Association of Pharmacist Interventions With Adverse Drug Events and Potential Adverse Drug Events.

BACKGROUND: Adverse drug events (ADEs) are a frequent cause of injury in patients. Our aim was to assess whether pharmacist interventions compared with no pharmacist intervention results in reduced ADEs and potential adverse drug events (PADEs). METHODS: We searched MEDLINE, Embase, and two other databases through September 19, 2022 for any RCT assessing the effect of a pharmacist intervention compared with no pharmacist intervention and reporting on ADEs or PADEs. The risk of bias was assessed using the Cochrane tool for RCTs. A random-effects model was used to pool summary results from individual RCTs. RESULTS: Fifteen RCTs met the inclusion criteria. The pooled results showed a statistically significant reduction in ADE associated with pharmacist intervention compared with no pharmacist intervention (RR = 0.86; [95% CI 0.80-0.94]; p = 0.0005) but not for PADEs (RR = 0.79; [95% CI 0.47-1.32]; p = 0.37). The heterogeneity was insignificant (I2 = 0%) for ADEs and substantial (I2 = 77%) for PADEs. Patients receiving a pharmacist intervention were 14% less likely for ADE than those who did not receive a pharmacist intervention. The estimated number of patients needed to prevent one ADE across all patient locations was 33. CONCLUSIONS: To our knowledge, this is the first systematic review and meta-analysis of RCTs seeking to understand the association of pharmacist interventions with ADEs and PADEs. The risk of having an ADE is reduced by a seventh for patients receiving a pharmacist care intervention versus no such intervention. The estimated number of patients needed to be followed across all patient locations to prevent one preventable ADE across all patient locations is 33.

Drug allergies documented in electronic health records of a large healthcare system.

BACKGROUND: The prevalence of drug allergies documented in electronic health records (EHRs) of large patient populations is understudied. OBJECTIVE: We aimed to describe the prevalence of common drug allergies and patient characteristics documented in EHRs of a large healthcare network over the last two decades. METHODS: Drug allergy data were obtained from EHRs of patients who visited two large tertiary care hospitals in Boston from 1990 to 2013. The prevalence of each drug and drug class was calculated and compared by sex and race/ethnicity. The number of allergies per patient was calculated and the frequency of patients having 1, 2, 3…, or 10+ drug allergies was reported. We also conducted a trend analysis by comparing the proportion of each allergy to the total number of drug allergies over time. RESULTS: Among 1 766 328 patients, 35.5% of patients had at least one reported drug allergy with an average of 1.95 drug allergies per patient. The most commonly reported drug allergies in this population were to penicillins (12.8%), sulfonamide antibiotics (7.4%), opiates (6.8%), and nonsteroidal anti-inflammatory drugs (NSAIDs) (3.5%). The relative proportion of allergies to angiotensin-converting enzyme (ACE) inhibitors and HMG CoA reductase inhibitors (statins) have more than doubled since early 2000s. Drug allergies were most prevalent among females and white patients except for NSAIDs, ACE inhibitors, and thiazide diuretics, which were more prevalent in black patients. CONCLUSION: Females and white patients may be more likely to experience a reaction from common medications. An increase in reported allergies to ACE inhibitors and statins is noteworthy.

Physician Perceptions and Beliefs about Generating and Providing a Clinical Summary of the Office Visit.

BACKGROUND: A core measure of the meaningful use of EHR incentive program is the generation and provision of the clinical summary of the office visit, or the after visit summary (AVS), to patients. However, little research has been conducted on physician perceptions and beliefs about the AVS. OBJECTIVES: Evaluate physician perceptions and beliefs about the AVS and the effect of the AVS on workload, patient outcomes, and the care the physician delivers. METHODS: A cross-sectional online survey of physicians at two academic medical centers (AMCs) in the northeast who are participating in the meaningful use EHR incentive program. RESULTS: Of the 1 795 physicians at both AMCs participating in the incentive program, 853 completed the survey for a response rate of 47.5%. Eighty percent of the respondents reported that the AVS was easy (very easy or quite easy or somewhat easy) to generate and provide to patients. Nonetheless, more than three-fourths of the respondents reported a negative effect of generating and providing the AVS on workload of office staff (78%) and workload of physicians (76%). Primary care physicians had more positive beliefs about the effect of the AVS on patient outcomes than specialists (p<0.001) and also had more positive beliefs about the effect of the AVS on the care they delivered than specialists (p<0.001). CONCLUSIONS: Achieving the core meaningful use measure of generating and providing the AVS was easy for physicians but it did not necessarily translate into positive beliefs about the effect of the AVS on patient outcomes or the care the physician delivered. Physicians also had negative beliefs about the effect of the AVS on workload. To promote positive beliefs among physicians around the AVS, organizations should obtain physician input into the design and implementation of the AVS and develop strategies to mitigate its negative impacts on workload.

