Abstract
Background and aim
Benchmarking is a management approach for implementing best medical practices at the lowest cost. The objectives of this study were to set achievable performance benchmarks for individual quality indicators to determine the predicted quality achievement related to better adherence, and to select optimal quality indicators for improving the quality of acute ischemic stroke care.
Methods
We analyzed data on 500,331 patients diagnosed with acute ischemic stroke who were treated at 518 hospitals in China from January 2011 to May 2017. The primary outcome was independence (modified Rankin Scale score ≤2) at discharge. Data-driven achievable benchmarking used the “pared-mean” approach to set objective performance targets. Hierarchical logistic regression models were employed to evaluate the process–outcome association, as well as the predicted quality improvement if all hospitals were to operate at the benchmark level.
Results
Of the overall population, 64.01% were independent patients at discharge. The performance benchmarks were >90% for most of the quality indicators. After adjusting for patient-level and hospital-level characteristics and unifying hospital performance to the benchmark level, the quality indicators with high increase in both overall adherence rate and independence rate were thrombolytic therapy, anticoagulant therapy, venous thrombosis prophylaxis.
Conclusions
Performance targets for three acute treatments, including thrombolytic therapy, anticoagulant therapy, venous thrombosis prophylaxis, could best motivate improvements in both overall adherence rate and independence rate at discharge. The finding suggests that the above three types of acute treatment should be given priority to improve the quality of acute ischemic stroke care.
Background
Stroke is a crippling and potentially deadly condition affecting millions of people worldwide each year.1,2 Preventing stroke and improving the quality of stroke care have been global health priorities.3–5 Although new therapies are needed to meet the challenge of improving the quality of stroke care, better application of currently available therapies may offer more immediate results in terms of saving lives and improving function. The implementation of and adherence to guideline-recommended treatments form a foundation for quality improvement and may serve as a marker of quality of care. 6
Benchmarking is a management approach for implementing best medical practices at the lowest cost. 7 It provides performance targets for improvement and promotes emulation of those providers achieving “best practice.” 8 However, it is a huge challenge to ensure that guideline-recommended treatments be more widely adopted and that frontline professionals be more involved by using benchmarking processes. How do we set objective, reproducible, and attainable performance benchmarks on the way to improving the quality of stroke care? Since a complex mix of factors can influence the implementation of and the adherence to quality indicators (QIs), setting “perfect” targets for process performance is unrealistic and inappropriate. Therefore, an important goal of the benchmark setting is to aid in the spread of “excellence practices” by a few superior providers until they become “average performance” by the majority.
Although adherence to guideline-recommended treatments has been demonstrated to improve patient outcomes, the strength, magnitude, and statistical significance of the positive effects on clinical outcomes vary across individual QIs.9–11 Before the benchmark intervention, we need to speculate the net gains in quality improvement of performance benchmarks setting and identify QIs that should be prioritized in improving the quality of stroke care.
The purpose of this study was to set achievable benchmarks for a broad spectrum of QIs based on long-term medical records on stroke care practices across China and to determine the predicted quality achievement in terms of process-adjusted positive outcomes if all hospitals were to operate at the benchmark level and to select optimal QIs for improving the quality of stroke care. To predict the composite quality achievement with benchmarking, we calculated the hospital process composite performance (HPCP).
Methods
Data source
The analyses were based on data from the Medical Care Quality Management and Control System for Specific Diseases of China, an ongoing voluntary and continuous web-based registry. The diseases in the registry included stroke, heart failure, acute myocardial infarction, cesarean section, community-acquired pneumonia (adults or children), hip/knee replacement, coronary artery bypass grafting, chronic obstructive pulmonary disease, perioperative infection prevention, and perioperative prevention of deep venous thrombosis (DVT). The system was designed to collect and manage data on QIs and provide hospitals with real-time quality-of-care reports and data validation. Since 2015, a national report on the services, quality, and safety in medical care system has been published annually based on data from the system. Each QI has an explicit definition in the reports. The system collected data from secondary or tertiary hospitals in the 31 provinces, autonomous regions, and municipalities in China. It represents more than half of all hospitalizations in tertiary hospitals nationwide. For stroke, hospitals were restricted to those with emergency departments and neurological wards that admitted patients with stroke and had the capacity to administer recombinant tissue plasminogen activator (rt-PA).
