffusion of innovations in healthcare, we are now applying it in a review of the electronic patient record (EPR) in an organizational context. We have collated some 600 papers and books across multiple research traditions including health informatics, information systems research, computer-supported cooperative work (CSCW) and sociology. This very contemporary topic area is raising interesting methodological questions. For example, the EPR literature does not comprise as cleanly delineable traditions for four main reasons: 1. Information and communications technology research is a particularly fast-moving field, so paradigm shifts are relatively common (e.g. the rise of CSCW out of human-computer interaction research). 2. In the electronic age, it is easy for researchers to explore beyond their own discipline and ‘borrow’ theories, ideas and methods from elsewhere. Journal editors may commission overviews from experts in another tradition; authors may explicitly address an audience in another tradition. Research traditions can begin to converge (e.g. papers bringing together CSCW, information systems research and STS). 3. Some researchers are adept ‘boundary spanners’, writing for a number of different academic audiences and adapting their theoretical pedigree to fit (e.g. Marc Berg). 4. Some traditions are characterized not by a single unified paradigm but by active dialogue between competing paradigms (e.g. ‘hard’ versus ‘soft’ perspectives on knowledge management). This work contributes to the STS literature by critically questioning the nature of rigour in secondary research. The EBM movement values ‘Cochrane’ reviews because they meet positivist criteria (e.g. they are rational, objective, replicable, data-led, and transferable across contexts). In contrast, the meta-narrative review is interpretive, reflexive, problem-oriented and work-led, and makes no claim to either replicability or transferability. Rigour is redefined in terms of plausibility, authenticity and usefulness – raising the radical suggestion that the evidence base for key policy decisions can never be set in stone. Systematic reviews are central to the enterprise of evidence-based medicine (EBM). However, traditional ‘Cochrane’ reviews have major limitations, especially when dealing with heterogeneous methodologies or an applied setting. The meta-narrative review (see Soc Sci Med 2005; 61: 417-30) is one of several new methods that seek to address pragmatic policy-level questions via broad-based literature reviews. Inspired by Kuhn, meta-narrative review takes a historical and paradigmatic approach to considering different areas of research activity. As an interpretive tool, the approach seeks distinct research traditions, each with its own meta-narrative. We then use these ‘stories of how research unfolded’ as a way of making sense of a diverse literature. Incommensurability between different traditions is seen not as a problem to be lamented or resolved but as a window to higher-order explanations about the nuances of empirical data and what these nuances mean for different applied situations. Having originally developed the meta-narrative method for a study of the diffusion of innovations in healthcare, we are now applying it in a review of the electronic patient record (EPR) in an organizational context. We have collated some 600 papers and books across multiple research traditions including health informatics, information systems research, computer-supported cooperative work (CSCW) and sociology. This very contemporary topic area is raising interesting methodological questions. For example, the EPR literature does not comprise as cleanly delineable traditions for four main reasons: 1. Information and communications technology research is a particularly fast-moving field, so paradigm shifts are relatively common (e.g. the rise of CSCW out of human-computer interaction research). 2. In the electronic age, it is easy for researchers to explore beyond their own discipline and ‘borrow’ theories, ideas and methods from elsewhere. Journal editors may commission overviews from experts in another tradition; authors may explicitly address an audience in another tradition. Research traditions can begin to converge (e.g. papers bringing together CSCW, information systems research and STS). 3. Some researchers are adept ‘boundary spanners’, writing for a number of different academic audiences and adapting their theoretical pedigree to fit (e.g. Marc Berg). 4. Some traditions are characterized not by a single unified paradigm but by active dialogue between competing paradigms (e.g. ‘hard’ versus ‘soft’ perspectives on knowledge management). This work contributes to the STS literature by critically questioning the nature of rigour in secondary research. The EBM movement values ‘Cochrane’ reviews because they meet positivist criteria (e.g. they are rational, objective, replicable, data-led, and transferable across contexts). In contrast, the meta-narrative review is interpretive, reflexive, problem-oriented and work-led, and makes no claim to either replicability or transferability. Rigour is redefined in terms of plausibility, authenticity and usefulness – raising the radical suggestion that the evidence base for key policy decisions can never be set in stone

Nanomechanics of flexoelectric switching

We examine the phenomenon of flexoelectric switching of polarization in ultrathin films of barium titanate induced by a tip of an atomic force microscope (AFM). The spatial distribution of the tip-induced flexoelectricity is computationally modeled both for perpendicular mechanical load (point measurements) and for sliding load (scanning measurements), and compared with experiments. We find that (i) perpendicular load does not lead to stable ferroelectric switching in contrast to the load applied in the sliding contact load regime, due to nontrivial differences between the strain distributions in both regimes: ferroelectric switching for the perpendicular load mode is impaired by a strain gradient inversion layer immediately underneath the AFM tip; while for the sliding load regime, domain inversion is unimpaired within a greater material volume subjected to larger values of the mechanically induced electric field that includes the region behind the sliding tip; (ii) beyond a relatively small value of an applied force, increasing mechanical pressure does not increase the flexoelectric field inside the film, but results instead in a growing volume of the region subjected to such field that aids domain nucleation processes; and (iii) the flexoelectric coefficients of the films are of the order of few nC/m, which is much smaller than for bulk BaTiO3 ceramics, indicating that there is a “flexoelectric size effect” that mirrors the ferroelectric one

Nanomechanics of flexoelectric switching

We examine the phenomenon of flexoelectric switching of polarization in ultrathin films of barium titanate induced by a tip of an atomic force microscope (AFM). The spatial distribution of the tip-induced flexoelectricity is computationally modeled both for perpendicular mechanical load (point measurements) and for sliding load (scanning measurements), and compared with experiments. We find that (i) perpendicular load does not lead to stable ferroelectric switching in contrast to the load applied in the sliding contact load regime, due to nontrivial differences between the strain distributions in both regimes: ferroelectric switching for the perpendicular load mode is impaired by a strain gradient inversion layer immediately underneath the AFM tip; while for the sliding load regime, domain inversion is unimpaired within a greater material volume subjected to larger values of the mechanically induced electric field that includes the region behind the sliding tip; (ii) beyond a relatively small value of an applied force, increasing mechanical pressure does not increase the flexoelectric field inside the film, but results instead in a growing volume of the region subjected to such field that aids domain nucleation processes; and (iii) the flexoelectric coefficients of the films are of the order of few nC/m, which is much smaller than for bulk BaTiO3 ceramics, indicating that there is a “flexoelectric size effect” that mirrors the ferroelectric one

Regional and developmental brain expression patterns of SNAP25 splice variants

SNAP25 is an essential SNARE protein for regulated exocytosis in neuronal cells. Differential splicing of the SNAP25 gene results in the expression of two transcripts, SNAP25a and SNAP25b. These splice variants differ by only 9 amino acids, and studies of their expression to date have been limited to analysis of the corresponding mRNAs. Although these studies have been highly informative, it is possible that factors such as differential turnover of the SNAP25 proteins could complicate interpretations based entirely on mRNA expression profiles