FOR APLUS WRITER ONLY !

Increasing medication error reporting rates while reducing harm through simultaneous cultural and system-level interventions in an intensive care unit

Katherine M Abstoss, 1 Brenda E Shaw,

2 Tonie A Owens,

2 Julie L Juno,

2

Elaine L Commiskey, 3 Matthew F Niedner

4

ABSTRACT Objective: This study analyses patterns in reporting rates of medication errors, rates of medication errors

with harm, and responses to the Safety Attitudes

Questionnaire (SAQ), all in the context of four cultural

and three system-level interventions for medication

safety in an intensive care unit.

Methods: Over a period of 2.5 years (May 2007 to November 2009), seven overlapping interventions to

improve medication safety and reporting were

implemented: a poster tracking ‘days since last

medication error resulting in harm’, a continuous

slideshow showing performance metrics in the staff

lounge, multiple didactic curricula, unit-wide emails

summarising medication errors, computerised

physician order entry, introduction of unit-based

pharmacy technicians for medication delivery, and

patient safety report form streamlining. The reporting

rate of medication errors and errors with harm were

analysed over time using statistical process control.

SAQ responses were collected annually.

Results: Subsequent to the interventions, the reporting rate of medication errors increased 25%, from an

average of 3.16 to 3.95 per 10 000 doses dispensed

(p<0.09), while the rate of medication errors resulting in

harm decreased 71%, from an average of 0.56 to 0.16

per 10 000 doses dispensed (p<0.01). The SAQ showed

improvement in all 13 survey items related to medication

safety, five of which were significant (p<0.05).

Conclusion: Actively developing a transparent and positive safety culture at the unit level can improve

medication safety. System-level mechanisms to

promote medication safety are likely important factors

that enable safety culture to translate into better

outcomes, but may be independently ineffective in the

face of poor safety culture.

INTRODUCTION

In 2000, the landmark Institute of Medicine report To err is human: building a better health

system made plain the alarmingly high rate of medication errors in the United States, citing that medication errors were estimated to account for approximately 7000 patient deaths annually.1 Improving patient safety in all regards has become an increasing imperative in healthcare over the past decade, and many efforts have been aimed at better measuring and reducing medication-related harm. Medication errors are underreported for

many reasons, including: fear of reprisal, the concern of lawsuits, time constraints, uncer- tainty of which incidents to report, concerns of implicating others and lack of feedback and evidence that information was valued and used for system change.2e4 Traditionally, the focus was on the clinician’s error, and blame was followed by punishment.5 However, punitive responses have led to errors being hidden, preventing the recognition, analysis and correction of the root causes and systemic problems.1 5 6 Effective reporting of errors is critical to discovering process defects in complex systems, and transparent, non-puni- tive dissemination of findings is crucial for organisational learning.7 8

While implementing error-proofing concepts for human factors is conceivable and well published, effective strategies for improving the safety culture are more complex and poorly understood. Safety culture can be defined as ‘the product of individual and group values, attitudes, perceptions, competencies, and patterns of behaviour that determine the commitment to, and the style and proficiency of, an orga- nisation’s health and safety management’.9

Huang et al associated poor frontline perceptions of management with hospital

1Department of Health Management and Policy, School of Public Health, University of Michigan, Ann Arbor, Michigan, USA 2CS Mott Children’s Hospital, Pediatric Intensive Care Unit Nursing, University of Michigan, Ann Arbor, Michigan, USA 3Health System Risk Management, University of Michigan, Ann Arbor, Michigan, USA 4Division of Pediatric Critical Care Medicine, University of Michigan, Ann Arbor, Michigan, USA

Correspondence to Katherine M Abstoss, Department of Health Management and Policy, School of Public Health, University of Michigan, 1113 Olivia Avenue, Ann Arbor, MI 48104, USA; [email protected]

