Advancing laboratory medicine in hospitals through health information exchange: a survey of specialist physicians in Canada.

BACKGROUND: Laboratory testing occupies a prominent place in health care. Information technology systems have the potential to empower laboratory experts and to enhance the interpretation of test results in order to better support physicians in their quest for better and safer patient care. This study sought to develop a better understanding of which laboratory information exchange (LIE) systems and features specialist physicians are using in hospital settings to consult their patients' laboratory test results, and what benefit they derive from such use. METHODS: As part of a broader research program on the use of health information exchange systems for laboratory medicine in Quebec, Canada, this study was designed as on online survey. Our sample is composed of 566 specialist physicians working in hospital settings, out of the 1512 physicians who responded to the survey (response rate of 17%). Respondents are representative of the targeted population of specialist physicians in terms of gender, age and hospital location. RESULTS: We first observed that 80% of the surveyed physicians used the province-wide interoperable electronic health records (iEHR) system and 93% used a laboratory results viewer (LRV) to consult laboratory test results and most (72%) use both systems to retrieve lab results. Next, our findings reveal important differences in the capabilities available in each type of system and in the use of these capabilities. Third, there are differences in the nature of the perceived benefits obtained from the use of each of these two systems. Last, the extent of use of an LRV is strongly influenced by the IT artefact itself (i.e., the hospital's LRV available capabilities) while the use of the provincial iEHR system is influenced by its organizational context (i.e. the hospital's size and location). CONCLUSIONS: The main contribution of this study lies in its insights into the role played by context in shaping physicians' choices about which laboratory information exchange systems to adopt and which features to use, and the different perceptions they have about benefits arising from such use. One related implication for practice is that success of LIE initiatives should not be solely assessed with basic usage statistics.

Ceiling effect in EMR system assimilation: a multiple case study in primary care family practices.

BACKGROUND: There has been indisputable growth in adoption of electronic medical record (EMR) systems in the recent years. However, physicians' progress in using these systems has stagnated when measured with maturity scales. While this so-called ceiling effect has been observed and its consequences described in previous studies, there is a paucity of research on the elements that could explain such an outcome. We first suggest that in the context of EMR systems we are in presence of a "tiered ceiling effect" and then we show why such phenomenon occurs. METHODS: We conducted in-depth case studies in three primary care medical practices in Canada where physicians had been using EMR systems for 3 years or more. A total of 37 semi-structured interviews were conducted with key informants: family physicians (about half of the interviews), nurses, secretaries, and administrative managers. Additional information was obtained through notes taken during observations of users interacting with their EMR systems and consultation of relevant documents at each site. We used abductive reasoning to infer explanations of the observed phenomenon by going back and forth between the case data and conceptual insights. RESULTS: Our analysis shows that a ceiling effect has taken place in the three clinics. We identified a set of conditions preventing the users from overcoming the ceiling. In adopting an EMR system, all three clinics essentially sought improved operational efficiency. This had an influence on the criteria used to assess the systems available on the market and eventually led to the adoption of a system that met the specified criteria without being optimal. Later, training sessions focussed on basic functionalities that minimally disturbed physicians' habits while helping their medical practices become more efficient. Satisfied with the outcome of their system use, physicians were likely to ignore more advanced EMR system functionalities. This was because their knowledge about EMR systems came almost exclusively from a single source of information: their EMR system vendors. This knowledge took the form of interpretations of what the innovation was (know-what), with little consideration of the rationales for innovation adoption (know-why) or hands-on strategies for adopting, implementing and assimilating the innovation in the organization (know-how). CONCLUSIONS: This paper provides a holistic view of the technological innovation process in primary care and contends that limited learning, satisficing behaviours and organizational inertia are important factors leading to the ceiling effect frequently experienced in the EMR system assimilation phase.

Impacts of a Large Decentralized Telepathology Network in Canada.

