RESUMO
BACKGROUND: Health research apps often do not focus on usability as a design priority. This is problematic when the population of interest is disproportionately underrepresented as users of mobile apps, especially observed with aging older adults (> = 75). Challenges with the adoption of health information technology (HIT) among this group are exacerbated by poor design and user interface/experience (UI/UX) choices. This protocol describes the testing and evaluation process of one HIT app for the family-based collaboration platform InfoSAGE. METHODS: We aim to recruit twenty subjects from both informal family-caregivers and aging older adults to examine the usability of the InfoSAGE mobile medication manager. Participants will be audio and visually recorded, in addition to the use of screen capture recordings, while 'thinking aloud' as they complete eight common use-case scenarios. Multiple independent reviewers will code video and audio recordings for thematic analysis and use problems will be evaluated. Success and failure of each scenario will be determined by completion of sub-events. Time-to-complete analysis will be used to ascertain the learning curve associated with the app. DISCUSSION: Frequently observed problem areas will be used as the basis of further evolution of the app, and will further inform generalized recommendations for the design of HIT apps for research and public use. This study aims to improve the model of development for dual user populations with dissimilar technological literacy to improve retention and use. Results of this study will form the foundation of a design framework for mobile health apps.
Assuntos
Cuidadores , Conduta do Tratamento Medicamentoso , Aplicativos Móveis , Telemedicina , Idoso , Humanos , Informática Médica , Telemedicina/métodosRESUMO
Endochondral bone formation is a highly orchestrated process involving coordination among cell-cell, cell-matrix and growth factor signaling that eventually results in the production of mineralized bone from a cartilage template. Chondrogenic and osteogenic differentiation occur in sequence during this process, and the temporospatial patterning clearly requires the activities of heparin binding growth factors and their receptors. Heparanase (HPSE) plays a role in osteogenesis, but the mechanism by which it does so is incompletely understood. We used a combination of ex vivo and in vitro approaches and a well described HPSE inhibitor, PI-88 to study HPSE in endochondral bone formation. In situ hybridization and immunolocalization with HPSE antibodies revealed that HPSE is expressed in the peri-chondrium, peri-osteum, and at the chondro-osseous junction, all sites of key signaling events and tissue morphogenesis. Transcripts encoding Hpse also were observed in the pre-hypertrophic zone. Addition of PI-88 to metatarsals in organ culture reduced growth and suggested that HPSE activity aids the transition from chondrogenic to osteogenic processes in growth of long bones. To study this, we used high density cultures of ATDC5 pre-chondrogenic cells grown under conditions favoring chondrogenesis or osteogenesis. Under chondrogenic conditions, HPSE/Hpse was expressed at high levels during the mid-culture period, at the onset of terminal chondrogenesis. PI-88 addition reduced chondrogenesis and accelerated osteogenesis, including a dramatic up-regulation of osteocalcin levels. In normal growth medium, addition of PI-88 reduced migration of ATDC-5 cells, suggesting that HPSE facilitates cartilage replacement by bone at the chondro-osseous junction by removing the HS component of proteoglycans, such as perlecan/HSPG2, that otherwise prevent osteogenic cells from remodeling hypertrophic cartilage.
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Condrócitos/metabolismo , Regulação Enzimológica da Expressão Gênica , Glucuronidase/genética , Osteogênese/genética , Animais , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Movimento Celular/fisiologia , Condrócitos/citologia , Condrócitos/efeitos dos fármacos , Condrogênese/genética , Condrogênese/fisiologia , Relação Dose-Resposta a Droga , Ativação Enzimática/efeitos dos fármacos , Glucuronidase/antagonistas & inibidores , Glucuronidase/metabolismo , Immunoblotting , Imuno-Histoquímica , Hibridização In Situ , Camundongos , Camundongos Endogâmicos C57BL , Oligossacarídeos/farmacologia , Técnicas de Cultura de Órgãos , Osteogênese/fisiologiaRESUMO
Objective: Reuse of clinical data has broad use in clinical, research, governmental, and business settings. This summary provides an update on the benefits, barriers to use with large clinical databases, policy frameworks that have been formulated, and challenges. Methods: This report highlights some recent publications on the diverse uses of clinical data and some policy initiatives to promote reuse. It also contains the opinions of the author. Results: Although many examples of the benefits of data reuse have been documented, this summary also reviews why the quality of clinical data needs to be the focus of future informatics work. Conclusion: The promise of reusing data outweighs potential risks, but concerns about privacy and the need to modernize our legal framework will be necessary to realize the full benefits of real-world evidence.
