You can lead a horse to water--improving physicians' knowledge of probabilities may not affect their decisions

Using cancer risk algorithms to improve risk estimates and referral decisions

Background

Cancer risk algorithms were introduced to clinical practice in the last decade, but they remain underused. We investigated whether General Practitioners (GPs) change their referral decisions in response to an unnamed algorithm, if decisions improve, and if changing decisions depends on having information about the algorithm and on whether GPs overestimated or underestimated risk.

Methods

157 UK GPs were presented with 20 vignettes describing patients with possible colorectal cancer symptoms. GPs gave their risk estimates and inclination to refer. They then saw the risk score of an unnamed algorithm and could update their responses. Half of the sample was given information about the algorithm's derivation, validation, and accuracy. At the end, we measured their algorithm disposition. We analysed the data using multilevel regressions with random intercepts by GP and vignette.

Results

We find that, after receiving the algorithm's estimate, GPs' inclination to refer changes 26% of the time and their decisions switch entirely 3% of the time. Decisions become more consistent with the NICE 3% referral threshold (OR 1.45 [1.27, 1.65], p < .001). The algorithm's impact is greatest when GPs have underestimated risk. Information about the algorithm does not have a discernible effect on decisions but it results in a more positive GP disposition towards the algorithm. GPs' risk estimates become better calibrated over time, i.e., move closer to the algorithm.

Conclusions

Cancer risk algorithms have the potential to improve cancer referral decisions. Their use as learning tools to improve risk estimates is promising and should be further investigated.

Unnecessary antibiotic treatment of children hospitalised with respiratory syncytial virus (RSV) bronchiolitis: risk factors and prescription patterns

OBJECTIVES

Respiratory syncytial virus (RSV) is a leading cause of respiratory tract infections, especially in young children. Antibiotics are often unnecessarily prescribed for the treatment of RSV. Such treatments affect antibiotic resistance in future bacterial infections of treated patients and the general population. This study aimed to understand risk factors for and patterns of unnecessary antibiotic prescription in children with RSV.

METHODS

In a single-centre, retrospective study in Israel, we obtained data for children aged ≤2 years (n = 1016) hospitalised for RSV bronchiolitis during 2008-2018 and ascertained not to have bacterial co-infections. Antibiotic misuse was defined as prescription of antibiotics during hospitalisation of the study population. Demographic and clinical variables were assessed as predictors of unnecessary antibiotic treatment in a multivariable logistic regression model.

RESULTS

The unnecessary antibiotic treatment rate of children infected with RSV and ascertained not to have a bacterial co-infection was estimated at 33.4% (95% CI 30.5-36.4%). An increased likelihood of antibiotic misuse was associated with drawing bacterial cultures and with variables indicative of a severe patient status such as lower oxygen saturation, higher body temperature, tachypnoea and prior recent emergency room visit. Older age and female sex were also associated with an increased likelihood of unnecessary antibiotic treatment.

CONCLUSIONS

Unnecessary antibiotic treatment in RSV patients was very common and may be largely attributed to physicians' perception of patients' severity. Improving prescription guidelines, implementing antibiotic stewardship programmes and utilising decision support systems may help achieve a better balance between prescribing and withholding antibiotic treatment.

A game theoretic approach reveals that discretizing clinical information can reduce antibiotic misuse

The overuse of antibiotics is exacerbating the antibiotic resistance crisis. Since this problem is a classic common-goods dilemma, it naturally lends itself to a game-theoretic analysis. Hence, we designed a model wherein physicians weigh whether antibiotics should be prescribed, given that antibiotic usage depletes its future effectiveness. The physicians' decisions rely on the probability of a bacterial infection before definitive laboratory results are available. We show that the physicians' equilibrium decision rule of antibiotic prescription is not socially optimal. However, we prove that discretizing the information provided to physicians can mitigate the gap between their equilibrium decisions and the social optimum of antibiotic prescription. Despite this problem's complexity, the effectiveness of the discretization solely depends on the type of information available to the physician to determine the nature of infection. This is demonstrated on theoretic distributions and a clinical dataset. Our results provide a game-theory based guide for optimal output of current and future decision support systems of antibiotic prescription.

Risk assessment and antibiotic prescribing decisions in children presenting to UK primary care with cough: a vignette study

OBJECTIVES

The validated 'STARWAVe' (Short illness duration, Temperature, Age, Recession, Wheeze, Asthma, Vomiting) clinical prediction rule (CPR) uses seven variables to guide risk assessment and antimicrobial stewardship in children presenting with cough. We aimed to compare general practitioners' (GPs) risk assessments and prescribing decisions to those of STARWAVe and assess the influence of the CPR's clinical variables.

SETTING

Primary care.

PARTICIPANTS

252 GPs, currently practising in the UK.

DESIGN

GPs were randomly assigned to view four (of a possible eight) clinical vignettes online. Each vignette depicted a child presenting with cough, who was described in terms of the seven STARWAVe variables. Systematically, we manipulated patient age (20 months vs 5 years), illness duration (3 vs 6 days), vomiting (present vs absent) and wheeze (present vs absent), holding the remaining STARWAVe variables constant.

OUTCOME MEASURES

Per vignette, GPs assessed risk of hospitalisation and indicated whether they would prescribe antibiotics or not.

RESULTS

GPs overestimated risk of hospitalisation in 9% of vignette presentations (88/1008) and underestimated it in 46% (459/1008). Despite underestimating risk, they overprescribed: 78% of prescriptions were unnecessary relative to GPs' own risk assessments (121/156), while 83% were unnecessary relative to STARWAVe risk assessments (130/156). All four of the manipulated variables influenced risk assessments, but only three influenced prescribing decisions: a shorter illness duration reduced prescribing odds (OR 0.14, 95% CI 0.08 to 0.27, p<0.001), while vomiting and wheeze increased them (OR_vomit 2.17, 95% CI 1.32 to 3.57, p=0.002; OR_wheeze 8.98, 95% CI 4.99 to 16.15, p<0.001).

CONCLUSIONS

Relative to STARWAVe, GPs underestimated risk of hospitalisation, overprescribed and appeared to misinterpret illness duration (prescribing for longer rather than shorter illnesses). It is important to ascertain discrepancies between CPRs and current clinical practice. This has implications for the integration of CPRs into the electronic health record and the provision of intelligible explanations to decision-makers.

Developing a framework for evidence-based grading and assessment of predictive tools for clinical decision support

BACKGROUND

Clinical predictive tools quantify contributions of relevant patient characteristics to derive likelihood of diseases or predict clinical outcomes. When selecting predictive tools for implementation at clinical practice or for recommendation in clinical guidelines, clinicians are challenged with an overwhelming and ever-growing number of tools, most of which have never been implemented or assessed for comparative effectiveness. To overcome this challenge, we have developed a conceptual framework to Grade and Assess Predictive tools (GRASP) that can provide clinicians with a standardised, evidence-based system to support their search for and selection of efficient tools.

METHODS

A focused review of the literature was conducted to extract criteria along which tools should be evaluated. An initial framework was designed and applied to assess and grade five tools: LACE Index, Centor Score, Well's Criteria, Modified Early Warning Score, and Ottawa knee rule. After peer review, by six expert clinicians and healthcare researchers, the framework and the grading of the tools were updated.