BACKGROUND: Telepathology is a fast growing segment of the telemedicine field. As of yet, no prior research has investigated the impacts of large decentralized telepathology projects on patients, clinicians, and healthcare systems. This study aims to fill this gap. We report a benefits evaluation study of a large decentralized telepathology project deployed in Eastern Quebec, Canada whose main objective is to provide continuous coverage of intraoperative consultations in remote hospitals without pathologists on-site. The project involves 18 hospitals, making it one of the largest telepathology networks in the world. MATERIALS AND METHODS: We conducted 43 semistructured interviews with several telepathology users and hospital managers. Archival data on the impacts of the telepathology project (e.g., number of service disruptions, average time between initial diagnosis and surgery) were also extracted and analyzed. RESULTS: Our findings show that no service disruptions were recorded in hospitals without pathologists following the deployment of telepathology. Surgeons noted that the use of intraoperative consultations enabled by telepathology helped avoid second surgeries and improved accessibility to care services. Telepathology was also perceived by our respondents as having positive impacts on the remote hospitals' ability to retain and recruit surgeons. CONCLUSIONS: The observed benefits should not leave the impression that implementing telepathology is a trivial matter. Indeed, many technical, human, and organizational challenges may be encountered. Telepathology can be highly useful in regional hospitals that do not have a pathologist on-site. More research is needed to investigate the challenges and benefits associated with large decentralized telepathology networks.

Improving performance in medical practices through the extended use of electronic medical record systems: a survey of Canadian family physicians.

BACKGROUND: Numerous calls have been made for greater assimilation of information technology in healthcare organizations in general, and in primary care settings in particular. Considering the levels of IT investment and adoption in primary care medical practices, a deeper understanding is needed of the factors leading to greater performance outcomes from EMR systems in primary care. To address this issue, we developed and tested a research model centered on the concept of Extended EMR Use. METHODS: An online survey was conducted of 331 family physicians in Canadian private medical practices to empirically test seven research hypotheses using a component-based structural equation modeling approach. RESULTS: Five hypotheses were partially or fully supported by our data. Family physicians in our sample used 67% of the clinical and 41% of the communicational functionalities available in their EMR systems, compared to 90% of the administrative features. As expected, extended use was associated with significant improvements in perceived performance benefits. Interestingly, the benefits derived from system use were mainly tied to the clinical support provided by an EMR system. The extent to which physicians were using their EMR systems was influenced by two system design characteristics: functional coverage and ease of use. The more functionalities that are available in an EMR system and the easier they are to use, the greater the potential for exploration, assimilation and appropriation by family physicians. CONCLUSIONS: Our study has contributed to the extant literature by proposing a new concept: Extended EMR Use. In terms of its practical implications, our study reveals that family physicians must use as many of the capabilities supported by their EMR system as possible, especially those which support clinical tasks, if they are to maximize its performance benefits. To ensure extended use of their software, vendors must develop EMR systems that satisfy two important design characteristics: functional coverage and system ease of use.

The effects of a regional telepathology project: a study protocol.

BACKGROUND: Telepathology, which is an emerging form of telemedicine in Canada, is defined as the electronic transmission of pathological images, usually derived from microscopes, from one location to another. There are various applications of telepathology, including case referral for an expert opinion, provision of an emergency service in the absence of a resident pathologist, and education. Until now, there has been relatively little use of telepathology for core diagnostic services in the absence of a local pathologist, but this practice is likely to increase in the future. The Laval University Integrated Health Network is in the process of deploying a telepathology system, primarily to provide an intraoperative frozen section service to small hospitals in sparsely populated areas which are experiencing a severe shortage of on-site pathologists. The telepathology project involves 17 hospitals located in five regions of eastern Quebec, Canada. This paper describes the study protocol that will be used to evaluate the benefits associated with the project. METHODS/DESIGN: A panel of experts was first assembled by Canada Health Infoway to agree on a set of benefits indicators that could be applied to all telepathology projects across Canada. Using the set of indicators as an input, we have developed a three-step study protocol. First, a survey questionnaire will be distributed to appraise the way pathologists, pathology technologists and surgeons perceive the telepathology system and its impacts. Second, a series of semi-structured interviews will be conducted with project leaders and telepathology users at sites that are representative of all the hospitals in the Laval University Integrated Health Network. The overall aim is to better understand the expected and unexpected effects of telepathology on health care professionals and patients as well as on the regional organization and delivery of care services. Finally, a pre-post design using secondary data is proposed to evaluate a wide array of tangible benefits to the patients, the health care providers, the hospitals, and the region as a whole. DISCUSSION: The Laval University Integrated Health Network's telepathology project is expected to yield positive and significant results that are relevant internationally. Our findings will provide valuable information on the nature and extent of benefits associated with telepathology systems intended to provide an intraoperative frozen section service to remote hospitals experiencing a shortage of specialists.