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Pesquisa Biomédica , Mineração de Dados , Disseminação de Informação , Confidencialidade , Registros Eletrônicos de Saúde , Genômica , HumanosRESUMO
As the Editors of leading international biomedical informatics journals, the authors report on a recent pattern of improper manuscript submissions to journals in our field. As a guide for future authors, we describe ethical and pragmatic issues related to submitting work for peer-reviewed journal publication. We propose a coordinated approach to the problem that our respective journals will follow. This Editorial is being jointly published in the following journals represented by the authors: Computer Methods and Programs in Biomedicine, International Journal of Medical Informatics, Journal of Biomedical Informatics, Journal of the American Medical Informatics Association, and Methods of Information in Medicine.
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Pesquisa Biomédica , Editoração , Retratação de Publicação como Assunto , Humanos , Jornalismo MédicoRESUMO
We studied the serum albumin level within 48 hours of hospitalization for acute illness to predict in-hospital death, length of stay, and readmission in 15,511 patients older than 40 years. Patients with low serum albumin levels (less than 34 g/L), who made up 21% of the population, were more likely to die, had longer hospital stays, and were readmitted sooner and more frequently than patients with normal albumin levels. The in-hospital mortality was 14% among patients with low albumin levels, as compared with 4% among patients with normal levels. Although the serum albumin level was a nonspecific marker, it was a stronger predictor of death, length of stay, and readmission than age. We conclude that the serum albumin level on admission is an important variable that should be incorporated in severity-of-illness measures based on physiologic indexes.
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Mortalidade Hospitalar , Tempo de Internação/estatística & dados numéricos , Readmissão do Paciente , Albumina Sérica/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/química , Boston/epidemiologia , Feminino , Hospitais com mais de 500 Leitos , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Valor Preditivo dos Testes , Análise de Regressão , Estudos Retrospectivos , Índice de Gravidade de DoençaRESUMO
BACKGROUND: Hospital computing systems play an important part in the communication of clinical information to physicians. We sought to determine whether computer-based alerts for hospitalized patients can affect physicians' behavior and improve patients' outcomes. METHODS: We performed a prospective time-series study to determine whether computerized alerts to physicians about rising creatinine levels in hospitalized patients receiving nephrotoxic or renally excreted medications led to more rapid adjustment or discontinuation of those medications, and to determine whether such alerts protected renal function. RESULTS: Laboratory data were observed for 20,228 hospitalizations, with documentation of 1573 events (instances of rising creatinine levels during treatment with a nephrotoxic or renally excreted drug). During the intervention period, doses were adjusted or medications discontinued an average of 21.6 hours sooner after such an event (P < .0001). For patients receiving nephrotoxic medications during the intervention period, the relative risk of serious renal impairment was 0.45 (95% confidence interval, 0.22 to 0.94) as compared with the control period, and the mean serum creatinine level was 14.1 mumol/L (0.16 mg/dL) lower on day 3 (P < .01) and 25.6 mumol/L (0.29 mg/dL) lower on day 7 (P < .05) after an event. Forty-four percent of physicians who responded to a questionnaire said that the alerts had been helpful in the care of their patients, whereas 28% found them annoying. Sixty-five percent wished to continue receiving alerts. CONCLUSIONS: Computer-based alerts regarding patients with rising creatinine levels affect physician behavior, prevent serious renal impairment, preserve renal function, and are accepted by clinicians.
