Clinical decision support system for point of care use--ontology-driven design and software implementation.

OBJECTIVES: The objective of this research was to design a clinical decision support system (CDSS) that supports heterogeneous clinical decision problems and runs on multiple computing platforms. Meeting this objective required a novel design to create an extendable and easy to maintain clinical CDSS for point of care support. The proposed solution was evaluated in a proof of concept implementation. METHODS: Based on our earlier research with the design of a mobile CDSS for emergency triage we used ontology-driven design to represent essential components of a CDSS. Models of clinical decision problems were derived from the ontology and they were processed into executable applications during runtime. This allowed scaling applications' functionality to the capabilities of computing platforms. A prototype of the system was implemented using the extended client-server architecture and Web services to distribute the functions of the system and to make it operational in limited connectivity conditions. RESULTS: The proposed design provided a common framework that facilitated development of diversified clinical applications running seamlessly on a variety of computing platforms. It was prototyped for two clinical decision problems and settings (triage of acute pain in the emergency department and postoperative management of radical prostatectomy on the hospital ward) and implemented on two computing platforms--desktop and handheld computers. CONCLUSIONS: The requirement of the CDSS heterogeneity was satisfied with ontology-driven design. Processing of application models described with the help of ontological models allowed having a complex system running on multiple computing platforms with different capabilities. Finally, separation of models and runtime components contributed to improved extensibility and maintainability of the system.

Design and development of a mobile system for supporting emergency triage.

OBJECTIVES: Our objective was to design and develop a mobile clinical decision support system for emergency triage of different acute pain presentations. The system should interact with existing hospital information systems, run on mobile computing devices (handheld computers) and be suitable for operation in weak-connectivity conditions (with unstable connections between mobile clients and a server). METHODS: The MET (Mobile Emergency Triage) system was designed following an extended client-server architecture. The client component, responsible for triage decision support, is built as a knowledge-based system, with domain ontology separated from generic problem solving methods and used for the automatic creation of a user interface. RESULTS: The MET system is well suited for operation in the Emergency Department of a hospital. The system's external interactions are managed by the server, while the MET clients, running on handheld computers are used by clinicians for collecting clinical data and supporting triage at the bedside. The functionality of the MET client is distributed into specialized modules, responsible for triaging specific types of acute pain presentations. The modules are stored on the server, and on request they can be transferred and executed on the mobile clients. The modular design provides for easy extension of the system's functionality. A clinical trial of the MET system validated the appropriateness of the system's design, and proved the usefulness and acceptance of the system in clinical practice. CONCLUSIONS: The MET system captures the necessary hospital data, allows for entry of patient information, and provides triage support. By operating on handheld computers, it fits into the regular emergency department workflow without introducing any hindrances or disruptions. It supports triage anytime and anywhere, directly at the point of care, and also can be used as an electronic patient chart, facilitating structured data collection.

Redefining emergency medicine procedures: Canadian competence and frequency survey.

OBJECTIVE: To redefine the Royal College of Physicians and Surgeons (RCPS) procedural skills list for Canadian emergency medicine (EM) residents through a national survey of EM specialists to determine procedural performance frequency and self-assessment of competence. METHODS: The survey instrument was developed in three phases: 1) an EM program directors survey identified inappropriate or dated procedures, endorsing 127 skills; 2) a search of EM literature added 98 skills; and 3) an expert panel designed the survey instrument and finalized a list of 150 skills. The survey instrument measured the frequency of procedure performance or supervision, self-reported competence (yes/no), and endorsement of one of four training levels for each skill: undergraduate (UG), postgraduate (PG), knowledge only, or unnecessary (i.e., too infrequently performed to maintain competence). RESULTS: All 289 Canadian EM specialists were surveyed by mail; 231 (80%) responded, 221 completed surveys, and 10 were inactive. More than 60% reported competence in 125 (83%) procedures, and 55 procedures were performed at least three times a year. The mean competence score was 121 (SD +/- 17.7, median = 122) procedures. Competence score correlation with patient volume was r = 0.16 (p = 0.02) and with hours worked was r = 0.19 (p = 0.01). Competence score was not associated with year or route (residency vs grandfather) of certification. Each procedure was assigned to a training level using response consensus and decision rules (UG: 1%; PG: 82%; unnecessary: 17%). CONCLUSIONS: A survey of EM clinicians reporting competence and frequency of skill performance defined 127 procedural skills appropriate for Canadian RCPS postgraduate training and EM certification.

Tissue adhesives for traumatic lacerations in children and adults.