[The Eastern Quebec telepathology network: a real collective project]. / Le réseau de télépathologie de l'Est du Québec - Un véritable projet collectif.

The aim of the Eastern Québec telepathology network is to provide uniform diagnostic telepathology services across a huge geographic region with a low population density. This project is intended to provide surgeons and pathologists with frozen section and second opinion services anywhere and at any time across the entire region, in order to avoid unnecessary patient transfer. The project has been implemented in 21 sites, each equipped with a whole slide scanner, a macroscopy station, a videoconferencing device and a viewer/case management and collaboration solution. Of the 21 sites, 6 are devoid of a pathology laboratory, two have no pathologist and 5 have only one pathologist on site. Signs of improvement of medical care in this region are already apparent since the Eastern Québec telepathology network has been implemented. However, it is important not to underestimate the challenges related to change management in the course of implementation of such a new technology.

Health information technology success and the art of being mindful: preliminary insights from a comparative case study analysis.

BACKGROUND: Information technologies (ITs) represent an important lever for improving performance in health care systems. In recent years, most industrialized countries have made substantial investments in this area. Nevertheless, the sad truth is that far too many of these IT projects have failed. PURPOSE: The primary goals of this study were to explore the notion of mindfulness proposed by E. B. Swanson and N. C. Ramiller (2004) and to assess the extent to which, and how, innovating mindfully influences health IT project success. METHODOLOGY: Two in-depth case studies were conducted in comparable health care organizations that adopted the same clinical information system. Observation, semistructured interviews, informal discussions, and documentation were the primary data collection methods. Data analyses were performed following recognized guidelines. RESULTS: Throughout the unfolding of the two projects, the actions and decisions of key stakeholders reflected different levels of mindfulness. The cross-case comparison was particularly relevant given that project circumstances led to contrasting outcomes. PRACTICE IMPLICATIONS: Taking action and making decisions in light of the particular context of each particular health IT project, that is, innovating mindfully, favor innovation acceptance and positive outcomes, whereas acting and deciding following fads, fashion, or best practices without paying attention to the specifics of the project context, that is, innovating mindlessly, increase the risk of human resistance and limited added value.

Assimilation of Medical Appointment Scheduling Systems and Their Impact on the Accessibility of Primary Care: Mixed Methods Study.