Accepted 19 April 2011 Published Online First 20 June 2011

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mortality rates, and low safety culture measures with increased length of stay.10 And while culture in the microcosm of a medical unit is partly an emergent phenomenon, leaders also shape a unit’s culture. Leaders communicate what they feel is important through symbolic actions, rewards and punishments. If leaders encourage a free and open environment of information flow, incident reporting will increase.11 As individuals ‘buy into’ the mission of patient safety and quality improvement, a sense of ownership leads to empowerment.11 Indeed, contrary to the thought that a high error reporting rate is a marker of less safe care, it may be an indicator of positive safety culture that is associated with less harm.2 However, concomitant measures of errors, harm, and culture are necessary to discern such phenomena. A system designed for safety anticipates errors, designs

processes with human factors and safety in mind, while creating a culture that encourages and rewards error reporting and includes team members in developing safeguards for error prevention.12 13 While numerous structural and system changes have been proven effec- tive at reducing medication errors, the efforts reported herein focus more on the effects of safety culture trans- formation, and the combination of culture with system. This analysis was undertaken to better understand the impact of both system-level and safety culture strategies deployed in our paediatric intensive care unit (PICU) on medication error reporting and harm. We hypothesised that both general and specific cultural interventions would result in significant changes of safety culture measures that would be temporally associated with unit- level performance improvements in patient safetyd namely increased medication error reporting and decreased medication harm.

METHODS

The University of Michigan’s C.S. Mott Children’s Hospital PICU tracks medication errors through a number of mechanisms, but primarily by voluntary reporting through a web-based portal that is secure and optionally anonymous. All submissions are systemati- cally categorised in terms of harm. Determinations of harm, including whether the harm was preventable, likelihood of recurrence, and strategies for improve- ment are all optionally and preliminarily adjudicated by the individual filing the report, then formally reviewed and adjudicated by risk management, the unit level nursing leadership, pharmacists (when indicated), and selectively by multidisciplinary review at a monthly morbidity and mortality conference. For the purposes of this analysis, medication errors include all reported errors (including near misses), categorised A through I

by the National Coordinating Council for Medication Error Reporting and Prevention; medication errors resulting in harm is the subset of all reported errors with a harm rating greater than ‘temporary and insig- nificant’ or category E or greater.14 Not all errors result in harm (eg, a near miss), and harm may be due to an error-free intervention (eg, an adverse drug reaction). In this analysis, medication errors resulting in harm were defined by the overlap between medication error and adverse drug reaction, and were therefore a discreet subset of all reported medication-related errors.15 16 Harm generally reflected either patient intolerance (eg, pain or agitation) or a medical response to the harm (eg, fluid bolus for low blood pressure). Medication dose dispensation in the PICU is captured though electronic pharmacy records, yielding denominators to calculate rates of error reporting and harm. The rates of all reported medication errors and medication errors resulting in harm are plotted on control charts and prospectively monitored by the PICU quality and safety committee. The primary outcome measure of this analysis is medication errors resulting in harm, with secondary process measures of medication error reporting rates and 13 relevant culture measures from the Safety Attitudes Questionnaire (SAQ). The University of Michigan Institutional Review Board screened this study and waived formal oversight, as it was deemed a retrospective analysis of prospective quality and management work devoid of subject-level data. On an annual basis, the SAQ is administered in the

PICU as part of a routine unit assessment. The SAQ, a psychometrically validated instrument, includes 64 questions that capture the attitudes and perspectives of staff on specific safety issues at a granular level. Thirteen of the elements are relatable to medication error or reporting safety concerns.9

From May 2007 through November 2009, the PICU implemented seven overlapping interventions to promote, among other things, the reporting of medica- tion errors. Interventions were of two broad categories: interventions to improve the safety culture and team- work around medications; and system or structural interventions to better enable safe medication adminis- tration and ease of error reporting. Many of the inter- ventions arguably had both systemic and cultural aspects, but were categorised based on the dominant purpose of the intervention. None of the interventions were level I error proofing methods, but all were expected to reduce the likelihood of medication error occurrences, propa- gation, or repetition. Interventions emerged from stan- dard, institutional management processes (eg, committee meetings where patient safety is discussed). Intervention selection and timing were based on

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a combination of management judgement, readiness of staff, and available resources. The interventions are outlined below, with their implementation dates listed in table 1.