Health Information Technology and Care Coordination: The Next Big Opportunity for Informatics?

The costs of care in the U.S. are very high, in part because canre is relatively uncoordinated. To begin to address this and other issues, health care reform was passed, including the notion of accountable care. Under acountable care arrangements, providers are at risk for the costs of the care they provide to groups of patients. Evaluation of costs has made it clear that a large proportion of these costs are in the post-acute setting, and also that many specific problems such as adverse events and unnecessary readmissions occur following transitions. However, the electronic health records of today do not provide a great deal of assistance with the coordination of care, and even the best organizations have relatively primitive systems with respect to care coordination, even though communication is absolutely central to better coordination of care and health information technology (HIT) is a powerful lever for improving communication. This paper identifies specific gaps in care coordination today, presents a framework for better coordinating care using HIT, then describes how specific technologies can be leveraged. Also discussed are the need to build and test specific interventions to improve HIT-related care coordination tools, and the key policy steps needed to accomplish this.

Task analysis of information technology-mediated medication management in outpatient care.

AIMS: Educating physicians in the procedural as well as cognitive skills of information technology (IT)-mediated medication management could be one of the missing links for the improvement of patient safety. We aimed to compose a framework of tasks that need to be addressed to optimize medication management in outpatient care. METHODS: Formal task analysis: decomposition of a complex task into a set of subtasks. First, we obtained a general description of the medication management process from exploratory interviews. Secondly, we interviewed experts in-depth to further define tasks and subtasks. SETTING: Outpatient care in different fields of medicine in six teaching and academic medical centres in the Netherlands and the United States. PARTICIPANTS: 20 experts. Tasks were divided up into procedural, cognitive and macrocognitive tasks and categorized into the three components of dynamic decision making. RESULTS: The medication management process consists of three components: (i) reviewing the medication situation; (ii) composing a treatment plan; and (iii) accomplishing and communicating a treatment and surveillance plan. Subtasks include multiple cognitive tasks such as composing a list of current medications and evaluating the reliability of sources, and procedural tasks such as documenting current medication. The identified macrocognitive tasks were: planning, integration of IT in workflow, managing uncertainties and responsibilities, and problem detection. CONCLUSIONS: All identified procedural, cognitive and macrocognitive skills should be included when designing education for IT-mediated medication management. The resulting framework supports the design of educational interventions to improve IT-mediated medication management in outpatient care.

Predicting bacteraemia in validated models--a systematic review.

Bacteraemia is associated with high mortality. Although many models for predicting bacteraemia have been developed, not all have been validated, and even when they were, the validation processes varied. We identified validated models that have been developed; asked whether they were successful in defining groups with a very low or high prevalence of bacteraemia; and whether they were used in clinical practice. Electronic databases were searched to identify studies that underwent validation on prediction of bacteraemia in adults. We included only studies that were able to define groups with low or high probabilities for bacteraemia (arbitrarily defined as below 3% or above 30%). Fifteen publications fulfilled inclusion criteria, including 59 276 patients. Eleven were prospective and four retrospective. Study populations and the parameters included in the different models were heterogeneous. Ten studies underwent internal validation; the model performed well in all of them. Twelve performed external validation. Of the latter, seven models were validated in a different hospital, using a new independent database. In five of these, the model performed well. After contacting authors, we found that none of the models was implemented in clinical practice. We conclude that heterogeneous studies have been conducted in different defined groups of patients with limited external validation. Significant savings to the system and the individual patient can be gained by refraining from performing blood cultures in groups of patients in which the probability of true bacteraemia is very low, while the probability of contamination is constant. Clinical trials of existing or new models should be done to examine whether models are helpful and safe in clinical use, preferably multicentre in order to secure utility and safety in diverse clinical settings.

Computerised physician order entry-related medication errors: analysis of reported errors and vulnerability testing of current systems.