BACKGROUND: The COVID-19 pandemic has prompted the adoption of digital health technologies to maximize the accessibility of medical care in primary care settings. Medical appointment scheduling (MAS) systems are among the most essential technologies. Prior studies on MAS systems have taken either a user-oriented perspective, focusing on perceived outcomes such as patient satisfaction, or a technical perspective, focusing on optimizing medical scheduling algorithms. Less attention has been given to the extent to which family medicine practices have assimilated these systems into their daily operations and achieved impacts. OBJECTIVE: This study aimed to fill this gap and provide answers to the following questions: (1) to what extent have primary care practices assimilated MAS systems into their daily operations? (2) what are the impacts of assimilating MAS systems on the accessibility and availability of primary care? and (3) what are the organizational and managerial factors associated with greater assimilation of MAS systems in family medicine clinics? METHODS: A survey study targeting all family medicine clinics in Quebec, Canada, was conducted. The questionnaire was addressed to the individual responsible for managing medical schedules and appointments at these clinics. Following basic descriptive statistics, component-based structural equation modeling was used to empirically explore the causal paths implied in the conceptual framework. A cluster analysis was also performed to complement the causal analysis. As a final step, 6 experts in MAS systems were interviewed. Qualitative data were then coded and extracted using standard content analysis methods. RESULTS: A total of 70 valid questionnaires were collected and analyzed. A large majority of the surveyed clinics had implemented MAS systems, with an average use of 1 or 2 functionalities, mainly "automated appointment confirmation and reminders" and "online appointment confirmation, modification, or cancellation by the patient." More extensive use of MAS systems appears to contribute to improved availability of medical care in these clinics, notwithstanding the effect of their application of advanced access principles. Also, greater integration of MAS systems into the clinic's electronic medical record system led to more extensive use. Our study further indicated that smaller clinics were less likely to undertake such integration and therefore showed less availability of medical care for their patients. Finally, our findings indicated that those clinics that showed a greater adoption rate and that used the provincial MAS system tended to be the highest-performing ones in terms of accessibility and availability of care. CONCLUSIONS: The main contribution of this study lies in the empirical demonstration that greater integration and assimilation of MAS systems in family medicine clinics lead to greater accessibility and availability of care for their patients and the general population. Valuable insight has also been provided on how to identify the clinics that would benefit most from such digital health solutions.

Improving performance in the ED through laboratory information exchange systems.

BACKGROUND: The accessibility of laboratory test results is crucial to the performance of emergency departments and to the safety of patients. This study aims to develop a better understanding of which laboratory information exchange (LIE) systems emergency care physicians (ECPs) are using to consult their patients' laboratory test results and which benefits they derive from such use. METHODS: A survey of 163 (36%) ECPs in Quebec was conducted in collaboration with the Quebec's Department of Health and Social Services. Descriptive statistics, chi-square tests, cluster analyses, and ANOVAs were conducted. RESULTS: The great majority of respondents indicated that they use several LIE systems including interoperable electronic health record (iEHR) systems, laboratory results viewers (LRVs), and emergency department information systems (EDIS) to consult their patients' laboratory results. Three distinct profiles of LIE users were observed. The extent of LIE usage was found to be primarily determined by the functional design differences between LIE systems available in the EDs. Our findings also indicate that the more widespread LIE usage, the higher the perceived benefits. More specifically, physicians who make extensive use of iEHR systems and LRVs obtain the widest range of benefits in terms of efficiency, quality, and safety of emergency care. CONCLUSIONS: Extensive use of LIE systems allows ECPs to better determine and monitor the health status of their patients, verify their diagnostic assumptions, and apply evidence-based practices in laboratory medicine. But for such benefits to be possible, ECPs must be provided with LIE systems that produce accurate, up-to-date, complete, and easy-to-interpret information.

Laboratory testing in primary care: A systematic review of health IT impacts.