BACKGROUND: Tissue adhesives have been used for many years to close simple lacerations as an alternative to standard wound closure (sutures, staples, adhesive strips). They offer many potential advantages over standard wound closure, including ease of use, decrease in pain and time to apply, as well as not requiring a follow-up visit for removal. Many studies have compared tissue adhesives and standard wound closure to determine the cosmetic outcome as well as these other secondary outcomes in their respective study populations. However, due to the wide variation in study parameters, there are no generalisable, definitive answers about the effectiveness of tissue adhesives. No study has been adequately powered to assess differences in complications, which are rare. OBJECTIVES: To summarize the best available evidence for the effect of tissue adhesives in the management of traumatic lacerations in children and adults. SEARCH STRATEGY: We searched the Cochrane Controlled Trials Register (CD ROM 2001 Issue 4), the Cochrane Wounds Group Specialized Trials Register (Nov 2001), MEDLINE (1966 to Oct 1, 2001), and EMBASE (1988 to Sept 1, 2001) for relevant randomised controlled trials (RCTs). We also searched the citations of selected studies, and we contacted relevant authors and manufacturers of tissue adhesives to inquire about other published and unpublished trials. SELECTION CRITERIA: We included RCTs comparing tissue adhesives versus standard wound closure or tissue adhesive versus tissue adhesive for acute, linear, low tension, traumatic lacerations in an emergency or primary care setting. Trials evaluating tissue adhesives for surgical incisions or other types of wounds were not considered. DATA COLLECTION AND ANALYSIS: Data from eligible studies were extracted by one reviewer and checked for accuracy by a second reviewer. Two reviewers independently assessed masked copies for quality. Outcomes of cosmesis (subgroups of age, wound location and need for deep sutures), pain, procedure time, ease of use and complications were analysed separately for two comparisons: 1) tissue adhesive versus standard wound care; and 2) tissue adhesive versus tissue adhesive. MAIN RESULTS: Eight studies compared a tissue adhesive with standard wound care. No significant difference was found for cosmesis at any of the time points examined, using either Cosmetic Visual Analogue Scale (CVAS) or Wound Evaluation Score (WES). Data were only available for subgroup analysis for age; no significant differences were found. Pain scores (Parent VAS WMD -15.7 mm; 95% CI -21.9, -9.5) and procedure time (WMD -5.6 minutes; 95% CI -8.2, -3.1) significantly favoured tissue adhesives. No studies reported on ease of use. Small but statistically significant risk differences were found for dehiscence (favouring standard wound care NNH 25 95% CI 14, 100) and erythema (favouring tissue adhesive NNH 8 95% CI 4, 100). Other complications were not significantly different between treatment groups. Only one study was identified that compared two tissue adhesives (butylcyanoacrylate (Histoacryl TM) versus octylcyanoacrylate (Dermabond TM)) for pediatric facial lacerations. No significant difference was found for cosmesis using CVAS at 1-3 months, or using WES at 5-14 days and 1-3 months. Similarly, no significant difference was found in pain, procedure time or complications. Results for ease of use were incomplete as reported. REVIEWER'S CONCLUSIONS: Tissue adhesives are an acceptable alternative to standard wound closure for repairing simple traumatic lacerations. There is no significant difference in cosmetic outcome between tissue adhesives and standard wound closure, or between different tissue adhesives. They offer the benefit of decreased procedure time and less pain, compared to standard wound closure. A small but statistically significant increased rate of dehiscence with tissue adhesives must be considered when choosing the closure method (NNH 25).

Learning the preferences of physicians for the organization of result lists of medical evidence articles.

BACKGROUND: Online medical knowledge repositories such as MEDLINE and The Cochrane Library are increasingly used by physicians to retrieve articles to aid with clinical decision making. The prevailing approach for organizing retrieved articles is in the form of a rank-ordered list, with the assumption that the higher an article is presented on a list, the more relevant it is. OBJECTIVES: Despite this common list-based organization, it is seldom studied how physicians perceive the association between the relevance of articles and the order in which articles are presented. In this paper we describe a case study that captured physician preferences for 3-element lists of medical articles in order to learn how to organize medical knowledge for decision-making. METHODS: Comprehensive relevance evaluations were developed to represent 3-element lists of hypothetical articles that may be retrieved from an online medical knowledge source such as MEDLINE or The Cochrane Library. Comprehensive relevance evaluations asses not only an article's relevance for a query, but also whether it has been placed on the correct list position. In other words an article may be relevant and correctly placed on a result list (e.g. the most relevant article appears first in the result list), an article may be relevant for a query but placed on an incorrect list position (e.g. the most relevant article appears second in a result list), or an article may be irrelevant for a query yet still appear in the result list. The relevance evaluations were presented to six senior physicians who were asked to express their preferences for an article's relevance and its position on a list by pairwise comparisons representing different combinations of 3-element lists. The elicited preferences were assessed using a novel GRIP (Generalized Regression with Intensities of Preference) method and represented as an additive value function. Value functions were derived for individual physicians as well as the group of physicians. RESULTS: The results show that physicians assign significant value to the 1st position on a list and they expect that the most relevant article is presented first. Whilst physicians still prefer obtaining a correctly placed article on position 2, they are also quite satisfied with misplaced relevant article. Low consideration of the 3rd position was uniformly confirmed. CONCLUSIONS: Our findings confirm the importance of placing the most relevant article on the 1st position on a list and the importance paid to position on a list significantly diminishes after the 2nd position. The derived value functions may be used by developers of clinical decision support applications to decide how best to organize medical knowledge for decision making and to create personalized evaluation measures that can augment typical measures used to evaluate information retrieval systems.

