Development and initial validation of an instrument to measure physicians' use of, knowledge about, and attitudes toward computers.

UNLABELLED: This paper describes details of four scales of a questionnaire-- "Computers in Medical Care"--measuring attributes of computer use, self-reported computer knowledge, computer feature demand, and computer optimism of academic physicians. The reliability (i.e., precision, or degree to which the scale's result is reproducible) and validity (i.e., accuracy, or degree to which the scale actually measures what it is supposed to measure) of each scale were examined by analysis of the responses of 771 full-time academic physicians across four departments at five academic medical centers in the United States. The objectives of this paper were to define the psychometric properties of the scales as the basis for a future demonstration study and, pending the results of further validity studies, to provide the questionnaire and scales to the medical informatics community as a tool for measuring the attitudes of health care providers. METHODOLOGY: The dimensionality of each scale and degree of association of each item with the attribute of interest were determined by principal components factor analysis with orthogonal varimax rotation. Weakly associated items (factor loading < .40) were deleted. The reliability of each resultant scale was computed using Cronbach's alpha coefficient. Content validity was addressed during scale construction; construct validity was examined through factor analysis and by correlational analyses. RESULTS: Attributes of computer use, computer knowledge, and computer optimism were unidimensional, with the corresponding scales having reliabilities of .79, .91, and .86, respectively. The computer-feature demand attribute differentiated into two dimensions: the first reflecting demand for high-level functionality with reliability of .81 and the second demand for usability with reliability of .69. There were significant positive correlations between computer use, computer knowledge, and computer optimism scale scores and respondents' hands-on computer use, computer training, and self-reported computer sophistication. In addition, items posited on the computer knowledge scale to be more difficult generated significantly lower scores. CONCLUSION: The four scales of the questionnaire appear to measure with adequate reliability five attributes of academic physicians' attitudes toward computers in medical care: computer use, self-reported computer knowledge, demand for computer functionality, demand for computer usability, and computer optimism. Results of initial validity studies are positive, but further validation of the scales is needed. The URL of a downloadable HTML copy of the questionnaire is provided.

MedWeaver: integrating decision support, literature searching, and Web exploration using the UMLS Metathesaurus.

Integrating functions from disparate and widely-distributed information systems has been an interest of the medical informatics community for some time. Barriers to progress have included the lack of network-accessible information sources, inadequate methods for inter-system messaging, and lack of vocabulary translation services. With the advent of the World Wide Web (WWW) and the evolution of the National Library of Medicine's Unified Medical Language System (UMLS), it is now possible to develop applications that integrate functions from diverse, distributed systems. In this paper we describe one such system, MedWeaver, a WWW application that integrates functions from a decision support application (DXplain), a literature searching system (WebMedline), and a clinical Web searching system (CliniWeb) using the UMLS Metathesaurus for vocabulary translation. This system demonstrates how application developers can design systems around anticipated clinical information needs and then draw together the needed content and functionality from diverse sources.

A continuous-speech interface to a decision support system: I. Techniques to accommodate for misrecognized input.

OBJECTIVE: Develop a continuous-speech interface that allows flexible input of clinical findings into a medical diagnostic application. DESIGN: The authors' program allows users to enter clinical findings using their own vernacular. It displays from the diagnostic program's controlled vocabulary a list of terms that most closely matches the input, and allows the user to select the single best term. The interface program includes two components: a speech-recognition component that converts utterances into text strings, and a language-processing component that matches recognized text strings with controlled-vocabulary terms. The speech-recognition component is composed of commercially available speech-recognition hardware and software, and developer-created grammars, which specify the language to be recognized. The language-processing component is composed of a translator, which extracts a canonical form from both recognized text strings and controlled-vocabulary terms, and a matcher, which measures the similarity between the two canonical forms. RESULTS: The authors discovered that grammars constructed by a physician, who could anticipate how users might speak findings, supported speech recognition better than did grammars constructed programmatically from the controlled vocabulary. However, this programmatic method of grammar construction was more time efficient and better supported long-term maintenance of the grammars. The authors also found that language-processing techniques recovered some of the information lost due to speech misrecognition, but were dependent on the completeness of supporting synonym dictionaries. CONCLUSIONS: The authors' program demonstrated the feasibility of using continuous speech to enter findings into a medical application. However, improvements in speech-recognition technology and language-processing techniques are needed before natural continuous speech becomes an acceptable input modality for clinical applications.

A continuous-speech interface to a decision support system: II. An evaluation using a Wizard-of-Oz experimental paradigm.