INTRODUCTION: Laboratory testing in primary care is a fundamental process that supports patient management and care. Any breakdown in the process may alter clinical information gathering and decision-making activities and can lead to medical errors and potential adverse outcomes for patients. Various information technologies are being used in primary care with the goal to support the process, maximize patient benefits and reduce medical errors. However, the overall impact of health information technologies on laboratory testing processes has not been evaluated. OBJECTIVES: To synthesize the positive and negative impacts resulting from the use of health information technology in each phase of the laboratory 'total testing process' in primary care. METHODS: We conducted a systematic review. Databases including Medline, PubMed, CINAHL, Web of Science and Google Scholar were searched. Studies eligible for inclusion reported empirical data on: 1) the use of a specific IT system, 2) the impacts of the systems to support the laboratory testing process, and were conducted in 3) primary care settings (including ambulatory care and primary care offices). Our final sample consisted of 22 empirical studies which were mapped to a framework that outlines the phases of the laboratory total testing process, focusing on phases where medical errors may occur. RESULTS: Health information technology systems support several phases of the laboratory testing process, from ordering the test to following-up with patients. This is a growing field of research with most studies focusing on the use of information technology during the final phases of the laboratory total testing process. The findings were largely positive. Positive impacts included easier access to test results by primary care providers, reduced turnaround times, and increased prescribed tests based on best practice guidelines. Negative impacts were reported in several studies: paper-based processes employed in parallel to the electronic process increased the potential for medical errors due to clinicians' cognitive overload; systems deemed not reliable or user-friendly hampered clinicians' performance; and organizational issues arose when results tracking relied on the prescribers' memory. DISCUSSION: The potential of health information technology lies not only in the exchange of health information, but also in knowledge sharing among clinicians. This review has underscored the important role played by cognitive factors, which are critical in the clinician's decision-making, the selection of the most appropriate tests, correct interpretation of the results and efficient interventions. CONCLUSIONS: By providing the right information, at the right time to the right clinician, many IT solutions adequately support the laboratory testing process and help primary care clinicians make better decisions. However, several technological and organizational barriers require more attention to fully support the highly fragmented and error-prone process of laboratory testing.

Knowledge barriers to PACS adoption and implementation in hospitals.

PURPOSE: Drawing on the classical theory of diffusion of innovations advanced by Rogers [E.M. Rogers, Diffusion of Innovations, 4th ed., Free Press, New York, NY, 1995] and on the theory of barriers to innovation [P. Attewell, Technology diffusion and organizational learning: the case of business computing. Organ. Sci. 3 (1992) 1-19; H. Tanriverdi, C.S. Iacono, Knowledge barriers to diffusion of telemedicine. Proceedings of the 20th International Conference on Information Systems, Charlotte, NC, 1999, pp. 39-50; S. Nambisan, Y.-M. Wang, Roadblocks to web technology adoption? Commun. ACM, 42 (1) (1999) 98-101], this study seeks a better understanding of challenges faced in PACS implementations in hospitals and of the strategies required to ensure their success. METHODS: To attain this objective, we describe and analyze the process used to adopt and implement PACS at two Canadian hospitals. RESULTS: Our findings clearly demonstrate the importance of treating any PACS deployment not simply as a rollout of new technology but as a project that will transform the organization. Proponents of these projects must not lose sight of the fact that, even if technological complexity represents a significant issue, it must not garner all the project team's attention. This situation is even more dangerous, inasmuch as the greatest risk to the implementation often lies elsewhere. It would also appear to be crucial to anticipate and address organizational and behavioral challenges from the very first phase of the innovation process, in order to ensure that all participants will be committed to the project. CONCLUSIONS: In order to maximize the likelihood of PACS success, it appears crucial to adopt a proactive implementation strategy, one that takes into consideration all the technical, economic, organizational, and human factors, and does so from the first phase of the innovation process.

Electronic health record usage behaviors in primary care medical practices: A survey of family physicians in Canada.

OBJECTIVE: The importance and potential value of office-based electronic health record (EHR) systems is being recognized internationally. We thus sought to better understand how EHRs are actually being used by family physicians and what they perceive to be the main performance outcomes for themselves and their medical practices. METHODS: We conducted a survey of family physicians practicing in medical practices in Quebec, Canada (n =331). Bivariate and multivariate statistical analyses were conducted to characterize EHR usage behaviors and assess the perceived performance outcomes of these systems. RESULTS: EHR systems "as-used" vary substantively from one family physician to another in terms of the capabilities that are actually mobilized by them. Significant differences between "basic" and "advanced" users were observed in terms of the EHR system's characteristics and perceived performance outcomes. Physicians were also clustered under three profiles that could be clearly distinguished from one another, in terms of the extent to which their performance and their practice's performance was impacted by their EHR usage. Physicians that are "highly impacted" by their EHR system are those who have the longest usage experience and make the most extended use of their system's capabilities. CONCLUSIONS: Our study indicates that only a minority of family physicians in our sample use most of the features available in their EHR system. Consequently, few physicians perceive gaining significant performance improvements from such systems. Future research must identify the factors that motivate primary care physicians to assimilate EHR systems in a more extensive manner.