RESULTS

GRASP framework grades predictive tools based on published evidence across three dimensions: 1) Phase of evaluation; 2) Level of evidence; and 3) Direction of evidence. The final grade of a tool is based on the highest phase of evaluation, supported by the highest level of positive evidence, or mixed evidence that supports a positive conclusion. Ottawa knee rule had the highest grade since it has demonstrated positive post-implementation impact on healthcare. LACE Index had the lowest grade, having demonstrated only pre-implementation positive predictive performance.

CONCLUSION

GRASP framework builds on widely accepted concepts to provide standardised assessment and evidence-based grading of predictive tools. Unlike other methods, GRASP is based on the critical appraisal of published evidence reporting the tools' predictive performance before implementation, potential effect and usability during implementation, and their post-implementation impact. Implementing the GRASP framework as an online platform can enable clinicians and guideline developers to access standardised and structured reported evidence of existing predictive tools. However, keeping GRASP reports up-to-date would require updating tools' assessments and grades when new evidence becomes available, which can only be done efficiently by employing semi-automated methods for searching and processing the incoming information.

Potential impact of the validated Predicting Abusive Head Trauma (PredAHT) clinical prediction tool: A clinical vignette study

BACKGROUND

The validated Predicting Abusive Head Trauma (PredAHT) tool estimates the probability of abusive head trauma (AHT) in children <3 years old with intracranial injury.

OBJECTIVE

To explore the impact of PredAHT on clinicians' AHT probability estimates and child protection (CP) actions, and assess inter-rater agreement between their estimates and between their CP actions, before and after PredAHT.

PARTICIPANTS AND SETTING

Twenty-nine clinicians from different specialties, at teaching and community hospitals.

METHODS

Clinicians estimated the probability of AHT and indicated their CP actions in six clinical vignettes. One vignette described a child with AHT, another described a child with non-AHT, and four represented "gray" cases, where the diagnosis was uncertain. Clinicians calculated the PredAHT score, and reported whether this altered their estimate/actions. The 'think-aloud' method was used to capture the reasoning behind their responses. Analysis included linear modelling, linear mixed-effects modelling, chi-square tests, Fisher's exact tests, intraclass correlation, Gwet's AC₁ coefficient and thematic analysis.

RESULTS

Overall, PredAHT significantly influenced clinicians' probability estimates in all vignettes (p < 0.001), although the impact on individual clinicians varied. However, the influence of PredAHT on clinicians' CP actions was limited; after using PredAHT, 9/29 clinicians changed their CP actions in only 11/174 instances. Clinicians' AHT probability estimates and CP actions varied somewhat both before and after PredAHT. Qualitative data suggested that PredAHT may increase clinicians' confidence in their decisions when considered alongside other associated clinical, historical and social factors.

CONCLUSIONS

PredAHT significantly influenced clinicians' AHT probability estimates, but had minimal impact on their CP actions.

Fostering clinical reasoning in physiotherapy: comparing the effects of concept map study and concept map completion after example study in novice and advanced learners

BACKGROUND

Health profession learners can foster clinical reasoning by studying worked examples presenting fully worked out solutions to a clinical problem. It is possible to improve the learning effect of these worked examples by combining them with other learning activities based on concept maps. This study investigated which combinaison of activities, worked examples study with concept map completion or worked examples study with concept map study, fosters more meaningful learning of intervention knowledge in physiotherapy students. Moreover, this study compared the learning effects of these learning activity combinations between novice and advanced learners.

METHODS

Sixty-one second-year physiotherapy students participated in the study which included a pre-test phase, a 130-min guided-learning phase and a four-week self-study phase. During the guided and self-study learning sessions, participants had to study three written worked examples presenting the clinical reasoning for selecting electrotherapeutic currents to treat patients with motor deficits. After each example, participants engaged in either concept map completion or concept map study depending on which learning condition they were randomly allocated to. Students participated in an immediate post-test at the end of the guided-learning phase and a delayed post-test at the end of the self-study phase. Post-tests assessed the understanding of principles governing the domain of knowledge to be learned (conceptual knowledge) and the ability to solve new problems that have similar (i.e., near transfer) or different (i.e., far transfer) solution rationales as problems previously studied in the examples.

RESULTS

Learners engaged in concept map completion outperformed those engaged in concept map study on near transfer (p = .010) and far transfer (p < .001) performance. There was a significant interaction effect of learners' prior ability and learning condition on conceptual knowledge but not on near and far transfer performance.

CONCLUSIONS

Worked examples study combined with concept map completion led to greater transfer performance than worked examples study combined with concept map study for both novice and advanced learners. Concept map completion might give learners better insight into what they have and have not yet learned, allowing them to focus on those aspects during subsequent example study.

Assessing the impact of colonoscopy complications on use of colonoscopy among primary care physicians and other connected physicians: an observational study of older Americans

OBJECTIVES

Psychological biases can distort treatment decision-making. The availability heuristic is one such bias, wherein events that are recent, vivid or easily imagined are readily 'available' to memory and are therefore judged more likely to occur than expected based on epidemiological data. We assessed if the occurrence of a serious colonoscopy complication for a primary care physician's patient influenced colonoscopy rates for the physician's other patients.

DESIGN

Longitudinal study with time-varying exposure variables.

SETTING/PARTICIPANTS

Individuals living in 51 hospital referral regions across the USA identified based on enrolment in fee-for-service Medicare during 2005-2010. We assigned patients to a primary care physician based on office visits during the prior 2 years.

EXPOSURES

For each physician in each month, we calculated the proportion of patients assigned to them who had a colonoscopy. We identified two serious complications of which the primary care provider would very likely be aware: gastrointestinal bleed or perforation leading to hospitalisation or death within 14 days of colonoscopy.

MAIN OUTCOME MEASURES

We employed Poisson regression models including physician fixed effects to assess the change in number of colonoscopies in the four quarters following an adverse colonoscopy event.

RESULTS

We identified 5 360 191 patients assigned to 30 704 physicians. 4864 physicians (16%) had at least one patient with an adverse event. The estimated change in the quarterly number of colonoscopies among physicians' patients was significantly lower in quarter 2 following an adverse colonoscopy event (change=-2.1% (95% CI -3.4 to -0.8%)), before returning to the rate expected in the absence of an adverse event.

CONCLUSIONS

Having a patient experience a serious adverse colonoscopy event was associated with a small and temporary decline in colonoscopy rates among a physician's other patients. This finding provides empirical evidence for the influence of notable adverse events on care, possibly due to the availability heuristic.

Morbidity and Mortality Conference: Its Purpose Reclaimed and Grounded in Theory

ISSUE

The morbidity and mortality conference (MMC) remains a central activity within the departments of our academic healthcare institutions. It is deeply rooted in the premise that we can learn from our mistakes, thereby improving the care we provide. Recent advances in our understanding of medical error and quality improvement have challenged the value of traditional models of MMC. As a result the purpose of MMC has become clouded and ill-defined: Is it an educational conference that promotes mastery of clinical acumen, or is it a venue to drive quality improvement by addressing systems-based issues in delivering care? Or can it serve both purposes?

EVIDENCE

Review of the history of MMC, the literature, and critical application of education theory demonstrates the source of the confusion and the challenges in viewing it through the exclusive lens of either education or quality improvement. Application of experiential learning theory helps resolve this discord showing how the conference facilitates the development of clinical mastery while informing quality improvement programs about important and relevant systems-based issues.