Because the data were fully anonymized and used primarily for hospital care quality management, ethical approval was not required under China research governance arrangements. Individual patient consent was waived as it was determined that this study does not meet the regulatory definition of human subject research.
Case reporting process
Data were extracted from the inpatient medical records, drug charts, discharge summary, and assessment sheets. Collectors could request additional materials such as laboratory reports stored on the computer, if they were missing from the clinical record. If the information still could not be found, it was taken as real missing data. The information collected by the system included baseline demographic characteristics, diagnostic testing, detailed medication history, health care utilization, in-hospital outcomes, and satisfaction with hospital service quality.
Patients with acute ischemic stroke (AIS) were diagnosed by the attending physician. Collectors identified the target patients from medical records according to the International Classification of Diseases version 10, diagnosis codes. Patients with other cerebrovascular diseases, such as hemorrhagic stroke, transient ischemic attack, cerebral venous sinus thrombosis, or non-cerebrovascular diseases, were not reported. Eligible record IDs were loaded into a Microsoft Excel spreadsheet and were arranged randomly and then selected consecutively. The proportion of cases selected for data reporting should not be less than 20%. The collectors were required to complete the data reporting at the end of each month.
Data reporting was conducted by trained clinical data collectors using standardized definitions. Each participating hospital appointed a surgeon or nurse responsible for (supervising) the data reporting in a secured web form. Before the online data reporting, collectors needed to read data reporting instruction carefully. The training process consisted of a web-based teaching segment for data reporting of five cases and an assessment process with system-generated 10 cases. When the inter-rater reliability reached 95% or more, the collectors could start data reporting, otherwise they would have a second teaching and assessment session. To minimize error caused by manual reporting, the system automatically collected the information on the front page of inpatient medical records from the hospital information system via a web-based data collection tool. Values that exceeded the expected ranges prompted error notification. The system also provided predefined logic checks to identify errors or illogical data entries. Besides, annual feedback on data quality problems and quality-of-care provided to all registered hospitals.
Study population
The analytical cohort of 500,331 patients treated at 518 hospitals was drawn from the 571,522 patients with a discharge diagnosis of AIS treated at 756 hospitals from 1 January 2011 to 31 May 2017. We restricted our sample to patients (1) who admitted in transfer; (2) without aberrant values, including outliers or incorrect reporting values; (3) whose age at diagnosis was older than 18 years; (4) who were hospitalized for more than one day but no longer than 120 days; and (5) who had outcome records at discharge. We also restricted our sample to hospitals (1) with at least 20 admissions overall; (2) with eligible patients for all QIs selected for this study. Because hospitals with a small number of patients were inclined to have perfect performance, which could inflate the benchmark level, hospitals with fewer than 20 admissions overall were excluded. Figure 1 presents the number of study flow diagram of the patient population. Although 238 hospitals and 71,191 patients were excluded according to the above-mentioned criteria, there was no significant difference between the included group and the excluded group (Suppl Table I and Table II).
Study flow diagram of the acute ischemic stroke patient population. N represents the number of patients deleted. HPCP: hospital process composite performance; LOS: length of stay.
QIs and outcomes
We used nine The Get With The Guidelines (GWTG)–Stroke performance measures, 12 including acute and subacute treatments. The specific definitions of QIs are listed in online-only supplementary table III. As we aimed to assess the relationship between adherence to QIs and patient in-hospital outcomes, the study excluded QIs for medication prescribed at discharge.
Acute treatments included: (1) CT/MRI scan, (2) laboratory tests, (3) electrocardiogram, (4) acute thrombolytic therapy within 3 h of symptom onset; (5) anticoagulant therapy prescribed within 48 h of admission; (6) antiplatelet therapy prescribed within 48 h of admission; (7) deep vein thrombosis prophylaxis within 48 h of admission if nonambulatory.
Subacute treatments included: (8) statins therapy during hospitalization if the low-density lipoprotein level was >2.6 mol/L; (9) dysphagia screening before any oral intake during hospitalization.