Culture interventions Poster tracking ‘Days since last medication error with harm’

The PICU displays a poster in the unit’s staff lounge that historically tracked multiple quality-related adverse events, including nosocomial infection occurrences, unplanned readmissions, and unplanned extubations. In November 2008, fields were added to this poster to relate medication errors resulting in harm to patients. In contrast to calculated error rates preferred by manage- ment, the poster expresses performance metrics in a way that is intuitive to the staff, including ‘days since’ the last adverse event, the record number of days with no adverse events, the average number of days between events and the number of events in the last 12 months. The metrics were purposely chosen to reflect time periods and measurements that ‘make sense’ to the frontline staff. Staff members refer to the poster in order to promote a sort of competition or personal challenge, ‘How many days since? What record do we need to beat?’ The poster serves as a visual reminder that harmful events happen to specific people in real timedthe data are not just audited performance metrics that are inattentively collected and reported.

Quality improvement channel

The ‘QI channel’, which began in January 2009, plays a cycling slideshow on a large screen television in the PICU staff room. The content includes performance metrics, adverse event lessons learnt and action plans, policy updates, educational pearls regarding the science of quality improvement and patient safety, social

announcements, humour and inspiration. It was created to maintain dynamic and contemporary communication with staff, in a format that recognises the challenges of running at 24-7-365 unit. The ‘QI channel’ continues to provide a way to continuously communicate a diverse array of information, using a venue that is palatable, interesting, continuous and difficult to ignore.

Quality improvement curriculum

The PICU organised three didactic ‘mini-symposia’ targeting frontline healthcare workers with content focused on healthcare safety and quality improvement, including content on medication safety and reporting. Sessions were held in January 2008, September 2008, and September 2009. In total, more than 40 h of continuing education were provided within the PICU over 20 months. The intent was to provide frontline workers with information on patient safety and quality improvement, while improving transparency in the unit. Specific themes contained in the sessions included medication safety (eg, electronic order entry), trans- parency (eg, the value of learning from errors), psychological safety (eg, non-punitive leadership response to error), and communication strategies (eg, closed loop communication).

Medication error emails

The PICU sends periodic emails to its staff summarising recent medication error reports, including near misses and those resulting in harm. The first email was distributed in January 2009. The emails explain the event, lessons learnt, and any resultant practice changes, without relating the names of the patients nor the clinician involved in the error. The emails also praise individual staff that identify and address potential errors before they occur, giving public recognition and thanks for their efforts as safety champions. The emails are written in a positive and non-punitive light, in order to encourage self-reporting of errors, shared awareness of errors, and to disseminate these opportunities for improvement widely.

System interventions Computerised physician order entry

The University of Michigan Health System implemented a computerised physician order entry (CPOE) system, with the PICU going live in May 2007. CPOE allows clinicians to enter treatment instructions for patients electronically in a manner that theoretically increases efficiency in communication, reduces errors related to handwriting or transcription, provides automated error- checking, and simplifies inventory. Much research has demonstrated how CPOE can improve medication safety.17

Table 1 Cultural and systemic interventions to increase medication error reporting

Dates of note

5/2007 Computerized physician order entry (CPOE) initiated in PICU

10/2007 PICU Medication Manager program commenced

1/2008 Quality improvement curriculum I* 9/2008 Quality improvement curriculum II* 9/2008 Patient safety report form revised 11/2008 ‘Days since’ poster addition reflects

medication errors with harm* 1/2009 QI Channel commenced* 2/2009 Medication error emails commenced* 9/2009 Quality improvement curriculum III* 11/2009 Patient safety report form revised

*Denotes cultural interventions.