IMPLICATION

Building on this, we present a model for MMC involving five essential elements: case-based involving an adverse patient event, anonymity for participants, expert guided critical analysis, reframing understanding of the case presentation and related systems-based factors, and projection to practice change. This model builds on previously described models, is grounded in the literature, and helps clarify its role from both the educational and the quality improvement perspectives.

Theory about Heuristic Strategies Based on Verbal Protocol Analysis: The Emperor Needs a Shave

A research report in the present issue of Medical Decision Making raises questions about the definition of heuristic strategies, the validity of conclusions drawn from the analysis of verbal protocols, and the tradeoff between rigor and relevance in research on the psychology of patient decision making.

Naturalistic Decision Making and Organizations: Reviewing Pragmatic Science

This article examines the similarities and differences between the traditions of naturalistic decision making and organizational decision making. Illustrative examples of successful NDM inquiry in healthcare organizations are reviewed, highlighting an area where these two pragmatic research paradigms overlap. Not only do researchers in these areas aim to improve our understanding of decision making, they provide practical and realistic alternatives to laboratory-based research on decision making. The article presents a number of propositions for future research on NDM and organizations.

Educational effectiveness, target, and content for prudent antibiotic use

Widespread antimicrobial use and concomitant resistance have led to a significant threat to public health. Because inappropriate use and overuse of antibiotics based on insufficient knowledge are one of the major drivers of antibiotic resistance, education about prudent antibiotic use aimed at both the prescribers and the public is important. This review investigates recent studies on the effect of interventions for promoting prudent antibiotics prescribing. Up to now, most educational efforts have been targeted to medical professionals, and many studies showed that these educational efforts are significantly effective in reducing antibiotic prescribing. Recently, the development of educational programs to reduce antibiotic use is expanding into other groups, such as the adult public and children. The investigation of the contents of educational programs for prescribers and the public demonstrates that it is important to develop effective educational programs suitable for each group. In particular, it seems now to be crucial to develop appropriate curricula for teaching medical and nonmedical (pharmacy, dentistry, nursing, veterinary medicine, and midwifery) undergraduate students about general medicine, microbial virulence, mechanism of antibiotic resistance, and judicious antibiotic prescribing.

Example-based learning: comparing the effects of additionally providing three different integrative learning activities on physiotherapy intervention knowledge

BACKGROUND

Example-based learning using worked examples can foster clinical reasoning. Worked examples are instructional tools that learners can use to study the steps needed to solve a problem. Studying worked examples paired with completion examples promotes acquisition of problem-solving skills more than studying worked examples alone. Completion examples are worked examples in which some of the solution steps remain unsolved for learners to complete. Providing learners engaged in example-based learning with self-explanation prompts has been shown to foster increased meaningful learning compared to providing no self-explanation prompts. Concept mapping and concept map study are other instructional activities known to promote meaningful learning. This study compares the effects of self-explaining, completing a concept map and studying a concept map on conceptual knowledge and problem-solving skills among novice learners engaged in example-based learning.

METHODS

Ninety-one physiotherapy students were randomized into three conditions. They performed a pre-test and a post-test to evaluate their gains in conceptual knowledge and problem-solving skills (transfer performance) in intervention selection. They studied three pairs of worked/completion examples in a digital learning environment. Worked examples consisted of a written reasoning process for selecting an optimal physiotherapy intervention for a patient. The completion examples were partially worked out, with the last few problem-solving steps left blank for students to complete. The students then had to engage in additional self-explanation, concept map completion or model concept map study in order to synthesize and deepen their knowledge of the key concepts and problem-solving steps.

RESULTS

Pre-test performance did not differ among conditions. Post-test conceptual knowledge was higher (P < .001) in the concept map study condition (68.8 ± 21.8%) compared to the concept map completion (52.8 ± 17.0%) and self-explanation (52.2 ± 21.7%) conditions. Post-test problem-solving performance was higher (P < .05) in the self-explanation (63.2 ± 16.0%) condition compared to the concept map study (53.3 ± 16.4%) and concept map completion (51.0 ± 13.6%) conditions. Students in the self-explanation condition also invested less mental effort in the post-test.

CONCLUSIONS

Studying model concept maps led to greater conceptual knowledge, whereas self-explanation led to higher transfer performance. Self-explanation and concept map study can be combined with worked example and completion example strategies to foster intervention selection.

Management of patients with sore throats in relation to guidelines: an interview study in Sweden

OBJECTIVE

To explore how a group of Swedish general practitioners (GPs) manage patients with a sore throat in relation to current guidelines as expressed in interviews.

DESIGN

Qualitative content analysis was used to analyse semi-structured interviews.

SETTING

Swedish primary care.

SUBJECTS

A strategic sample of 25 GPs.

MAIN OUTCOME MEASURES

Perceived management of sore throat patients.

RESULTS

It was found that nine of the interviewed GPs were adherent to current guidelines for sore throat and 16 were non-adherent. The two groups differed in terms of guideline knowledge, which was shared within the team for adherent GPs while idiosyncratic knowledge dominated for the non-adherent GPs. Adherent GPs had no or low concerns for bacterial infections and differential diagnosis whilst non-adherent GPs believed that in patients with a sore throat any bacterial infection should be identified and treated with antibiotics. Patient history and examination was mainly targeted by adherent GPs whilst for non-adherent GPs it was often redundant. Non-adherent GPs reported problems getting patients to abstain from antibiotics, whilst no such problems were reported in adherent GPs.

CONCLUSION

This interview study of sore throat management in a strategically sampled group of Swedish GPs showed that while two-thirds were non-adherent and had a liberal attitude to antibiotics one-third were guideline adherent with a restricted view on antibiotics. Non-adherent GPs revealed significant knowledge gaps. Adherent GPs had discussed guidelines within the primary care team while non-adherent GPs had not. Guideline implementation thus seemed to be promoted by knowledge shared in team discussions.

Long-term effects of an educational seminar on antibiotic prescribing by GPs: a randomised controlled trial

BACKGROUND

High levels of outpatient antibiotic use remain observed in many European countries. Several studies have shown a strong relationship between antibiotic use and bacterial resistance.

AIM

To assess the long-term effect of a standardised educational seminar on antibiotic prescriptions by GPs.

DESIGN AND SETTING

Randomised controlled trial of 171 GPs (of 203 initially randomised) in France.

METHOD

GPs in the control group (n = 99) received no antibiotic prescription recommendation. Intervention group GPs (n = 72) attended an interactive seminar presenting evidence-based guidelines on antibiotic prescription for respiratory infections. The proportion of prescriptions containing an antibiotic in each group and related costs were compared to the baseline up to 30 months following the intervention. Data were obtained from the National Health Insurance System database.

RESULTS

In the intervention group, 4-6 months after the intervention, there was a significant decrease in the proportion of prescriptions containing an antibiotic from 15.2 ± 5.4% to 12.3 ± 5.8% (-2.8% [95% CI = -3.8 to -1.9], P<0.001). By contrast, an increase was observed in controls from 15.3 ± 6.0 to 16.4 ± 6.7% (+1.1% [95% CI = +0.4 to +1.8], P<0.01), resulting in a between-group difference of 3.93% ([95% CI = 2.75 to 5.11], P<0.001). The between-group difference was maintained 30 months after intervention (1.99% [95% CI = 0.56 to 3.42], P<0.01). Persistence of the intervention effect over the entire study period was confirmed in a hierarchical multivariate analysis.