IMPORTANCE: Medication computerised provider order entry (CPOE) has been shown to decrease errors and is being widely adopted. However, CPOE also has potential for introducing or contributing to errors. OBJECTIVES: The objectives of this study are to (a) analyse medication error reports where CPOE was reported as a 'contributing cause' and (b) develop 'use cases' based on these reports to test vulnerability of current CPOE systems to these errors. METHODS: A review of medication errors reported to United States Pharmacopeia MEDMARX reporting system was made, and a taxonomy was developed for CPOE-related errors. For each error we evaluated what went wrong and why and identified potential prevention strategies and recurring error scenarios. These scenarios were then used to test vulnerability of leading CPOE systems, asking typical users to enter these erroneous orders to assess the degree to which these problematic orders could be entered. RESULTS: Between 2003 and 2010, 1.04 million medication errors were reported to MEDMARX, of which 63 040 were reported as CPOE related. A review of 10 060 CPOE-related cases was used to derive 101 codes describing what went wrong, 67 codes describing reasons why errors occurred, 73 codes describing potential prevention strategies and 21 codes describing recurring error scenarios. Ability to enter these erroneous order scenarios was tested on 13 CPOE systems at 16 sites. Overall, 298 (79.5%) of the erroneous orders were able to be entered including 100 (28.0%) being 'easily' placed, another 101 (28.3%) with only minor workarounds and no warnings. CONCLUSIONS AND RELEVANCE: Medication error reports provide valuable information for understanding CPOE-related errors. Reports were useful for developing taxonomy and identifying recurring errors to which current CPOE systems are vulnerable. Enhanced monitoring, reporting and testing of CPOE systems are important to improve CPOE safety.

Physician beliefs about the impact of meaningful use of the EHR: a cross-sectional study.

BACKGROUND: As adoption and use of electronic health records (EHRs) grows in the United States, there is a growing need in the field of applied clinical informatics to evaluate physician perceptions and beliefs about the impact of EHRs. The meaningful use of EHR incentive program provides a suitable context to examine physician beliefs about the impact of EHRs. OBJECTIVE: Contribute to the sparse literature on physician beliefs about the impact of EHRs in areas such as quality of care, effectiveness of care, and delivery of care. METHODS: A cross-sectional online survey of physicians at two academic medical centers (AMCs) in the northeast who were preparing to qualify for the meaningful use of EHR incentive program. RESULTS: Of the 1,797 physicians at both AMCs who were preparing to qualify for the incentive program, 967 completed the survey for an overall response rate of 54%. Only 23% and 27% of physicians agreed or strongly agreed that meaningful use of the EHR will help them improve the care they personally deliver and improve quality of care respectively. Physician specialty was significantly associated with beliefs; e.g., 35% of primary care physicians agreed or strongly agreed that meaningful use will improve quality of care compared to 26% of medical specialists and 21% of surgical specialists (p=0.009). Satisfaction with outpatient EHR was also significantly related to all belief items. CONCLUSIONS: Only about a quarter of physicians in our study responded positively that meaningful use of the EHR will improve quality of care and the care they personally provide. These findings are similar to and extend findings from qualitative studies about negative perceptions that physicians hold about the impact of EHRs. Factors outside of the regulatory context, such as physician beliefs, need to be considered in the implementation of the meaningful use of the EHR incentive program.

Personal health records for patients with chronic disease: a major opportunity.

BACKGROUND: Personal health records (PHRs) connected to a physician's electronic health record system hold substantial promise for supporting and engaging patients with chronic disease. OBJECTIVES: To explore how U.S. health care organizations are currently utilizing PHRs for chronic disease populations. METHODS: A mixed methods study including semi-structured interviews and a questionnaire was conducted. A purposive sample was developed of health care organizations which were recognized as exemplars for PHRs and were high performers in national patient satisfaction surveys (H-CAHPS or CAHPS). Within each organization, participants were health IT leaders or those managing high-risk or chronic disease populations. RESULTS: Interviews were conducted with 30 informants and completed questionnaires were received from 16 organizations (84% response rate). Most PHRs allowed patients to access health records and educational material, message their provider, renew prescriptions and request appointments. Patient generated data was increasingly being sought and combined with messaging, resulted in greater understanding of patient health and functioning outside of the clinic visit. However for chronic disease populations, there was little targeted involvement in PHR design and few tools to help interpret and manage their conditions beyond those offered for all. The PHR was largely uncoupled from high risk population management interventions and no clear framework for future PHR development emerged. CONCLUSION: This technology is currently underutilized and represents a major opportunity given the potential benefits of patient engagement and shared decision making. A coherent patient-centric PHR design and evaluation strategy is required to realize its potential and maximize this natural hub for multidisciplinary care co-ordination.