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PICU medication manager program

C.S. Mott Children’s Hospital initiated a Medication Manager program in the PICU in October 2007, as described in detail elsewhere.18 The Medication Managers are pharmacy technicians who provide the following services: delivering medications to the bedside, managing prioritisation of medication delivery, streamlining communication related to medication needs, restocking of automated medication dispensers, refilling drugs and replacing missing medications, monitoring drip rates and volumes, monitoring extra- corporeal medication/fluid supplies and rates, communicating with the pharmacy, performing hourly medication runs and in-between hour STAT runs, removing discontinued medications from the bedside/ unit, controlling insulin storage, and transferring medications to other patient care areas. By internal metrics, the use of Medication Managers in the PICU improved pharmacy and nursing communication, increased nurse’s time with the patient, and reduced medication waste, but no signal was appreciated regarding impact on medication errors.

Patient safety report form revisions

In September 2008, several changes were made to the patient safety report form in order to make reporting easier. To assist reporters in locating the online form easily, a link to the portal was added to the intranet homepage. The form title was clarified to ‘patient safety incident’ to focus reports from the patient perspective and incidents instead of persons. The link to the form was changed to route directly to the login page, elimi- nating the need to navigate the Risk Management website. In addition, the form itself was revised to reduce the number of mandatory fields and eliminate entire non-mandatory screens. The form was further revised in November 2009, when the multi-page form was consoli- dated into a single quick submission form with all required fields in a single area. These changes were in keeping with visual space management, lean and human factors engineering, and simply making it easy to do the right thing.

Statistical analysis Over the time period July 2006 to May 2010, the medi- cation error and medication error with harm reporting rates were plotted regularly on a prospective statistical control chart or u-chart (figure 1).19 Medication errors resulting in harm were established as the outcome measure, and the reporting rates and the culture measures (SAQ) as process measures. Statistical process control was the preferred method for real-time insight into the data, and the natural break points were identi- fied through special cause variation using the four

conventional rules, at which point mean lines were adjusted.20 In addition, the number of exposures (ie, medications dispensed), between medication errors with harm was plotted on a chart for rare events or g-chart, to better understand the time at which the long error-free interval became significant. For the purposes of this analysis, the before and after time periods were split in February 2009, as this was the point when all new inter- ventions had been initiated. One-sided t-tests were used

Figure 1 Unit level medication error reporting rate, medication errors with harm rate, and medication exposures between reported harmful events. The three control charts for the pediatric intensive care unit data share the same timeline. The only dates shown correspond to the start and end of the analysis, as well as the months during which interventions occurred, corresponding to table 1. Asterisked dates correspond to culture interventions. All three control charts show special cause variation (points where mean line is adjusted), with increased medication error reporting, decreased medication-related harm (a subset of the former), and more exposures to dispensed medication between reported harmful events (revealing the earliest time when special cause variation occurred).

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for SAQ data analyses and retrospectively on medication error rates to generate more familiar p values; statistical significance was defined as a p<0.05 without correction for multiple analyses.

RESULTS

Over the study period, the overall rate at which medi- cation errors were reported increased, while the rate at which medication errors with harm occurred decreased. Figure 1 shows the number of medication error reports per 10 000 doses increasing from July 2006 to May 2010, with special cause variation occurring in December 2009. At the same time, the medication errors with harm per 10 000 doses that were reported decreased, reaching special cause variation in November 2008, and again in July 2009. Lastly, the number of exposures between errors reported with harm increased over the period, crossing the control limit around November 2009, indicating special cause variation. Traditional statistical analysis of the data was