CONCLUSION

This randomised trial shows that a standardised and interactive educational seminar results in a long-term reduction in antibiotic prescribing and could justify a large-scale implementation of this intervention.

Effectiveness of physician-targeted interventions to improve antibiotic use for respiratory tract infections

BACKGROUND

Antibiotic use and concomitant resistance are increasing. Literature reviews do not unambiguously indicate which interventions are most effective in improving antibiotic prescribing practice.

AIM

To assess the effectiveness of physician-targeted interventions aiming to improve antibiotic prescribing for respiratory tract infections (RTIs) in primary care, and to identify intervention features mostly contributing to intervention success.

DESIGN AND SETTING

Analysis of a set of physician-targeted interventions in primary care.

METHOD

A literature search (1990-2009) for studies describing the effectiveness of interventions aiming to optimise antibiotic prescription for RTIs by primary care physicians. Intervention features were extracted and effectiveness sizes were calculated. Association between intervention features and intervention success was analysed in multivariate regression analysis.

RESULTS

This study included 58 studies, describing 87 interventions of which 60% significantly improved antibiotic prescribing; interventions aiming to decrease overall antibiotic prescription were more frequently effective than interventions aiming to increase first choice prescription. On average, antibiotic prescription was reduced by 11.6%, and first choice prescription increased by 9.6%. Multiple interventions containing at least 'educational material for the physician' were most often effective. No significant added value was found for interventions containing patient-directed elements. Communication skills training and near-patient testing sorted the largest intervention effects.

CONCLUSION

This review emphasises the importance of physician education in optimising antibiotic use. Further research should focus on how to provide physicians with the relevant knowledge and tools, and when to supplement education with additional intervention elements. Feasibility should be included in this process.

Role of biomarkers in the management of antibiotic therapy: an expert panel review II: clinical use of biomarkers for initiation or discontinuation of antibiotic therapy

Biomarker-guided initiation of antibiotic therapy has been studied in four conditions: acute pancreatitis, lower respiratory tract infection (LRTI), meningitis, and sepsis in the ICU. In pancreatitis with suspected infected necrosis, initiating antibiotics best relies on fine-needle aspiration and demonstration of infected material. We suggest that PCT be measured to help predict infection; however, available data are insufficient to decide on initiating antibiotics based on PCT levels. In adult patients suspected of community-acquired LRTI, we suggest withholding antibiotic therapy when the serum PCT level is low (<0.25 ng/mL); in patients having nosocomial LRTI, data are insufficient to recommend initiating therapy based on a single PCT level or even repeated measurements. For children with suspected bacterial meningitis, we recommend using a decision rule as an aid to therapeutic decisions, such as the Bacterial Meningitis Score or the Meningitest®; a single PCT level ≥0.5 ng/mL also may be used, but false-negatives may occur. In adults with suspected bacterial meningitis, we suggest integrating serum PCT measurements in a clinical decision rule to help distinguish between viral and bacterial meningitis, using a 0.5 ng/mL threshold. For ICU patients suspected of community-acquired infection, we do not recommend using a threshold serum PCT value to help the decision to initiate antibiotic therapy; data are insufficient to recommend using PCT serum kinetics for the decision to initiate antibiotic therapy in patients suspected of ICU-acquired infection. In children, CRP can probably be used to help discontinue therapy, although the evidence is limited. In adults, antibiotic discontinuation can be based on an algorithm using repeated PCT measurements. In non-immunocompromised out- or in- patients treated for RTI, antibiotics can be discontinued if the PCT level at day 3 is < 0.25 ng/mL or has decreased by >80-90%, whether or not microbiological documentation has been obtained. For ICU patients who have nonbacteremic sepsis from a known site of infection, antibiotics can be stopped if the PCT level at day 3 is < 0.5 ng/mL or has decreased by >80% relative to the highest level recorded, irrespective of the severity of the infectious episode; in bacteremic patients, a minimal duration of therapy of 5 days is recommended.

A qualitative study into the difficulties experienced by healthcare decision makers when reading a Cochrane diagnostic test accuracy review

BACKGROUND

Cochrane reviews are one of the best known and most trusted sources of evidence-based information in health care. While steps have been taken to make Cochrane intervention reviews accessible to a diverse readership, little is known about the accessibility of the newcomer to the Cochrane library: diagnostic test accuracy reviews (DTARs). The current qualitative study explored how healthcare decision makers, who varied in their knowledge and experience with test accuracy research and systematic reviews, read and made sense of DTARs.

METHODS

A purposive sample of clinicians, researchers and policy makers (n = 21) took part in a series of think-aloud interviews, using as interview material the first three DTARs published in the Cochrane library. Thematic qualitative analysis of the transcripts was carried out to identify patterns in participants' 'reading' and interpretation of the reviews and the difficulties they encountered.

RESULTS

Participants unfamiliar with the design and methodology of DTARs found the reviews largely inaccessible and experienced a range of difficulties stemming mainly from the mismatch between background knowledge and level of explanation provided in the text. Experience with systematic reviews of interventions did not guarantee better understanding and, in some cases, led to confusion and misinterpretation. These difficulties were further exacerbated by poor layout and presentation, which affected even those with relatively good knowledge of DTARs and had a negative impact not only on their understanding of the reviews but also on their motivation to engage with the text. Comparison between the readings of the three reviews showed that more accessible presentation, such as presenting the results as natural frequencies, significantly increased participants' understanding.

CONCLUSIONS

The study demonstrates that authors and editors should pay more attention to the presentation as well as the content of Cochrane DTARs, especially if the reports are aimed at readers with various levels of background knowledge and experience. It also raises the question as to the anticipated target audience of the reports and suggests that different groups of healthcare decision-makers may require different modes of presentation.

Effectiveness of a decision-training aid on referral prioritization capacity: a randomized controlled trial

BACKGROUND

In the community mental health field, occupational therapy students lack the capacity to prioritize referrals effectively.

OBJECTIVE

The purpose of this study was to test the effectiveness of a clinical decision-training aid on referral prioritization capacity.

DESIGN

A double-blind, parallel-group, randomized controlled trial was conducted using a judgment analysis approach.

SETTING

Each participant used the World Wide Web to prioritize referral sets at baseline, immediate posttest, and 2-wk follow-up. The intervention group was provided with training after baseline testing; control group was purely given instructions to continue with the task.

PARTICIPANTS

One hundred sixty-five students were randomly allocated to intervention (n = 87) or control (n = 81). Intervention. Written and graphical descriptions were given of an expert consensus standard explaining how referral information should be used to prioritize referrals.

MEASUREMENTS

Participants' prioritization ratings were correlated with the experts' ratings of the same referrals at each stage of testing, as well as to examine the effect on mean group scores, regression weights, and the lens model indices.

RESULTS

At baseline, no differences were found between control and intervention on rating capacity or demographic characteristics. Comparison of the difference in mean correlation baseline scores of the control and intervention group compared with immediate posttest showed a statistically significant result that was maintained at 2-wk follow-up. The effect size was classified as large. At immediate posttest and follow-up, the intervention group improved rating capacity, whereas the control group's capacity remained poor. The results of this study indicate that the decision-training aid has a positive effect on referral prioritization capacity.

CONCLUSIONS

This freely available, Web-based decision-training aid will be a valuable adjunct to the education of these novice health professionals internationally.