Relationship between documentation method and quality of chronic disease visit notes.

OBJECTIVE: To assses the relationship between methods of documenting visit notes and note quality for primary care providers (PCPs) and specialists, and to determine the factors that contribute to higher quality notes for two chronic diseases. METHODS: Retrospective chart review of visit notes at two academic medical centers. Two physicians rated the subjective quality of content areas of the note (vital signs, medications, lifestyle, labs, symptoms, assessment & plan), overall quality, and completed the 9 item Physician Documentation Quality Instrument (PDQI-9). We evaluated quality ratings in relation to the primary method of documentation (templates, free-form or dictation) for both PCPs and specialists. A one factor analysis of variance test was used to examine differences in mean quality scores among the methods. RESULTS: A total of 112 physicians, 71 primary care physicians (PCP) and 41 specialists, wrote 240 notes. For specialists, templated notes had the highest overall quality scores (p≤0.001) while for PCPs, there was no statistically significant difference in overall quality score. For PCPs, free form received higher quality ratings on vital signs (p = 0.01), labs (p = 0.002), and lifestyle (p = 0.002) than other methods; templated notes had a higher rating on medications (p≤0.001). For specialists, templated notes received higher ratings on vital signs, labs, lifestyle and medications (p = 0.001). DISCUSSION: There was no significant difference in subjective quality of visit notes written using free-form documentation, dictation or templates for PCPs. The subjective quality rating of templated notes was higher than that of dictated notes for specialists. CONCLUSION: As there is wide variation in physician documentation methods, and no significant difference in note quality between methods, recommending one approach for all physicians may not deliver optimal results.

Evaluation of a Korean version of a tool for assessing the incorporation of human factors into a medication-related decision support system: the I-MeDeSA.

OBJECTIVE: The Instrument for Evaluating Human-Factor Principles in Medication-Related Decision Support Alerts (I-MeDeSA) was developed recently in the US with a view towards improving considerations of human-factor principles when designing alerts for clinical decision support (CDS) systems. This study evaluated the generalizability of this tool, in cooperation with its authors, across cultures by applying it to a Korean system. We also examined opportunities to promote user acceptance of the system. METHODS: We developed a Korean version of the I-MeDeSA (K-I-MeDeSA) and used it to evaluate drug-drug interaction alerts in a large academic tertiary hospital in Seoul. We involved four reviewers (A, B, C, and D). Two (A and B) conducted the initial independent scoring, while the other two (C and D) performed a final review and assessed feedback from the initial reviewers. The obtained scores were compared with those from 13 previously reported CDS systems. The feedback was summarized qualitatively. RESULTS: The translation of the I-MeDeSA had excellent interrater agreement in terms of face validity (scale-level content validity index = 0.95). The system's K-I-MeDeSA score was 10 out of 26, with a good agreement between reviewers (κ = 0.77), which showed a lack of human-factor considerations. The reviewers readily identified two of the nine principles that needed primary improvement: prioritization and text-based information. The reviewers also expressed difficulty judging the following four principles: alarm philosophy, visibility, color, and learnability and confusability. CONCLUSION: The K-I-MeDeSA was semantically and operationally equivalent to the original tool. Only minor cultural problems were identified, leading the reviewers to suggest the need for clarification of certain words plus a more detailed description of the tool's rationale and exemplars. Further evaluation is needed to empirically assess whether the implementation of changes in an electronic health record system could improve the adoption of CDS alerts.

Increasing patient engagement: patients' responses to viewing problem lists online.

OBJECTIVE: To characterize the opinions, emotions, and actions taken by patients who viewed their electronic problem list via an online personal health record (PHR). MATERIALS AND METHODS: An online survey of patients who viewed their problem lists, as maintained by their healthcare provider, in a web-based PHR linked to an electronic health record for the first time. RESULTS: A total 3,649 patients completed the survey, yielding a response rate of 42.1%. Patient attitudes towards the problem list function were positive overall, with 90.4% rating it at least somewhat useful and 86.7% reporting they would probably or definitely use it again. Nearly half (45.6%) of patients identified at least one major or minor problem missing from their list. After viewing the list, 56.1% of patients reported taking at least one action in response, with 32.4% of patients reporting that they researched a condition on the Internet, 18.3% reported that they contacted their healthcare provider and 16.7% reported changing or planning to change a health behavior (patients could report multiple actions). 64.7% of patients reported feeling at least somewhat happy while viewing their problem list, though others reported feeling sad (30.4%), worried (35.7%) or scared (23.8%) (patients could report multiple emotions). A smaller number of patients reported feeling angry (16.6%) or ashamed (14.3%). Patients who experienced an emotional response were more likely to take action. CONCLUSION: Overall, patients found the ability to view their problem lists very useful and took action in response to the information. However, some had negative emotions. More research is needed into optimal strategies for supporting patients receiving this information.

eHealth in North America.