Assuntos
Injúria Renal Aguda/prevenção & controle , Sistemas de Informação em Laboratório Clínico , Creatinina/sangue , Quimioterapia Assistida por Computador , Injúria Renal Aguda/sangue , Injúria Renal Aguda/induzido quimicamente , Adulto , Sistemas de Informação Hospitalar , Hospitalização , Humanos , Modelos Lineares , Automação de Escritório , Estudos Prospectivos , Inquéritos e Questionários , Resultado do TratamentoRESUMO
BACKGROUND: Excitement around the adoption of electronic communication between physicians and patients is tempered by the possibility of increased clinical and legal risk. If patients do not read messages in a timely fashion, duplicative communication efforts may be required and patient safety may be jeopardized. OBJECTIVE: We sought to assess the prevalence and risk profile of unread messages in a mature patient portal. METHODS: We analyzed six years of messages (2005-2010) from physicians to patients to determine the prevalence and associated characteristics of unread messages in a patient portal. We focused on clinical messages, and excluded announcements. Because some physicians sent clinical messages to groups of patients, we labeled messages sent to more than 5 patients as "outreach" messages and excluded them from general analyses. We performed a chart review of 75 clinical messages to assess for harm. RESULTS: We found that 3% of clinical messages were unread after 21 days. Messages arriving outside of business hours were slightly more likely to go unread (RR 1.15 95% CI 1.11-1.19). Patients who were male (OR 1.14 CI 1.04-1.26) African American (OR 1.69 CI 1.29-2.22) or Hispanic (OR 1.74 CI 1.17-2.59), or in the lowest income group (OR 1.72 CI 1.19-2.49) were more likely to have unread messages. Chart review showed no evidence of harm, but 13% of sampled unread messages were associated with potential delays in care. Incidentally, we found 50% of the physician-initiated outreach messages were unread. CONCLUSIONS: Overall, secure messaging appears a safe form of communication, but systems to notify senders when messages are unread may have value. While most clinical messages were read, many outreach messages were not, providing caution for relying on such systems for information dissemination. Similar to other studies, differences by race and income were observed and require further study.
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Correio Eletrônico/estatística & dados numéricos , Internet , Humanos , Masculino , Segurança do Paciente , Médicos , Prevalência , Risco , Fatores de TempoRESUMO
PURPOSE, PATIENTS, AND METHODS: We used decision analysis to calculate the economic implications of routine testing for Neisseria gonorrhoeae infection of the cervix. This study compared performing endocervical cultures in all women seeking routine gynecologic care to a no-test strategy. Estimates derived from the medical literature were varied in a sensitivity analysis, and a Monte Carlo technique was used to incorporate the estimates of experts into the analysis. RESULTS: We found that routinely testing for gonorrhea reduced overall medical costs when the prevalence of infection exceeded 1.5 percent. This result was most sensitive to variation in the cost of the culture and the assumption that treatment prevents adverse sequelae. Reducing the estimated cost of the culture from $9 to $5 decreased the threshold prevalence from 1.5 to 0.8 percent. When we considered the variation in estimates of experts, the threshold prevalence increased from 1.5 to 2.1 percent. CONCLUSION: We conclude that a strategy of testing and treating selected women with risk factors for gonorrhea will not only reduce the likelihood of the development of serious adverse sequelae but will also result in a reduction of medical costs.
Assuntos
Gonorreia/economia , Programas de Rastreamento/economia , Cervicite Uterina/economia , Adulto , Análise Custo-Benefício , Técnicas de Apoio para a Decisão , Árvores de Decisões , Feminino , Gonorreia/epidemiologia , Humanos , Fatores de Risco , Salpingite/economia , Salpingite/epidemiologia , Cervicite Uterina/epidemiologiaRESUMO
Using the technique of decision analysis to evaluate data on single-modality and combined-modality therapy in Hodgkin's disease, we have been able to determine which treatment gives the best chance for prolonged disease-free survival in given settings. Both the potential of combined-modality therapy for inducing secondary hematologic malignancies and the rate of salvage with MOPP following relapse after radiotherapy have been studied to observe the effect of different rates of these variables on the therapeutic decision. An analysis of patients with known pathologic stage endorsed the continued use of extended-mantle radiotherapy for Stages IA and IIA disease; under most of the conditions analyzed, combined-modality therapy appeared the best option for Stage IIIA disease. The results for Stages IB and IIB disease showed neither combined-modality therapy nor total nodal irradiation to have a conclusive advantage. We also analyzed management decisions for patients who had not had pathologic staging. For this, probabilities of each pathologic stage were derived from a large patient data base and were incorporated into the decision analysis. The results of this analysis indicated that, despite the mortality of laparotomy, treatment designated according to pathologic stage was more effective than immediate combined-modality therapy for most types of patients. For certain patients in whom the clinical features could be used to predict a high probability of advanced disease, the most effective management was immediate MOPP chemotherapy without staging laparotomy.