The impact of physician subspecialty training, risk calculation, and patient age on treatment recommendations in ocular hypertension

PURPOSE

To determine whether glaucoma subspecialty training, formal risk estimation, or patient age has an impact on physician treatment recommendations in cases of ocular hypertension.

DESIGN

Experimental study.

METHODS

Members of the American Academy of Ophthalmology (118) and American Glaucoma Society (58) were recruited. Each physician was first asked how many young and old patients with ocular hypertension he or she would treat to prevent someone from progressing to glaucoma (number needed to treat). The physicians then reviewed 100 simulated cases of patients with ocular hypertension and reported their likelihood to treat each case. Half of these cases were presented with an estimated risk of conversion to glaucoma within 5 years and half were presented without an estimate. The treatment recommendations were analyzed to determine whether subspecialty status or the presence of a risk calculation had any impact on treatment recommendations.

RESULTS

Both glaucoma specialists and non-glaucoma specialists were more likely to recommend treatment in cases for which a risk calculation was provided (P = .001). Furthermore, non-glaucoma specialists were more likely to recommend treatment for ocular hypertensive patients than were glaucoma specialists (P < .001). Finally, both groups indicated they were more likely to treat young patients than old.

CONCLUSIONS

Both provision of a risk estimate and lack of glaucoma subspecialty training were associated with physicians being more likely to treat ocular hypertension. These findings have implications with regard to ways in which the treatment of ocular hypertensive patients could be modified and possibly made more consistent with available evidence.

Training Novices to Make Expert, Occupationally Focused, Community Mental Health Referral Decisions

Introduction:

Currently, British health policy requires services to be prioritised according to an individual's level of need. This is particularly necessary for community mental health services, where referral demand far exceeds service availability.

Purpose:

The purpose of this study was to use expert occupational therapists' referral prioritisation policies, derived from judgement analysis, to train novices in the skill of referral prioritisation.

Method:

The therapists' policies chosen were those that supported the occupationally focused practice advocated by the profession. Thirty-seven pre-registration students were asked to prioritise a set of referrals, before and after being trained with graphical and descriptive representations of these experts' policies.

Findings:

Pre-training, the students overvalued the client's history of violence and undervalued the reason for referral and the client's diagnosis, as compared with the experts. Post-training, the students' policies were better matched to those of the experts. The effect of training was demonstrated through several measures: more accurate prioritisation scores when matched with expert ratings on the same referrals, improved consistency on repeat referrals and higher group agreement.

Conclusion:

Decision training may be useful in promoting the type of service that aims to target clients' occupational needs in the field of community mental health.

Overestimation error and unnecessary antibiotic prescriptions for acute cystitis in adult women

BACKGROUND

Empiric antibiotic prescribing for suspected acute cystitis may lead to unnecessary prescriptions when urine cultures are negative. This study assessed whether physician overestimation of the likelihood of bacterial infection contributed to unnecessary antibiotic prescriptions.

METHODS

This was a cross-sectional study in Toronto, Canada, from 1998 to 2000 of 231 women 16 years and older who underwent standardized clinical assessments and urine culture testing. The main outcome was an unnecessary antibiotic prescription, defined as a prescription where the urine culture was negative. The difference between physician estimates of the likelihood of a positive urine culture and the measured culture rate for women with similar symptoms was used to measure overestimation error. Logistic regression was used to assess associations between unnecessary prescriptions and clinical factors or overestimation error. Multiple logistic regression was used to adjust for the effect of clinical factors.

RESULTS

Of 230 women assessed, 186 (80.9%) were prescribed antibiotics and 74 (32.2%) were prescribed an unnecessary antibiotic where the urine culture was negative. When an overestimation error above the median value (14.75%) was present, the odds of an unnecessary antibiotic prescription were increased (adjusted odds ratio = 3.72; 95% confidence interval = 1.75-7.89). A high overestimation error was associated with the symptoms of urinary frequency or suprapubic tenderness and costovertebral angle tenderness on examination.

CONCLUSIONS

Physician overestimation of the likelihood of a positive urine culture in women with symptoms of acute cystitis was associated with unnecessary antibiotic prescribing. Antibiotic overuse may be reduced by developing treatment strategies that deemphasize nonspecific clinical findings that contribute to physician overestimation error.

Procalcitonin for guidance of antibiotic therapy

Procalcitonin is a surrogate biomarker for estimating the likelihood of a bacterial infection. Procalcitonin-guided initiation and termination of antibiotic therapy is a novel approach utilized to reduce antibiotic overuse. This is essential to decrease the risk of side effects and emerging bacterial multiresistance. Interpretation of procalcitonin levels must always comprise the clinical setting and knowledge about assay characteristics. Only highly sensitive procalcitonin assays should be used in clinical practice and cut-off ranges must be adapted to the disease and setting. Highly sensitive procalcitonin measurements, embedded in diagnosis-specific clinical algorithms, have been shown to markedly reduce the overuse of antibiotic therapy without increasing risk to patients in 11 randomized controlled trials including over 3500 patients from different European countries. In primary care and emergency department patients with mild and mostly viral respiratory infections (acute bronchitis), the initial prescription of antibiotics was reduced by 30-80%. In hospitalized and more severely ill patients with community-acquired pneumonia and sepsis, the main effect was a reduction of the duration of antibiotic courses by 25-65%. This review aims to provide physicians with an overview of the strengths and limitations of procalcitonin guidance for antibiotic therapy when used in different clinical settings and in patients with different underlying infections.

A new method for determining physician decision thresholds using empiric, uncertain recommendations

Background

The concept of risk thresholds has been studied in medical decision making for over 30 years. During that time, physicians have been shown to be poor at estimating the probabilities required to use this method. To better assess physician risk thresholds and to more closely model medical decision making, we set out to design and test a method that derives thresholds from actual physician treatment recommendations. Such an approach would avoid the need to ask physicians for estimates of patient risk when trying to determine individual thresholds for treatment. Assessments of physician decision making are increasingly relevant as new data are generated from clinical research. For example, recommendations made in the setting of ocular hypertension are of interest as a large clinical trial has identified new risk factors that should be considered by physicians. Precisely how physicians use this new information when making treatment recommendations has not yet been determined.

Results

We derived a new method for estimating treatment thresholds using ordinal logistic regression and tested it by asking ophthalmologists to review cases of ocular hypertension before expressing how likely they would be to recommend treatment. Fifty-eight physicians were recruited from the American Glaucoma Society. Demographic information was collected from the participating physicians and the treatment threshold for each physician was estimated. The method was validated by showing that while treatment thresholds varied over a wide range, the most common values were consistent with the 10-15% 5-year risk of glaucoma suggested by expert opinion and decision analysis.

Conclusions

This method has advantages over prior means of assessing treatment thresholds. It does not require physicians to explicitly estimate patient risk and it allows for uncertainty in the recommendations. These advantages will make it possible to use this method when assessing interventions intended to alter clinical decision making.

Risk Judgment by General Dental Practitioners: Rational but Uninformed

Background

Decisions by dentists to administer antibiotic prophylaxis to prevent infectious complications in patients involves professional risk assessment. While recommendations for rational use have been published, several studies have shown that dentists have low adherence to these recommendations.

Objective

To examine general dental practitioners’ (GDPs’) assessments of the risk of complications if not administering antibiotic prophylaxis in connection with dental procedures in patients with specific medical conditions.