OBJECTIVE: The overall objective of this paper is to provide an overview of the current status of electronic health record (EHR) adoption and implementation in Canada and the United States. METHODS: A review and synthesis of the empirical and grey literature about adoption of electronic health records in Canada and the United States was undertaken. RESULTS: Both Canada and the United States have experienced increases in their adoption rates. More specifically, 2012 adoption statistics reveal that the electronic medical record adoption rate in the United States is 69% and in Canada it is 57%. Significant investment by both governments has increased adoption of electronic records across North America. CONCLUSIONS: In the United States and Canada there has been a significant rise in the adoption of electronic records by health professionals with the aid of national government incentive programs.

Provider use of and attitudes towards an active clinical alert: a case study in decision support.

BACKGROUND: In a previous study, we reported on a successful clinical decision support (CDS) intervention designed to improve electronic problem list accuracy, but did not study variability of provider response to the intervention or provider attitudes towards it. The alert system accurately predicted missing problem list items based on health data captured in a patient's electronic medical record. OBJECTIVE: To assess provider attitudes towards a rule-based CDS alert system as well as heterogeneity of acceptance rates across providers. METHODS: We conducted a by-provider analysis of alert logs from the previous study. In addition, we assessed provider opinions of the intervention via an email survey of providers who received the alerts (n = 140). RESULTS: Although the alert acceptance rate was 38.1%, individual provider acceptance rates varied widely, with an interquartile range (IQR) of 14.8%-54.4%, and many outliers accepting none or nearly all of the alerts they received. No demographic variables, including degree, gender, age, assigned clinic, medical school or graduation year predicted acceptance rates. Providers' self-reported acceptance rate and perceived alert frequency were only moderately correlated with actual acceptance rates and alert frequency. CONCLUSIONS: Acceptance of this CDS intervention among providers was highly variable but this heterogeneity is not explained by measured demographic factors, suggesting that alert acceptance is a complex and individual phenomenon. Furthermore, providers' self-reports of their use of the CDS alerting system correlated only modestly with logged usage.

Discussion of "Attitude of physicians towards automatic alerting in computerized physician order entry systems".

With these comments on the paper "Attitude of Physicians Towards Automatic Alerting in Computerized Physician Order Entry Systems", written by Martin Jung and co-authors, with Dr. Elske Ammenwerth as senior author [1], the journal wants to stimulate a broad discussion on computerized physician order entry systems. An international group of experts have been invited by the editor of Methods to comment on this paper. Each of the invited commentaries forms one section of this paper.

Systems-based approaches to osteoporosis and fracture care: policy and research recommendations from the workgroups.

Participants in the conference selected to attend two different working group sessions. The working groups discussed different perspectives of system-based approaches to osteoporosis and fracture care. The group on postfracture case management recommended that nurse case managers be used to improve communication among patients, orthopaedic surgeons, and those providing ongoing clinical care. The hospital working group discussed the impact of and barriers to improved postfracture management in the hospital setting. The health systems group emphasized the difference between a closed system in which long-term benefits of interventions were more likely to be appreciated than in fee for service systems. The health information technology group discussed the advantages and challenges of electronic health records. The working group on consumer and provider education discussed interventions for both primary and secondary prevention of fractures. Recommendations were produced by most groups for improving postfracture care.

Prevalence of adverse events in the hospitals of five Latin American countries: results of the 'Iberoamerican Study of Adverse Events' (IBEAS).