Assuntos
Doença de Hodgkin/terapia , Adulto , Fatores Etários , Antineoplásicos/uso terapêutico , Tomada de Decisões , Quimioterapia Combinada , Feminino , Doença de Hodgkin/tratamento farmacológico , Doença de Hodgkin/patologia , Doença de Hodgkin/radioterapia , Humanos , Laparotomia , Linfografia , Masculino , Estadiamento de Neoplasias , Fatores SexuaisRESUMO
Because the National Cholesterol Education Program guidelines suggest that levels of total serum cholesterol less than 5.17 mmol/liter (200 mg/dl) are "desirable," we performed a retrospective observational analysis to determine the prevalence of coronary artery disease (CAD) in patients with total cholesterol less than 5.17 mmol/liter (200 mg/dl) and the prevalence of total cholesterol less than 5.17 mmol/liter (200 mg/dl) in patients with CAD by angiography. Cholesterol levels less than 5.17 mmol/liter (200 mg/dl) were found in 1,084 of 2,535 patients (42%) having cholesterol measured on hospital admission; 690 of these 1,084 (64%) had CAD. These patients were mostly men, had a family history of premature CAD, and 60% (414 of 690) had high-density lipoprotein (HDL) cholesterol less than 0.90 mmol/liter (35 mg/dl). In a separate group of patients defined from the same admission population but having angiographically established CAD, 32% (424 of 1,197) had a total cholesterol less than 5.17 mmol/liter (200 mg/dl), 59% of whom (252 of 424) had HDL less than 0.90 mmol/liter (35 mg/dl). An analysis of persons admitted electively for angiography (to exclude any effects of hospitalization per se on serum lipids) revealed a similar proportion of persons with total cholesterol less than 5.17 mmol/liter (200 mg/dl) (35%), CAD (82%), and HDL less than 0.90 mmol/liter (35 mg/dl).(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
HDL-Colesterol/sangue , Colesterol/sangue , Doença das Coronárias/sangue , Hospitalização , Angiografia Coronária , Doença das Coronárias/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Triglicerídeos/sangueRESUMO
Clinical, demographic and administrative data, including length of stay and institutional charges, were examined for 219 patients hospitalized for acute myocardial infarction (AMI). Neither length of stay nor charges differed among AMI patients with or without cardiovascular complications as defined by Medicare's diagnosis-related group (DRG) categories (DRG 121 and 122, respectively) for patients who are discharged alive. Myocardial enzyme peak levels are the best predictors of hospital resource consumption for patients with AMI when considered alone or in combination with other factors. The "cardiovascular complications" designated by discharge diagnoses did not reflect resource consumption in our patient population. Sixteen percent of the patients studied underwent cardiac catheterization during hospitalization. These patients stayed in the hospital longer and incurred 70% higher charges; nevertheless, they were grouped with the remaining AMI patients in the current DRG formulation. Clinical evaluations such as cardiovascular complications are subject to interpretation, and are therefore less credible than enzyme measurements for recognizing the severity of a patient's AMI. Reimbursement based on objective measurements may avoid payment inequities.