Simulation of QRST integral maps with a membrane-based computer heart model employing parallel processing.

The simulation of the propagation of electrical activity in a membrane-based realistic-geometry computer model of the ventricles of the human heart, using the governing monodomain reaction-diffusion equation, is described. Each model point is represented by the phase 1 Luo-Rudy membrane model, modified to represent human action potentials. A separate longer duration action potential was used for the M cells found in the ventricular midwall. Cardiac fiber rotation across the ventricular wall was implemented via an analytic equation, resulting in a spatially varying anisotropic conductivity tensor and, consequently, anisotropic propagation. Since the model comprises approximately 12.5 million points, parallel processing on a multiprocessor computer was used to cut down on simulation time. The simulation of normal activation as well as that of ectopic beats is described. The hypothesis that in situ electrotonic coupling in the myocardium can diminish the gradients of action-potential duration across the ventricular wall was also verified in the model simulations. Finally, the sensitivity of QRST integral maps to local alterations in action-potential duration was investigated.

Adoption, use, and impact of e-booking in private medical practices: mixed-methods evaluation of a two-year showcase project in Canada.

BACKGROUND: Managing appointments in private medical practices and ambulatory care settings is a complex process. Various strategies to reduce missed appointments can be implemented. E-booking systems, which allow patients to schedule and manage medical appointments online, represents such a strategy. To better support clinicians seeking to offer an e-booking service to their patients, health authorities in Canada recently invested in a showcase project involving six private medical clinics. OBJECTIVE: The objectives pursued in this study were threefold: (1) to measure adoption and use of the e-booking system in each of the clinics over a 2-year period, (2) to assess patients' perceptions regarding the characteristics and benefits of using the system, and (3) to measure the impact of the e-booking system on the number of missed appointments in each clinic. METHODS: A mixed-methods approach was adopted in this study. We first extracted and analyzed raw data from the e-booking system deployed in each of the medical practices to monitor adoption and use of the system over time and to assess the impact of the system on the number of missed appointments. Second, we conducted a Web-based survey of patients' perceptions in the spring of 2013. RESULTS: The patients and physicians targeted by this showcase project showed a growing interest in the e-booking system as the number of users, time slots made available by physicians, and online appointments grew steadily over time. The great majority of patients said that they appreciated the system mainly because of the benefits they derived from it, namely, scheduling flexibility, time savings, and automated reminders that prevented forgotten appointments. Importantly, our findings suggest that the system's automated reminders help significantly reduce the number of missed appointments. CONCLUSIONS: E-booking systems seem to represent a win-win solution for patients and physicians in private medical practices. We encourage researchers to replicate and extend our work in other primary care settings in order to test the generalizability of our findings.

The Eastern Québec Telepathology Network: a three-year experience of clinical diagnostic services.

BACKGROUND: The Eastern Quebec Telepathology Network (called Réseau de Télépathologie de l'Est du Québec in French) was created to provide uniform diagnostic telepathology services in a huge territory with low population density. We report our first 3-year experience. METHODS: The network was funded equally by the Québec ministry of Health and Canada Health Infoway, a federal telehealth funding agency. The coverage includes intraoperative consultations (IOC), expert opinions, urgent analyses and supervision of macroscopic description. The deployment of the equipment and software started in 2010 and clinical activities began in January 2011. This network comprises 24 hospitals providing oncologic surgery, of which 7 have no pathology laboratory and 4 have a pathology laboratory but no pathologist. The real-time gross evaluation during IOC was performed using a macroscopy station and the sample selection was performed distantly by a technician, a pathology assistant or the surgeon under on-site pathologist supervision. Slides were scanned into whole-slide images (WSI). RESULTS: As per March 2014, 7,440 slides had been scanned for primary/urgent diagnosis; 1,329 for IOC cases and 2,308 for expert opinions. A 98% concordance rate was found for IOC compared to paraffin material and the average turnaround time was 20 minutes. Expert opinion reports were signed out within 24 hours in 68% of cases and within 72 hours in 85%. A recent multi-method evaluation study of the Network demonstrated that, thanks to telepathology: 1. interruption of IOC service was prevented in hospitals with no pathologist on site; 2. two-stage surgeries and patients transfers were prevented according to surgeons and pathologists; 3. retention and recruitment of surgeons in remote hospitals were facilitated; and 4. professional isolation among pathologists working alone was reduced. This study also demonstrated that wider adoption of telepathology would require technological improvement and that the sustainability of the network requires better coordination and the development of a supra-regional pathology organisation. CONCLUSION: The Eastern Quebec Telepathology Network allowed the maintenance of rapid and high quality pathology services in more than 20 sites disseminated on a huge territory. A second phase is underway to expand telepathology to other regions across the province.