performed comparing the data before and after February 2009, when the last new intervention began. The reported errors resulting in harm decreased from an average of 0.56 to 0.16 events per 10 000 doses, a 71% reduction (p<0.01). The overall error reporting rate during the same period increased from an average of 3.16 to 3.95 reports per 10 000 doses, an increase of 25% (p<0.09). Errors during the study period are categorised

by the National Coordinating Council for Medication Error Reporting and Prevention taxonomy in table 2. Contextual control data were gathered to better

characterise the relative impact of some of the system interventions. Because the PICU is a unit within a chil- dren’s hospital within a health system, both the data for the health system as a whole, and the rest of the paedi- atric hospital (excluding the PICU) were used as control data to compare with the PICU results. Both CPOE implementation and patient safety report streamlining were system wide, so a reporting rate for all inpatient incidents was plotted on a control chart, annotated with these interventions (figure 2). After CPOE imple- mentation, patient safety reports decreased in frequency, and streamlining the reporting process was not tempo- rally associated with any increased reporting. Specifically looking at safety reports filed for medication events within the children’s hospital (excluding PICU), a similar pattern was observed (figure 3). Finally, safety reports filed for medication-related harm within the children’s hospital (excluding the PICU) were plotted, and showed a fairly flat rate across the entire period of analysis (figure 4). The SAQ was administered annually, and selected line

item results from April 2007 (n¼108, 88% response rate) and August 2009 (n¼85, 90% response rate) are summarised in table 3. During this interval, 10 measures of safety and ease of incident reporting increased, while three measures of difficulty or hesitation in reporting

Table 2 Medication error reports categorised by the National Coordinating Council for Medication Error Reporting and Prevention Taxonomy14

7/2006 to 2/2009 3/2009 to 5/2010

Summary Total medication error reports 128 75 Average reports per month 4.0 5.0 Reports per 10 000 doses dispensed 3.12 4.08

No harm AdCircumstances or events that have the capacity to cause error 6% 7% BdAn error occurred but the error did not reach the patient; ‘near miss’ 10% 7% CdAn error occurred that reached the patient, but did not cause patient harm

42% 47%

DdAn error occurred that reached the patient and required monitoring to confirm that it resulted in no harm to the patient and/or required intervention to preclude harm

35% 36%

Harm EdAn error occurred that may have contributed to or resulted in temporary harm to the patient and required intervention*

8% 4%

FdAn error occurred that may have contributed to or resulted in temporary harm to the patient and required initial or prolonged hospitalization*

0% 0%

GdAn error occurred that may have contributed to or resulted in permanent patient harm*

0% 0%

HdAn error occurred that required intervention necessary to sustain life* 0% 0% IdAn error occurred that may have contributed to or resulted in the patient’s death*

0% 0%

*Indicates errors that the UMHS PICU categorises as errors resulting in harm.

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decreased, five of which were statistically significant changes. In addition to the SAQ line items, we also derived the two major domains pertaining to teamwork and safety climate. Subsequent to 2007, both domains improved; teamwork climate increased from 52.8% to 71.8% agreement (p¼0.003), while safety climate increased from 54.6% to 63.4% agreement (p¼0.127).

DISCUSSION

To our knowledge, this is the first analysis associating unit-level interventions targeting safety culture with increased medication error reporting and decreased medication-related harm. Although multiple system-level changes occurred in 2007, it was only after a cluster of culture interventions in 2008e2009 that medication error reporting increased while errors with harm decreased. Given the multiple stepwise uncontrolled quality improvement efforts targeting medication safety

in the PICU, it is difficult to determine which individual interventions had what attributable impactdonly that overall trends in medication safety improved with concomitant improvements in staff attitudes towards patient safety and error reporting. From a temporal perspective, the series of system-level interventions in 2007 did not appear to be sufficient to create the changes observed in measured outcomes of medication safety, especially when viewed in the context of institution-wide data. While the PICU’s reporting rate went up and harm went down, institutional reporting rates went down, and harm rates were flat. While confounding factors exist, two main lines of argument could be used to explain the findings: system-level interventions are not effective in a unit with poor safety culture; and/or improving safety culture can have a more substantial impact on safety outcomes than many system-level interventions. Yet these two are not mutually exclusive because an improved safety culture may only have achieved leverage in a system

Figure 2 Institutional rate for all inpatient safety reports. The safety reporting rate throughout the healthcare system dropped sequentially, meeting special cause variation during or after each related system-wide intervention annotated.