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Grupos Diagnósticos Relacionados , Seguro de Hospitalização/economia , Tempo de Internação/economia , Infarto do Miocárdio/economia , Idoso , Cateterismo Cardíaco/economia , Feminino , Humanos , Masculino , Miocárdio/enzimologia , Estudos Retrospectivos , Índice de Gravidade de Doença , Estados UnidosRESUMO
Cefotaxime, a third generation cephalosporin, is used throughout the world over a wide range of doses. The purpose of this paper is to discuss the rationale for determination of the optimal dosage and of adequate modes of administration. Among the factors determining in vivo activity, the most important are: (1) the time dependence of the antibacterial effect of cephalosporins, (2) the limited effect of increasing the drug concentration in contact with the bacteria and (3) the absence of a significant post-antibiotic effect. Combined with the rather short elimination half-life of cefotaxime, these factors argue for the use of a unitary dose of 1g in adult patients and for a 6- or 8-hour interval between doses. Information obtained from various animal models of infection are discussed. Clinical and bacteriological studies published in the international literature report a high rate of cure (between 80 and 100%) according to the type of infection and to the criteria of efficacy, with daily doses ranging from 2 to 4g bid or qid. The results obtained with the lowest doses are detailed, particularly for infections permitting the use of a low dosage. The necessity for increasing the dose is discussed in the following situations: (1) in specific infections requiring high local drug concentrations such as meningitis and endocarditis, (2) against micro-organisms exhibiting moderate susceptibility to cefotaxime (MIC greater than or equal to 1 mg/L) and (3) in immunocompromised patients. It is now well established that third generation cephalosporins have to be combined with other antimicrobial agents (e.g. aminoglycosides) for the treatment of patients with infections caused by bacteria able to become resistant. For susceptible strains, it has not been established that a synergistic effect of cefotaxime with another agent allows a reduction of the dosage of each member of the combination.
Assuntos
Infecções Bacterianas/tratamento farmacológico , Cefotaxima/administração & dosagem , Adulto , Cefotaxima/efeitos adversos , Cefotaxima/farmacocinética , Relação Dose-Resposta a Droga , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , HumanosRESUMO
We analyzed factors associated with the discharge diagnosis of delirium among 1,285 patients admitted to a major teaching hospital during a 2-year period, developed a model to classify the risk of developing delirium on the basis of clinical and diagnostic data, and tested the model on 471 patients admitted during the subsequent year. Using the multivariate technique of recursive partitioning, we identified four factors that distinguished 80% of all cases of delirium: 1) a urinary tract infection at any time during the hospital stay (odds ratio = 3.1; 95% confidence interval = 2.02-4.58); 2) no urinary tract infection, but low serum albumin on admission (odds ratio = 2.4; 95% confidence interval = 1.43-3.99); 3) neither urinary tract infection nor low serum albumin, but elevated white blood cell count on admission (odds ratio = 1.99; 95% confidence interval = 1.18-3.37); 4) none of these risk factors, but proteinuria on admission (odds ratio = 1.82; 95% confidence interval = 1.25-2.66). Patients without any of these four risk factors had the lowest probability of developing delirium during their hospital stay. Among individuals with delirium, in-hospital mortality and hospital charges were higher. The model developed accurately characterized the risk of delirium when it was tested on patients admitted to the same hospital during the subsequent year.
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Delírio/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Delírio/economia , Delírio/etiologia , Delírio/mortalidade , Feminino , Humanos , Tempo de Internação , Contagem de Leucócitos , Masculino , Probabilidade , Proteinúria/complicações , Fatores de Risco , Albumina Sérica/deficiência , Infecções Urinárias/complicaçõesRESUMO
In March of 1997, the National Research Council (NRC) of the National Academy of Sciences issued the report, "For the Record: Protecting Electronic Health Information." Concluding that the current practices at the majority of health care facilities in the United States are insufficient, the Council delineated both technical and organizational approaches to protecting electronic health information. The Beth Israel Deaconess Medical Center recently implemented a proof-of-concept, Web-based, cross-institutional medical record, CareWeb, which incorporates the NRC security and confidentiality recommendations. We report on our WWW implementation of the NRC recommendations and an initial evaluation of the balance between ease of use and confidentiality.
Assuntos
Redes de Comunicação de Computadores , Segurança Computacional , Confidencialidade , Sistemas Computacionais , Guias como Assunto , Estados UnidosRESUMO
Analysis of restriction fragment-length polymorphism of ribosomal DNA regions (ribotypes) was used as an epidemiologic tool to compare 25 pre- and posttreatment strains obtained from 12 patients treated with either cefpodoxime proxetil or amoxicillin-clavulanic acid. Ribotyping is a promising method to differentiate relapse from reinfection in the treatment failures of Escherichia coli urinary tract infections.