Comparing predictions made by a prediction model, clinical score, and physicians: pediatric asthma exacerbations in the emergency department.

BACKGROUND: Asthma exacerbations are one of the most common medical reasons for children to be brought to the hospital emergency department (ED). Various prediction models have been proposed to support diagnosis of exacerbations and evaluation of their severity. OBJECTIVES: First, to evaluate prediction models constructed from data using machine learning techniques and to select the best performing model. Second, to compare predictions from the selected model with predictions from the Pediatric Respiratory Assessment Measure (PRAM) score, and predictions made by ED physicians. DESIGN: A two-phase study conducted in the ED of an academic pediatric hospital. In phase 1 data collected prospectively using paper forms was used to construct and evaluate five prediction models, and the best performing model was selected. In phase 2 data collected prospectively using a mobile system was used to compare the predictions of the selected prediction model with those from PRAM and ED physicians. MEASUREMENTS: Area under the receiver operating characteristic curve and accuracy in phase 1; accuracy, sensitivity, specificity, positive and negative predictive values in phase 2. RESULTS: In phase 1 prediction models were derived from a data set of 240 patients and evaluated using 10-fold cross validation. A naive Bayes (NB) model demonstrated the best performance and it was selected for phase 2. Evaluation in phase 2 was conducted on data from 82 patients. Predictions made by the NB model were less accurate than the PRAM score and physicians (accuracy of 70.7%, 73.2% and 78.0% respectively), however, according to McNemar's test it is not possible to conclude that the differences between predictions are statistically significant. CONCLUSION: Both the PRAM score and the NB model were less accurate than physicians. The NB model can handle incomplete patient data and as such may complement the PRAM score. However, it requires further research to improve its accuracy.

A task-based support architecture for developing point-of-care clinical decision support systems for the emergency department.

OBJECTIVES: The purpose of this study was to create a task-based support architecture for developing clinical decision support systems (CDSSs) that assist physicians in making decisions at the point-of-care in the emergency department (ED). The backbone of the proposed architecture was established by a task-based emergency workflow model for a patient-physician encounter. METHODS: The architecture was designed according to an agent-oriented paradigm. Specifically, we used the O-MaSE (Organization-based Multi-agent System Engineering) method that allows for iterative translation of functional requirements into architectural components (e.g., agents). The agent-oriented paradigm was extended with ontology-driven design to implement ontological models representing knowledge required by specific agents to operate. RESULTS: The task-based architecture allows for the creation of a CDSS that is aligned with the task-based emergency workflow model. It facilitates decoupling of executable components (agents) from embedded domain knowledge (ontological models), thus supporting their interoperability, sharing, and reuse. The generic architecture was implemented as a pilot system, MET3-AE--a CDSS to help with the management of pediatric asthma exacerbation in the ED. The system was evaluated in a hospital ED. CONCLUSIONS: The architecture allows for the creation of a CDSS that integrates support for all tasks from the task-based emergency workflow model, and interacts with hospital information systems. Proposed architecture also allows for reusing and sharing system components and knowledge across disease-specific CDSSs.

Changes in red cell transfusion practice among adult trauma victims.

BACKGROUND: Recent attention concerning the adverse outcomes of blood transfusion has resulted in decreased blood product usage for nonemergency care. We hypothesized that there has also been a decrease in blood product use in the management of seriously injured adults. METHODS: A retrospective review of institutional database records was conducted at a regional trauma center for adults admitted during 1991, 1993, and 1995. Data was analyzed for trends in amount, type, and timing of blood product use. RESULTS: A total of 1,738 patients were assessed, with 1,605 meeting inclusion. The three patient groups were similar, including injury severity (overall mean Injury Severity Score of 23.6), mechanism (88% blunt), and survival (87%). In 1991, 54% of the patients were transfused a total of 2,341 units of packed red blood cells (mean 4.67 units/pt treated) versus 42% of patients in 1995 (p < 0.0001) who received 2,018 packed red blood cells (mean 3.57 units/patient treated, p = 0.05). A significantly higher proportion of units was transfused in the first 24 hours of care in 1995 (64%) compared with 1991 (21%, p < 0.0001). A reduction in the use of universal donor type-O blood use was also found (1.21 vs. 0.65 units/patient transfused, p < 0.0001). Despite similar admission hemoglobin concentrations (124.1 vs. 125.3, not significant), significant reductions were found in the average 24-hour (109.2 vs. 103.8, p < 0.001), lowest (96.5 vs 92.1, p < 0.01) and discharge (115.8 vs. 110.5, p < 0.001) concentrations. CONCLUSIONS: Between 1991 and 1995 there have been significant reductions in both the number of trauma patients receiving blood products and the total number of units transfused. These findings may reflect lower or abandoned hemoglobin transfusion triggers and increased awareness of complications related to transfusion.