OBJECTIVE: Evaluate the performance of a continuous-speech interface to a decision support system. DESIGN: The authors performed a prospective evaluation of a speech interface that matches unconstrained utterances of physicians with controlled-vocabulary terms from Quick Medical Reference (QMR). The performance of the speech interface was assessed in two stages: in the real-time experiment, physician subjects viewed audiovisual stimuli intended to evoke clinical findings, spoke a description of each finding into the speech interface, and then chose from a list generated by the interface the QMR term that most closely matched the finding. Subjects believed that the speech recognizer decoded their utterances; in reality, a hidden experimenter typed utterances into the interface (Wizard-of-Oz experimental design). Later, the authors replayed the same utterances through the speech recognizer and measured how accurately utterances matched with appropriate QMR terms using the results of the real-time experiment as the "gold standard." MEASUREMENTS: The authors measured how accurately the speech-recognition system converted input utterances to text strings (recognition accuracy) and how accurately the speech interface matched input utterances to appropriate QMR terms (semantic accuracy). RESULTS: Overall recognition accuracy was less than 50%. However, using language-processing techniques that match keywords in recognized utterances to keywords in QMR terms, the semantic accuracy of the system was 81%. CONCLUSIONS: Reasonable semantic accuracy was attained when language-processing techniques were used to accommodate for speech misrecognition. In addition, the Wizard-of-Oz experimental design offered many advantages for this evaluation. The authors believe that this technique may be useful to future evaluators of speech-input systems.

A model of clinical query management that supports integration of biomedical information over the World Wide Web.

A model of clinical query management is described that supports the integration of various types of biomedical information and the delivery of that information through a common interface. The model extends the architecture of the World Wide Web to include a Common Gateway Interface (CGI) mediator, which takes in user queries, performs syntactic and semantic processing to transform the input to a canonical form, selects the appropriate information sources to answer the query, translates the canonical query statement into a query of each information resource, queries the chosen information sources in parallel, and controls the analysis and display of results. We describe WebMedline, a CGI mediator that implements portions of this model, and discuss the benefits and limitations of this approach.

Academic physicians' assessment of the effects of computers on health care.

We assessed the attitudes of academic physicians towards computers in health care at two academic medical centers that are in the early stages of clinical information-system deployment. We distributed a 4-page questionnaire to 470 subjects, and a total of 272 physicians (58%) responded. Our results show that respondents use computers frequently, primarily to perform academic-oriented tasks as opposed to clinical tasks. Overall, respondents viewed computers as being slightly beneficial to health care. They perceive self-education and access to up-to-date information as the most beneficial aspects of computers and are most concerned about privacy issues and the effect of computers on the doctor-patient relationship. Physicians with prior computer training and greater knowledge of informatics concepts had more favorable attitudes towards computers in health care. We suggest that negative attitudes towards computers can be addressed by careful system design as well as targeted educational activities.

Office-based interventions to improve delivery of cancer prevention services by primary care physicians.

Physician forgetfulness, patient refusal, and practice logistical difficulties are among the major reasons that physicians perform cancer prevention activities less frequently than recommended by established guidelines. To improve delivery of prevention services, office system interventions of several types have been developed and tested. These include approaches aimed at patients during the medical encounter (in-reach) and outside the medical setting (outreach). In-reach interventions include medical record checklists and flow sheets, stickers and alerts, audit with feedback, nurse-initiated reminders, and computer-generated reminders, including ones generated by mainframe and microcomputer systems. In-reach interventions are directed at patients alone, at physicians alone, at patients and physicians simultaneously, or at office staff. Outreach reminder interventions include reminder postcards, letters, telephone calls, and questionnaires. Outreach reminders are directed at patients alone. The authors review the literature supporting the efficacy of such office systems. The analysis suggests that office systems are effective strategies in promoting cancer prevention activities.

Pulmonary artery balloon counterpulsation: safe after peripheral placement.