Methods

Postal questionnaires in combination with telephone interviews. Risk assessments were made using visual analogue scales (VAS), where zero represented “insignificant risk” and 100 represented a “very significant risk”.

Results

Response rate: 51%. The mean risk assessments were higher for GDPs who administered antibiotics (mean = 54, SD = 23, range 26–72 mm on the VAS) than those who did not (mean = 14, SD = 12, range 7–31 mm) (P < 0.05). Generally, GDPs made higher risk assessments for patients with medical conditions that are included in recommendations than those with conditions that are not included. Overall, risk assessments were higher for tooth removal than for scaling or root canal treatment, even though the risk assessments should be considered equal for these interventions.

Conclusions

GDPs’ risk assessments were rational but uninformed. They administered antibiotics in a manner that was consistent with their risk assessments. Their risk assessments, however, were overestimated. Inaccurate judgments of risk should not be expected to disappear in the presence of new information. To achieve change, clinicians must be motivated to improve behaviour and an evidence-based implementation strategy is required.

A universal model of diagnostic reasoning

Clinical judgment is a critical aspect of physician performance in medicine. It is essential in the formulation of a diagnosis and key to the effective and safe management of patients. Yet, the overall diagnostic error rate remains unacceptably high. In more than four decades of research, a variety of approaches have been taken, but a consensus approach toward diagnostic decision making has not emerged. In the last 20 years, important gains have been made in psychological research on human judgment. Dual-process theory has emerged as the predominant approach, positing two systems of decision making, System 1 (heuristic, intuitive) and System 2 (systematic, analytical). The author proposes a schematic model that uses the theory to develop a universal approach toward clinical decision making. Properties of the model explain many of the observed characteristics of physicians' performance. Yet the author cautions that not all medical reasoning and decision making falls neatly into one or the other of the model's systems, even though they provide a basic framework incorporating the recognized diverse approaches. He also emphasizes the complexity of decision making in actual clinical situations and the urgent need for more research to help clinicians gain additional insight and understanding regarding their decision making.

Vignette studies of medical choice and judgement to study caregivers' medical decision behaviour: systematic review

Background

Vignette studies of medical choice and judgement have gained popularity in the medical literature. Originally developed in mathematical psychology they can be used to evaluate physicians' behaviour in the setting of diagnostic testing or treatment decisions. We provide an overview of the use, objectives and methodology of these studies in the medical field.

Methods

Systematic review. We searched in electronic databases; reference lists of included studies. We included studies that examined medical decisions of physicians, nurses or medical students using cue weightings from answers to structured vignettes. Two reviewers scrutinized abstracts and examined full text copies of potentially eligible studies. The aim of the included studies, the type of clinical decision, the number of participants, some technical aspects, and the type of statistical analysis were extracted in duplicate and discrepancies were resolved by consensus.

Results

30 reports published between 1983 and 2005 fulfilled the inclusion criteria. 22 studies (73%) reported on treatment decisions and 27 (90%) explored the variation of decisions among experts. Nine studies (30%) described differences in decisions between groups of caregivers and ten studies (33%) described the decision behaviour of only one group. Only six studies (20%) compared decision behaviour against an empirical reference of a correct decision. The median number of considered attributes was 6.5 (IQR 4–9), the median number of vignettes was 27 (IQR 16–40). In 17 studies, decision makers had to rate the relative importance of a given vignette; in six studies they had to assign a probability to each vignette. Only ten studies (33%) applied a statistical procedure to account for correlated data.

Conclusion

Various studies of medical choice and judgement have been performed to depict weightings of the value of clinical information from answers to structured vignettes of care givers. We found that the design and analysis methods used in current applications vary considerably and could be improved in a large number of cases.

Do clinicians always maximize patient outcomes? A conjoint analysis of preferences for carotid artery testing

OBJECTIVES

The value clinicians place on diagnostic information is subject to psychological influences and systematic biases, but there is limited evidence of how these factors may affect patients' health outcomes. We assessed the relative value attached by experienced clinicians to different diagnostic test characteristics and how their preferences relate to patient outcomes, focusing on strategies for testing symptomatic patients for carotid artery stenosis.

METHODS

Using conjoint analysis, experienced neurologists and vascular surgeons ranked 10 diagnostic strategies defined in terms of four characteristics. Clinicians' preferences were analysed using an ordered probit model and compared with those obtained using a risk neutral expected value (EV) model developed to predict the consequences of each strategy as if the clinicians' sole goal were to optimize patient outcome. Results were tested for internal consistency and robustness to key model assumptions.

RESULTS

Preferences for positive predictive value (PPV), relative to negative predictive value (NPV), elicited from the clinicians diverged substantially from those estimated by the EV model based on 5-year stroke-free survival (ratios of -0.8 and -32.8, respectively). Conversely, preferences for NPV, relative to test morbidity, from the two models matched closely.

CONCLUSIONS

Clinicians attached substantially more importance to the PPV of carotid artery tests than would be justified by their impact on patient outcomes. Cognitive errors and attitudes to risk are likely to play an important role in explaining this finding. This study casts doubts on the validity of common assumptions made in the evaluation of health interventions, and in clinical and policy decisions.

Can antibiotic prescriptions in respiratory tract infections be improved? A cluster-randomized educational intervention in general practice--the Prescription Peer Academic Detailing (Rx-PAD) Study [NCT00272155]

Background

More than half of all antibiotic prescriptions in general practice are issued for respiratory tract infections (RTIs), despite convincing evidence that many of these infections are caused by viruses. Frequent misuse of antimicrobial agents is of great global health concern, as we face an emerging worldwide threat of bacterial antibiotic resistance. There is an increasing need to identify determinants and patterns of antibiotic prescribing, in order to identify where clinical practice can be improved.

Methods/Design

Approximately 80 peer continuing medical education (CME) groups in southern Norway will be recruited to a cluster randomized trial. Participating groups will be randomized either to an intervention- or a control group. A multifaceted intervention has been tailored, where key components are educational outreach visits to the CME-groups, work-shops, audit and feedback. Prescription Peer Academic Detailers (Rx-PADs), who are trained GPs, will conduct the educational outreach visits. During these visits, evidence-based recommendations of antibiotic prescriptions for RTIs will be presented and software will be handed out for installation in participants PCs, enabling collection of prescription data. These data will subsequently be linked to corresponding data from the Norwegian Prescription Database (NorPD). Individual feedback reports will be sent all participating GPs during and one year after the intervention. Main outcomes are baseline proportion of inappropriate antibiotic prescriptions for RTIs and change in prescription patterns compared to baseline one year after the initiation of the tailored pedagogic intervention.

Discussion

Improvement of prescription patterns in medical practice is a challenging task. A thorough evaluation of guidelines for antibiotic treatment in RTIs may impose important benefits, whereas inappropriate prescribing entails substantial costs, as well as undesirable consequences like development of antibiotic resistance. Our hypothesis is that an educational intervention program will be effective in improving prescription patterns by reducing the total number of antibiotic prescriptions, as well as reducing the amount of broad-spectrum antibiotics, with special emphasis on macrolides.

Interventions to improve antibiotic prescribing practices in ambulatory care

BACKGROUND

The development of resistance to antibiotics by many important human pathogens has been linked to exposure to antibiotics over time. The misuse of antibiotics for viral infections (for which they are of no value) and the excessive use of broad spectrum antibiotics in place of narrower spectrum antibiotics have been well-documented throughout the world. Many studies have helped to elucidate the reasons physicians use antibiotics inappropriately.