BACKGROUND: Interest in patient safety (PS) is growing exponentially, fuelled by epidemiological research unveiling the extent of unsafe care. However, there is little information about the frequency of harm in developing and transitional countries. To address this issue, the authors performed a study known as the Iberoamerican Adverse Event Study, through a collaborative between the governments of Argentina, Colombia, Costa Rica, Mexico and Peru, the Spanish Ministry of Health, Social Policy and Equality, the Pan American Health Organization and the WHO Patient Safety. METHODS: The study used a cross-sectional design, involving 58 hospitals in the five Latin American countries, to measure the point prevalence of patients presenting an adverse event (AE) on the day of observation. All inpatients at the time of the study were included. RESULTS: A total of 11 379 inpatients were surveyed. Of these, 1191 had at least one AE that the reviewer judged to be related to the care received rather than to the underlying conditions. The estimated point prevalence rate was 10.5% (95% CI 9.91 to 11.04), with more than 28% of AE causing disability and another 6% associated with the death of the patient. Almost 60% of AE were considered preventable. CONCLUSIONS: The high rate of prevalent AE found suggests that PS may represent an important public-health issue in the participating hospitals. While new studies may be needed to confirm these results, these may already be useful to inspire new PS-improvement policies in those settings.

Towards meaningful medication-related clinical decision support: recommendations for an initial implementation.

SUMMARY: Clinical decision support (CDS) can improve safety, quality, and cost-effectiveness of patient care, especially when implemented in computerized provider order entry (CPOE) applications. Medication-related decision support logic forms a large component of the CDS logic in any CPOE system. However, organizations wishing to implement CDS must either purchase the computable clinical content or develop it themselves. Content provided by vendors does not always meet local expectations. Most organizations lack the resources to customize the clinical content and the expertise to implement it effectively. In this paper, we describe the recommendations of a national expert panel on two basic medication-related CDS areas, specifically, drug-drug interaction (DDI) checking and duplicate therapy checking. The goals of this study were to define a starter set of medication-related alerts that healthcare organizations can implement in their clinical information systems. We also draw on the experiences of diverse institutions to highlight the realities of implementing medication decision support. These findings represent the experiences of institutions with a long history in the domain of medication decision support, and the hope is that this guidance may improve the feasibility and efficiency CDS adoption across healthcare settings.

Measures of patient safety in developing and emerging countries: a review of the literature.

CONTEXT: The World Alliance for Patient Safety was formed to accelerate worldwide research progress towards measurably improving patient safety. Although rates of adverse events have been studied in industrialised countries, little is known about the rates of adverse events in developing and emerging countries. PURPOSE: To review the literature on patient safety issues in developing and emerging countries, to identify patient safety measures presently used in these countries and to propose a method of measurably improving patient safety measurement in these countries. METHODS: Using the Medline database for 1998 to 2007, we identified and reviewed 23 English-language articles that examined patient safety measurement in developing and emerging countries. Results Our review included 12 studies that prospectively measured patient safety and 11 studies that retrospectively measured safety. Two studies used measures of structure and the remaining used process measures, outcome measures or both. Whereas a few studies used surveys or direct observation, most studies used chart audits to measure patient safety. Most studies addressed safety at a single facility. CONCLUSIONS: Investigation of patient safety in developing and emerging countries has been infrequent and limited in scope. Establishing fundamental safe patient practices, integrating those processes into routine health services delivery and developing patients' expectations that such processes be present are necessary prerequisites to measuring and monitoring progress towards safe patient care in emerging and developing countries.

Patient safety research: an overview of the global evidence.

BACKGROUND: Unsafe medical care may cause substantial morbidity and mortality globally, despite imprecise estimates of the magnitude of the problem. To better understand the extent and nature of the problem of unsafe care, the WHO World Alliance for Patient Safety commissioned an overview of the world's literature on patient safety research. METHODS: Major patient safety topics were identified through a consultative and investigative process and were categorised into the framework of structure, process and outcomes of unsafe care. Lead experts examined current evidence and identified major knowledge gaps relating to topics in developing, transitional and developed nations. The report was reviewed by internal and external experts and underwent improvements based on the feedback. FINDINGS: Twenty-three major patient safety topics were examined. Much of the evidence of the outcomes of unsafe care is from developed nations, where prevalence studies demonstrate that between 3% and 16% of hospitalised patients suffer harm from medical care. Data from transitional and developing countries also suggest substantial harm from medical care. However, considerable gaps in knowledge about the structural and process factors that underlie unsafe care globally make solutions difficult to identify, especially in resource-poor settings. INTERPRETATION: Harm from medical care appears to pose a substantial burden to the world's population. However, much of the evidence base comes from developed nations. Understanding the scope of and solutions for unsafe care for the rest of the world is a critical component of delivering safe, effective care to all of the world's citizens.