Barriers to organizational adoption of EMR systems in family physician practices: a mixed-methods study in Canada.

BACKGROUND: EMR system can provide three main types of benefits: it can solve the logistical organization problems associated with paper systems; it can improve the quality of professionals' clinical decisions; and it can improve physicians' return on their practices by reducing the cost of managing clinical information. According to the 2012 Commonwealth Fund International Health Policy Survey, Canada ranked 10th out of 11 countries in terms of family physicians' adoption of EMR systems. Our main purpose is to investigate the reasons why so many primary care medical practices in this country have not decided to invest in these systems yet. METHODS: To achieve our main objective, a mixed-methods study was performed. We first conducted a Delphi study with a panel of 21 experts made up of general practitioners with extensive professional experience and a very good understanding of the issues surrounding the introduction of health IT in private medical practices. As a second step, we collected and analyzed data from a large questionnaire survey of family physicians working in medical practices without EMR systems (n = 431). RESULTS: The Delphi study reveals that private medical practices are hindered by four types of barriers when faced with the initial decision to invest in an EMR system, namely, behavioral, cognitive or knowledge-based, economic, and technological. Survey findings then indicate that the key challenges preventing private medical practices from investing in an EMR system are mainly related to economic and knowledge barriers. Surprisingly, we also found a cluster of medical practices which, although they have not invested in an EMR system, perceive no such barriers to adoption. CONCLUSIONS: A thorough understanding of the barriers faced by family physician practices in adopting an EMR system would help governments and other key stakeholders target policies and measures in support of medical practices. The "one size fits all" approach to such policies and measures is clearly inappropriate, given this study's findings that many medical practices face practically no barriers to EMR adoption, and that others differ markedly as to the type of barriers faced, be they mostly "soft" such as knowledge barriers or "hard" such as economic barriers.

A mechanical force contributes to the "osmotic swelling" of brush-border membrane vesicles.

Brush-border membrane vesicles and an osmotic swelling assay have been used extensively to monitor the pore-forming activity of Bacillus thuringiensis toxins. After a hypertonic shock, Manduca sexta midgut brush-border membrane vesicles shrink rapidly and reswell partially to a volume that depends on membrane permeability and toxin concentration rather than regaining their original volume as expected from theoretical models. Because efflux of buffer from the vesicles, as they shrink, could contribute to this phenomenon, vesicles were mixed with a hypertonic solution of the buffer with which they were loaded. Under these conditions, they are not expected to reswell, since the same solute is present on both sides of the membrane. Nevertheless, with several buffers, vesicles reswelled readily, an observation that demonstrates the involvement of an additional restoration force. Reswelling also occurred when, in the absence of toxin, the buffers were replaced by glucose, a solute that diffuses readily across the membrane, but did not occur with rat liver microsomes, despite their permeability to glucose. Unexpected swelling was also observed with rabbit jejunum brush-border membrane vesicles, suggesting that the cytoskeleton, present in brush-border membrane vesicles but absent from microsomes, could be responsible for the restoration force.