OBJECTIVES

To systematically review the literature to estimate the effectiveness of professional interventions, alone or in combination, in improving the selection, dose and treatment duration of antibiotics prescribed by healthcare providers in the outpatient setting; and to evaluate the impact of these interventions on reducing the incidence of antimicrobial resistant pathogens.

SEARCH STRATEGY

We searched the Cochrane Effective Practice and Organisation of Care Group (EPOC) specialized register for studies relating to antibiotic prescribing and ambulatory care. Additional studies were obtained from the bibliographies of retrieved articles, the Scientific Citation Index and personal files.

SELECTION CRITERIA

We included all randomised and quasi-randomised controlled trials (RCT and QRCT), controlled before and after studies (CBA) and interrupted time series (ITS) studies of healthcare consumers or healthcare professionals who provide primary care in the outpatient setting. Interventions included any professional intervention, as defined by EPOC, or a patient-based intervention.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed study quality.

MAIN RESULTS

Thirty-nine studies examined the effect of printed educational materials for physicians, audit and feedback, educational meetings, educational outreach visits, financial and healthcare system changes, physician reminders, patient-based interventions and multi-faceted interventions. These interventions addressed the overuse of antibiotics for viral infections, the choice of antibiotic for bacterial infections such as streptococcal pharyngitis and urinary tract infection, and the duration of use of antibiotics for conditions such as acute otitis media. Use of printed educational materials or audit and feedback alone resulted in no or only small changes in prescribing. The exception was a study documenting a sustained reduction in macrolide use in Finland following the publication of a warning against their use for group A streptococcal infections. Interactive educational meetings appeared to be more effective than didactic lectures. Educational outreach visits and physician reminders produced mixed results. Patient-based interventions, particularly the use of delayed prescriptions for infections for which antibiotics were not immediately indicated effectively reduced antibiotic use by patients and did not result in excess morbidity. Multi-faceted interventions combining physician, patient and public education in a variety of venues and formats were the most successful in reducing antibiotic prescribing for inappropriate indications. Only one of four studies demonstrated a sustained reduction in the incidence of antibiotic-resistant bacteria associated with the intervention.

AUTHORS' CONCLUSIONS

The effectiveness of an intervention on antibiotic prescribing depends to a large degree on the particular prescribing behaviour and the barriers to change in the particular community. No single intervention can be recommended for all behaviours in any setting. Multi-faceted interventions where educational interventions occur on many levels may be successfully applied to communities after addressing local barriers to change. These were the only interventions with effect sizes of sufficient magnitude to potentially reduce the incidence of antibiotic-resistant bacteria. Future research should focus on which elements of these interventions are the most effective. In addition, patient-based interventions and physician reminders show promise and innovative methods such as these deserve further study.

Procalcitonin-guided antibiotic use versus a standard approach for acute respiratory tract infections in primary care: study protocol for a randomised controlled trial and baseline characteristics of participating general practitioners [ISRCTN73182671]

BACKGROUND

Acute respiratory tract infections (ARTI) are among the most frequent reasons for consultations in primary care. Although predominantly viral in origin, ARTI often lead to the prescription of antibiotics for ambulatory patients, mainly because it is difficult to distinguish between viral and bacterial infections. Unnecessary antibiotic use, however, is associated with increased drug expenditure, side effects and antibiotic resistance. A novel approach is to guide antibiotic therapy by procalcitonin (ProCT), since serum levels of ProCT are elevated in bacterial infections but remain lower in viral infections and inflammatory diseases. The aim of this trial is to compare a ProCT-guided antibiotic therapy with a standard approach based on evidence-based guidelines for patients with ARTI in primary care.

METHODS/DESIGN

This is a randomised controlled trial in primary care with an open intervention. Adult patients judged by their general practitioner (GP) to need antibiotics for ARTI are randomised in equal numbers either to standard antibiotic therapy or to ProCT-guided antibiotic therapy. Patients are followed-up after 1 week by their GP and after 2 and 4 weeks by phone interviews carried out by medical students blinded to the goal of the trial. Exclusion criteria for patients are antibiotic use in the previous 28 days, psychiatric disorders or inability to give written informed consent, not being fluent in German, severe immunosuppression, intravenous drug use, cystic fibrosis, active tuberculosis, or need for immediate hospitalisation. The primary endpoint is days with restrictions from ARTI within 14 days after randomisation. Secondary outcomes are antibiotic use in terms of antibiotic prescription rate and duration of antibiotic treatment in days, days off work and days with side-effects from medication within 14 days, and relapse rate from the infection within 28 days after randomisation.

DISCUSSION

We aim to include 600 patients from 50 general practices in the Northwest of Switzerland. Data from the registry of the Swiss Medical Association suggests that our recruited GPs are representative of all eligible GPs with respect to age, proportion of female physicians, specialisation, years of postgraduate training and years in private practice.

Are we too fixated on clinical trial data? The case for using embedded case histories to influence prescribing

This article examines the assumptions used to support the strategic and tactical use of clinical trial data as the main type of information provided by pharmaceutical marketers. Evidence is presented which suggests that doctors use clinical trial data to construct general beliefs about a disease or product and that it is often used incorrectly when assessing the probability that a patient has a specific disease. Further evidence is examined which suggests that clinical experience is the most important type of information used when doctors make specific prescription decisions. A call is made for the pharmaceutical industry to address the need for experiential information by examining ways to provide doctors with detailed patient case histories.

Optimizing antibiotic prescribing for acute cough in general practice: a cluster-randomized controlled trial

OBJECTIVES

To assess the effect of a tailored professional intervention, including academic detailing, on antibiotic prescribing for acute cough.

METHODS

In a cluster-randomized controlled before and after study 85 Flemish GPs included adult patients with acute cough consulting in the periods February-April 2000 and 2001. The intervention consisted of a clinical practice guideline for acute cough, an educational outreach visit and a postal reminder to support its implementation in January 2001. Antibiotic prescribing rates and patients' symptom resolution were the main outcome measures.

RESULTS

Thirty-six of 42 GPs received the intervention and 35 of 43 GPs served as controls; 1503 patients were eligible for analysis. Only in the intervention group were patients less likely to receive antibiotics after the intervention [OR(adj) (95% CI)=0.56 (0.36-0.87)]. Prescribed antibiotics were also more in line with the guideline in the intervention group [1.90 (0.96-3.75)] and less expensive from the perspective of the National Sickness and Invalidity Insurance Institute [MD(adj) (95% CI)= Euro -6.89 [-11.77-(-2.02)]]. No significant differences were found between the groups for the time to symptom resolution.

CONCLUSIONS

An (inter)actively delivered tailored intervention implementing a guideline for acute cough is successful in optimizing antibiotic prescribing without affecting patients' symptom resolution. Further research efforts should be devoted to cost-effectiveness studies of such interventions.

Comparative impact of guidelines, clinical data, and decision support on prescribing decisions: an interactive web experiment with simulated cases

OBJECTIVE

The aim of this study was to compare the clinical impact of computerized decision support with and without electronic access to clinical guidelines and laboratory data on antibiotic prescribing decisions.