Figure 3 Children’s hospital rate for medication safety reports, excluding the pediatric intensive care unit. The reporting rate for medication-related safety throughout the children’s hospital- within-a-hospital dropped, meeting special cause variation during implementation of computerised physician order entry, but demonstrating only common cause variation after streamlining the reporting system.

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that allowed or facilitated it. Piecemeal approaches to cultural and system-level interventions may not have the same effect as an integrated approach.

Factors that have been described to improve voluntary reporting include creating a supportive environment, establishing anonymity, using clear, web-based forms and

Figure 4 Children’s hospital rate for medication safety reports associated with harm, excluding the pediatric intensive care unit. The reporting rate for medication- related harm throughout the children’s hospital-within-a- hospital only demonstrated common cause variation during the interval of analysis.

Table 3 Differences in responses to Safety Attitudes Questionnaire pre intervention and post intervention

Questionnaire line item

% Agree or strongly agree %

p2007 2009 Change

If necessary, I know how to report errors that happen in this ICU

89.6 98.8 10.3 0.003*

I am encouraged by my colleagues to report any patient safety concerns I may have

85.2 88.2 3.6 0.267

Medical errorsy are handled appropriately in this ICU 76.6 83.3 8.7 0.123

Information obtained through incident reports is used to make patient care safer in this ICU

79.2 83.3 5.2 0.243

Personnel are not punished for errors reported through incident reports

60.4 73.5 21.7 0.020*

The culture in this ICU makes it easy to learn from the errors of others

63.9 75.3 17.9 0.042*

I have seen others make errors that had the potential to harm patients

50.5 56.0 10.9 0.222

I have made errors that had the potential to harm patients 37.7 51.2 35.7 0.028*

Error reporting is rewarded in this ICU 10.5 25.3 141.5 0.003*

A confidential reporting system that documents medical incidents is helpful for improving patient safety

84.1 89.4 6.3 0.144

In this ICU, it is difficult to discuss errorsz 17.8 12.9 27.1 0.185

In this ICU, it is difficult to speak up if I perceive a problem with patient carez

20.6 14.1 31.3 0.125

I may hesitate to use a reporting system for medical incidents because I am concerned about being identifiedz

17.1 10.7 37.5 0.080

In 2007, n¼108; in 2009, n¼85. *p Values are statistically significant at the 95% level, using a one-sided t test.

yMedical error defined as any mistake in the delivery of care, by any healthcare professional, regardless of outcome. zNegatively worded question for which a low score is desirable.

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providing feedback to reports, all of which we have worked to implement.21 Furthermore, the error reporting rate was an important outcome measure of meaningful engagement in safety practices (such as disclosure and transparency) in the PICU, and an important balancing measure to ensure that less measured harm was not simply a manifestation of decreased reporting. While the number of medication errors reported increased in the study period, it is not clear whether the actual number of errors, including near misses, changed. It is likely that the true frequency of medication errors remained fairly static, but that staff members were more likely to recognise and report them with an understanding that their reports are valued and that transparency is rewarded. This was reflected by significant improvements in questions from the SAQ such as ‘Error reporting is rewarded in this ICU’ and ‘Personnel are not punished for errors reported through incident reports’. The sense of teamwork related to error reporting improved as staff felt supported by colleagues in reporting errors and believed they were better enabled to learn from each others’ errors. The staff felt reports were valued as the ‘Information obtained through incident reports is used to make patient care safer in this ICU’ metric improved. The questionnaire also showed educational and system-level improvements, demonstrated by the increase in the staff’s comfort level in knowing how to report errors. While Hutchinson et al demonstrated a positive asso-