Assuntos
DNA Ribossômico , Infecções por Escherichia coli/microbiologia , Escherichia coli/classificação , Infecções Urinárias/microbiologia , Amoxicilina/uso terapêutico , Ceftizoxima/análogos & derivados , Ceftizoxima/uso terapêutico , Criança , Pré-Escolar , Ácido Clavulânico , Ácidos Clavulânicos/uso terapêutico , Diagnóstico Diferencial , Quimioterapia Combinada/uso terapêutico , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/tratamento farmacológico , Humanos , Lactente , Recidiva , Falha de Tratamento , Infecções Urinárias/tratamento farmacológico , Cefpodoxima ProxetilRESUMO
The authors analyzed two invasive procedures used to visualize the biliary tree, endoscopic retrograde cholangiopancreatography (ERCP) and percutaneous transhepatic cholangiography (PTC), and also explored the utility of preinvasive workups for patients with suspected cholestasis. For this analysis they used published ranges for success, fatality, complications, diagnostic accuracies of the procedures, and prognostic information about the underlying diseases. The choice between ERCP and PTC was found to be a "close call," but ERCP was generally favored as the first-choice procedure. The results suggest that noninvasive imaging does not help decide between ERCP and PTC. Although noninvasive imaging may identify those patients with common duct dilation, the higher success rate with PTC in these patients is offset by a slightly higher mortality rate. Consequently, the choice between ERCP and PTC remains close even if ultrasound has shown that biliary ducts are dilated. Furthermore, it is shown that these noninvasive tests are most useful when they can conclusively determine the presence or absence of biliary obstruction. For many patients, noninvasive imaging will not obviate the need for invasive tests.
Assuntos
Colestase/diagnóstico por imagem , Técnicas de Apoio para a Decisão , Algoritmos , Colangiografia/métodos , Colangiopancreatografia Retrógrada Endoscópica , Colestase/terapia , Árvores de Decisões , Humanos , ProbabilidadeRESUMO
Perlecan (Pln) is a large proteoglycan that can bear HS (heparan sulfate) and chondroitin sulfate glycosaminoglycans. Previous studies have demonstrated that Pln can interact with growth factors and cell surfaces either via its constituent glycosaminoglycan chains or core protein. Herein, we summarize studies demonstrating spatially and temporally regulated expression of Pln mRNA and protein in developing and mature cartilage. Mutations either in the Pln gene or in genes involved in glycosaminoglycan assembly result in severe cartilage phenotypes seen in both human syndromes and mouse model systems. In vitro studies demonstrate that Pln can trigger chondrogenic differentiation of multipotential mouse CH310T1/2 stem cells as well as maintain the phenotype of adult human chondrocytes. Structural mapping indicates that these activities lie entirely within domain I, a region unique to Pln, and that they require glycosaminoglycans. We also discuss data indicating that Pln cooperates with the key chondrogenic growth factor, BMP-2, to promote expression of hypertrophic chondrocyte markers. Collectively, these studies indicate that Pln is an important component of human cartilage and may have useful applications in tissue engineering and cartilage-directed therapeutics.
RESUMO
Using cognitive evaluation techniques, this study examines the effects of an electronic patient record and electronic mail on the interactions of health care providers. We find that the least structured communication methods are also the most heavily used: face-to-face, telephone, and electronic mail. Positive benefits of electronically-mediated interactions include improving communication, collaboration, and access to information to support decision-making. Negative factors include the potential for overloading clinicians with unwanted or unnecessary communications.
Assuntos
Redes de Comunicação de Computadores , Comportamento Cooperativo , Pessoal de Saúde , Comunicação , Humanos , Sistemas Computadorizados de Registros Médicos , Relações Médico-PacienteRESUMO
We examined observational data on the use of a clinical computing system in an effort to develop an empirical model of clinicians' information needs. Clinicians turn to information systems most often to review the results of diagnostic studies. After that, clinicians turn to information systems most often for communication. Bibliographic retrieval is the third most frequent reason for use, but is an order of magnitude less frequent than either results inquiry or electronic mail. Secondary retrieval of aggregate data from a clinical database is two orders of magnitude less common than primary retrieval. In a study at our hospital, clinicians gained access to an information resource during 16% of all general medical visits of patients with human immunodeficiency virus (HIV) infection while the patient was present. Insofar as our narrow focus on the primary care of HIV infection models the larger context of clinical medicine, clinicians are most often looking at information relating to therapeutics. Whatever knowledge structures are adopted, they must accommodate this observed need for therapeutic information.