DESIGN

A crossover trial was conducted of four levels of computerized decision support-no support, antibiotic guidelines, laboratory reports, and laboratory reports plus a decision support system (DSS), randomly allocated to eight simulated clinical cases accessed by the Web.

MEASUREMENTS

Rate of intervention adoption was measured by frequency of accessing information support, cost of use was measured by time taken to complete each case, and effectiveness of decision was measured by correctness of and self-reported confidence in individual prescribing decisions. Clinical impact score was measured by adoption rate and decision effectiveness.

RESULTS

Thirty-one intensive care and infectious disease specialist physicians (ICPs and IDPs) participated in the study. Ventilator-associated pneumonia treatment guidelines were used in 24 (39%) of the 62 case scenarios for which they were available, microbiology reports in 36 (58%), and the DSS in 37 (60%). The use of all forms of information support did not affect clinicians' confidence in their decisions. Their use of the DSS plus microbiology report improved the agreement of decisions with those of an expert panel from 65% to 97% (p=0.0002), or to 67% (p=0.002) when antibiotic guidelines only were accessed. Significantly fewer IDPs than ICPs accessed information support in making treatment decisions. On average, it took 245 seconds to make a decision using the DSS compared with 113 seconds for unaided prescribing (p<0.001). The DSS plus microbiology reports had the highest clinical impact score (0.58), greater than that of electronic guidelines (0.26) and electronic laboratory reports (0.45).

CONCLUSION

When used, computer-based decision support significantly improved decision quality. In measuring the impact of decision support systems, both their effectiveness in improving decisions and their likely rate of adoption in the clinical environment need to be considered. Clinicians chose to use antibiotic guidelines for one third and microbiology reports or the DSS for about two thirds of cases when they were available to assist their prescribing decisions.

Which clinical decisions benefit from automation? A task complexity approach

OBJECTIVE

To describe a model for analysing complex medical decision making tasks and for evaluating their suitability for automation.

METHOD

Assessment of a decision task's complexity in terms of the number of elementary information processes (EIPs) and the potential for cognitive effort reduction through EIP minimisation using an automated decision aid.

RESULTS

The model consists of five steps: (1) selection of the domain and relevant tasks; (2) evaluation of the knowledge complexity for tasks selected; (3) identification of cognitively demanding tasks; (4) assessment of unaided and aided effort requirements for this task accomplishment; and (5) selection of computational tools to achieve this complexity reduction. The model is applied to the task of antibiotic prescribing in critical care and the most complex components of the task identified. Decision aids to support these components can provide a significant reduction of cognitive effort suggesting this is a decision task worth automating.

CONCLUSION

We view the role of decision support for complex decision to be one of task complexity reduction, and the model described allows for task automation without lowering decision quality and can assist decision support systems developers.

About time: diagnostic guidelines that help clinicians

Clinical guidelines often make recommendations on the use of diagnostic tests. Compared with sensitivity and specificity, the use of pre- and post-test probabilities allows a more explicit and rational selection and interpretation of diagnostic tests. Ideally, clinical guidelines relating to diagnosis should routinely incorporate this information to enhance individualised decision making. We report our experience of incorporating pre- and post-test probabilities into a guideline on the investigation of women with postmenopausal bleeding developed by the Scottish Intercollegiate Guidelines Network. Issues relating to their application are highlighted, including the limitations of available evidence on diagnostic tests and prevalence of disease, acceptability to guideline users, and the uncertain impact on actual clinical decision making. Despite these potential difficulties, the incorporation of data on pre- and post-test probabilities into the development and presentation of guideline recommendations may offer an important opportunity to make clinical decision making more transparent for both clinicians and patients.

Factors influencing physicians' reported use of anticoagulation therapy in nonvalvular atrial fibrillation: a cross-sectional survey

BACKGROUND

Some elderly patients with nonvalvular atrial fibrillation (NVAF) who might benefit from warfarin therapy do not receive it.

OBJECTIVE

The goal of this cross-sectional study was to identify physicians' attitudes and beliefs that are associated with their reported use of warfarin in case scenarios.

METHODS

A self-administered survey was mailed to a cross-section of general internists randomly selected from a national pool of physicians in the American Medical Association Masterfile. Fourteen clinical vignettes were used, incorporating various comorbid conditions and risk factors for either major bleeding episode or embolic cerebrovascular accident (CVA). The outcome measure was the number of case vignettes for which warfarin was recommended.

RESULTS

A total of 142 completed surveys (33% of 426 eligible respondents; 109 men, and 32 women [1 respondent did not provide gender]; mean [SD] age, 45 [10] years) were received. The median number of case vignettes for which warfarin was recommended was 10 (interquartile range, 8-12). We found no relationship between the perceived benefits of warfarin and its use in the case vignettes. However, the perceived risk for warfarin associated hemorrhage was strongly associated with reported warfarin use (P < 0.001). The physicians in our sample provided estimates of the annual rate of warfarin-associated intracerebral hemorrhage that were >10-fold higher than literature-based estimates, and physicians providing higher risk estimates tended to use warfarin less often. On multivariate logistic regression, physicians who recommended warfarin use in more vignettes were less likely to report anticipated regret of committing an error of omission (ischemic CVA in an untreated NVAF patient) (P < 0.001) or a loss-aversive risk preference (P = 0.027), and had a lower perceived annual risk for hemorrhage with warfarin (P < 0.001). Physician age, sex, primary mechanism of reimbursement, academic appointment, and the NVAF patient volume all were unrelated to warfarin use.

CONCLUSIONS

Although the decision to use warfarin in NVAF was not driven by the perceived benefit, the perceived risks strongly affected warfarin use. Response bias is a potential limitation, but our data strongly suggest that physicians' attitudes toward anticipated regret and risk aversion can impact on their treatment recommendations.

Optimizing antibiotic prescribing for acute respiratory tract infections in an urban urgent care clinic

OBJECTIVE

To decrease unnecessary antibiotic use for acute respiratory tract infections in adults in a point-of-service health care setting.

DESIGN

Prospective, nonrandomized controlled trial.

SETTING

An urban urgent care clinic associated with the major indigent care hospital in Denver, Colorado between October 2000 and April 2001.

PATIENTS/PARTICIPANTS

Adults diagnosed with acute respiratory tract infections (bronchitis, sinusitis, pharyngitis, and nonspecific upper respiratory infection). A total of 554 adults were included in the baseline period (October to December 2000) and 964 adults were included in the study period (January to April 2001).

INTERVENTIONS

A provider educational session on recommendations for appropriate antibiotic use recently published by the Centers for Disease Control and Prevention, and placement of examination room posters were performed during the last week of December 2000. Study period patients who completed a brief, interactive computerized education (ICE) module were classified as being exposed to the full intervention, whereas study period patients who did not complete the ICE module were classified as being exposed to the limited intervention.

MEASUREMENTS AND MAIN RESULTS

The proportion of patients diagnosed with acute bronchitis who received antibiotics decreased from 58% during the baseline period to 30% and 24% among patients exposed to the limited and full intervention, respectively (P <.001 for intervention groups vs baseline). Antibiotic prescriptions for nonspecific upper respiratory tract infections decreased from 14% to 3% and 1% in the limited- and full-intervention groups, respectively (P <.001 for intervention groups vs baseline).

CONCLUSION

Antibiotic use for adults diagnosed with acute respiratory tract infections can be reduced in a point-of-service health care setting using a combination of patient and provider educational interventions.