Pulmonary artery balloon counterpulsation is a promising experimental technique for treatment of right ventricular failure. However, clinical application has been limited in that the only device presently available (the large-volume intraaortic balloon) must be placed within a synthetic graft. Because a balloon with a smaller volume (which could be placed through a peripheral vein and be contained entirely within the pulmonary artery) would make the technique feasible on a wider scale, we tested an 8-mL pulmonary artery balloon placed through the femoral vein in 12 dogs. Two groups of animals were compared. One group had the pulmonary artery balloon in place but not counterpulsating; the other had the pulmonary artery balloon in place and counterpulsating. Each group was studied for 12 hours. A variety of hemodynamic parameters were measured. Effective diastolic augmentation and systolic unloading were noted in all 6 dogs that underwent counterpulsation (5.0 +/- 1.1 mm Hg of diastolic augmentation and 9.5 +/- 1.6 mm Hg of systolic unloading). Pulmonary function, as measured by arterial blood gas sampling and pulmonary vascular resistance, was not impaired. Examination of the heart and lungs showed no detrimental pathologic effects of pulmonary artery balloon counterpulsation. Placement of the balloon through a peripheral vein with a guidewire was easy and uncomplicated. We conclude that pulmonary artery balloon counterpulsation is safe over an extended period of 12 hours in the canine model and that diastolic augmentation and systolic unloading can be produced.

Design and evaluation of multimedia stimuli to evoke clinical concepts.

Continuous speech recognition systems have the potential to facilitate clinical data entry, but evaluating them rigorously is difficult. We describe a tool to aid evaluators of such systems. The tool is a HyperCard stack with stimuli consisting of pictures, sounds and the minimum of words to evoke 20 QMR physical findings. Despite using up to four different stimuli to communicate each finding and piloting the material on six subjects, eight test subjects made a total of 66 errors (42%) in interpreting the 20 sets of stimuli, of which 22 errors (14%) were serious. These results are relevant to those designing interfaces for decision-support, tutorial and student testing systems.

Potentiation or diminution of discrete motor unconditioned responses (rabbit eyeblink) to an aversive pavlovian unconditioned stimulus by two associative processes: conditioned fear and a conditioned diminution of unconditioned stimulus processing.

In two experiments using the rabbit conditioned eyeblink preparation, the conditions under which a Pavlovian conditioned stimulus (CS) potentiates or diminishes the unconditioned response (UR) were examined. The results indicated that, after discrimination training (CS+ vs. CS-), the CS+ diminished UR amplitude at the training interstimulus interval (ISI). When CS+ trials were segregated into trials on which a conditioned response (CR) did or did not occur, the CS+ diminished the UR when it elicited a CR, but not when a CR failed to occur. When the CS-unconditioned stimulus (US) interval was lengthened to 10 s, the CS+ reliably potentiated the eyeblink UR on CR trials but did not potentiate responding on trials on which a CR was absent. The results are discussed in terms of the modulatory effects and temporal properties of conditioned fear and an associatively produced decrement in US processing.

The Cancer Prevention Reminder System.

The Cancer Prevention Reminder System is a computer-based system designed to increase the delivery of periodic health maintenance procedures. The program provides printed reminders that identify patients' overdue procedures, prints summary reports of the percentage of patients who are eligible and overdue for a procedure, and prints mailing labels for patients. We performed a randomized, controlled trial in which the effects of computer-based reminders were compared with those of two other interventions among residents in a university-based group practice.

Neuropsychiatric complications of AIDS: a literature review.

Acquired immune deficiency syndrome (AIDS) has become a major public health problem with over 12,000 cases and 6,000 deaths reported to date. Although there has been an explosion of knowledge in the virology, immunology and pathology of AIDS, relatively little has been written on the neuropsychiatric aspects. This report reviews the existing literature on the neuropsychiatric complications of AIDS. As many as 40 percent of patients with AIDS have neurologic complications at some point in their illness. These complications include either focal deficits attributable to opportunistic organisms infecting the CNS or diffuse encephalopathy caused by viral infection or lymphoma infiltration. Psychiatric complications include major depression, adjustment disorder with depressed mood, and organic brain syndrome with affective, delusional or demented features. Inpatient and consulting psychiatrists must be alert to these complications of AIDS so as to make accurate diagnoses and deliver appropriate therapy. Further studies, integrating both psychiatric and neurologic perspectives, are needed to better elucidate the neuropsychiatric complications of AIDS and help plan appropriate therapeutic interventions.

Amygdala kindling after ligation of the middle cerebral artery in the rat.

Cerebral infarcts were produced in rats by ligation of the right or left middle cerebral artery. A significant increase in seizure threshold and in the number of days required to develop kindled seizures was found in rats stimulated in the amygdala contralateral to the infarct. However, no significant changes in threshold or kindling rates were found in animals kindled ipsilateral to the ligation. These results were found to be independent of whether the infarct was in the right or left cerebral cortex. These data suggest that contralateral frontoparietal cerebral infarct may have inhibitory influences on seizures originating from the amygdala.