ciation between incident reporting rates and measures of safety culture when comparing institutions;2 we demon- strate that changing the safety culture within a specific unit may lead to improved reporting and reduced harm for a specific incident type in a relatively short time period. The seemingly paradoxical discord between increased reporting and decreased harm is more likely reflective of a preferable state where unit leadership and frontline alike have greater awareness of risks emerging from a complex system and are therefore better able to prevent or mitigate untoward effects on patients.2 10

These findings further highlight that safety culture is largely a unit-level phenomenon responsive to unit-level interventions, and invite healthcare professionals to identify effective approaches to actively improve safety culture in their local care areas. This analysis illustrates an example of ‘interventional anthropology’, improving clinical and operational outcomes by improving teamwork and safety culture.22e25

Much research has demonstrated how system-level interventions, such as CPOE and ease of reporting, can improve medication safety.17 However, CPOE and other human factors engineering interventions have also been implemented without appreciable improvementsdand occasionally to apparent detriment.26 27 The PICU data

do not show an impact on medication safety either way that is temporally related to several of these system-level interventions. It is after interventions focused on changing the unit’s culture that a favourable impact on medication safety emerges. While improving the system may be important to achieve higher medication safety performance in some units, it may also be insufficient in the context of a healthcare team struggling with safety and teamwork issues. Realistic evaluation, where leaders seek to understand how processes operate in a specific context, may reveal that the area of greatest leverage on medication safety is the safety culture instead of specific structures or processes within the system.28 Indeed, the substantial improvements in medication safety and SAQ scores in the PICU seem to support the old business adage that ‘culture eats strategy for lunch.’ There are important limitations to note in this anal-

ysis. First, voluntary medication error reporting is imperfect in capturing all events and types of medication errors. However, in this case, the proportion of medica- tion errors resulting in harm (category E or greater) is consistent with a previous study using trigger tools to identify medication errors through chart review.29

Because it is the most common and economical method used, finding ways to optimise voluntary medication error reporting is of practical value; further, each system for detecting medication-related harm has strengths and weaknesses.30 31 While no ideal control data exist in this unit-based longitudinal analysis, reporting and harm patterns within the institution and children’s hospital provide some context in which to interpret institution- wide systems interventions, as well as to isolate the effects of unit-level culture interventions. It should be noted that these comparative data included all safety reports and all reported harm, not only those relating to errors. Additionally, the multiple overlapping interventions were undertaken in a prospective quality improvement manner, without waiting for signal or stabilisation in measures before further safety strategies were deployed. This confounds any ability to assign discreet attribut- ability and poses limitations to the simple before versus after analyses presented. Therefore data are presented in the format used prospectively by the improvement teamdstatistical process control with annotated control charts.

CONCLUSION

The data reveal an association between a unit’s safety culture and medication safety measures. Specifically, improved cultural measures are paralleled by higher medication error reporting but lower medication-related harm. Further, medication error rates and harm appear to be responsive to interventions targeting safety culture

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over a fairly short timeframe. Actively developing a transparent and positive safety culture at the unit level can measurably improve medication safety. System-level mechanisms to promote medication safety are likely important factors that enable positive safety culture to translate into better outcomes, but may be ineffective by themselves in the face of poor safety culture. Methods described herein provide examples that could be adapted to other units or hospital settings.

Acknowledgements The authorship gratefully acknowledges the PICU frontline staff for their 24-7-365 hard work and dedication, and for achieving the results we proudly present in this manuscript. We also would like to thank Todd Benner (University of Michigan Health System, Medical Center Information Technology Applications Programmer) for providing us with the pharmaceutical data to run our analysis.

Competing interests None declared.

Provenance and peer review Not commissioned; externally peer reviewed.

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Original research