Patient outcome was assessed with the modified Rankin Scale (mRS) score at discharge. 13 Patient outcome was classified as independence (mRS score 0–2) or dependence/death (mRS score 3–6).14,15
Statistical analysis
Patient baseline characteristics for the study population were described in counts and percentages, mean, and standard deviation. Differences between independence group and dependence/death group were expressed using standardized differences. To assess hospital performance on stroke care, our primary measurement of adherence was presented as a proportion of the sum of patients who have been provided with care (numerator) to the total number of patients eligible for the care (denominator). Patients with clinical-care contraindication or lack of information on care eligibility were excluded from both the numerator and denominator. We divided patients into four groups according the number of coexisting conditions (0, 1, 2–3, ≥4) and calculated the adherence rates of individual QIs in each group.
Data-driven achievable benchmarks of care used the “pared-mean” approach to set objective performance targets.8,16 We ranked hospitals in descending order according to their performance of individual QIs. Starting with the top-ranked hospital, we cumulated each hospital’s eligible patients until a subset of patients represented at least 10% of the eligible population across all hospitals. The subset was the benchmark subset. We calculated a benchmark level for each QI based on the average performance of the subset. To predict the composite benchmark effect of all QIs, we calculated the HPCP using denominator-based weights, which was defined as the ratio of the total number of documented correct care to the sum of care opportunities for all QIs.17,18 Here, we used the same method as individual QIs to set achievable performance benchmarks for HPCP. We calculated statistical p values for the associations of the hospital structural elements with HPCP using Kruskal–Wallis H tests.
The process–outcome association was investigated using hierarchical logistic regression with patient-level and hospital-level risk factors as fixed effects and a random intercept for hospitals. The full model included the following risk factors: year and age at diagnosis, stroke subtype and severity, primary payer status, pattern of admission, comorbidities, geographic region, hospital type, hospital level, university-affiliated status, nurse-to-bed ratio, health technician-to-bed ratio, and annual outpatient volume. Hospital process performance (adherence to each QI or the HPCP) was added as a continuous predictor variable, and odds ratios (ORs) were reported per 10% increment in hospital process performance. We entered variables into the models simultaneously.
To determine the predicted quality achievement in terms of independence at discharge if all eligible hospitals were to operate at the benchmark level, we first identified hospitals in the benchmark subset. From the full covariate-adjusted hierarchical model, we considered the effect of hospital process performance as random effect. For the entire study population, we used the hierarchical model to predict the proportion of independent patients at discharge given their fixed covariates and the random effect of the benchmark subset. 19 The random effect of the benchmark subset was the weighted mean of the random effect of hospitals in the subset, which was weighted by the number of eligible patients.
Relying on the process–outcome association and using self-control method, we calculated the predicted improvement of adherence rate (IAR) and the predicted improvement of independence rate (IIR). The 95% confidence intervals (95% CI) were calculated using the bootstrap method with 1000 replications. IAR was the difference between the benchmark performance level of each QI and its observed overall adherence rate. IIR was the overall increase in the proportion of independent patients after unifying hospital performance to the benchmark level.
To mitigate against potential bias due to multiple data exclusions, we conducted a sensitivity analysis. In the sensitivity analysis, we redefined the analytical population by only excluding patients who lacked vital information on care eligibility and conducted the same analyses described above. We used SAS statistical software, Version 9.3 (SAS Institute Inc., Cary, NC, USA) for all statistical analyses.
Results
Patient characteristics
Variation in patients’ characteristics between dependent/death and independent group
mRS: modified Rankin Scale; NIHSS: National Institutes of Health Stroke Scale score; SD: standard deviation; COPD: chronic obstructive pulmonary disease.
Hospital performance on QIs
Eligible patients and adherence rates were listed in Table 2. The overall adherence differed greatly in different QIs, ranging from 22.81% of acute thrombolytic therapy to 98.75% of antiplatelet therapy. We also observed significant differences in hospital adherence to the QIs, there are three QIs with the interquartile range (IQR) of hospital adherence close to 50%: laboratory tests, electrocardiograph report, dysphagia screening. The overall composite performance on all QIs was 62.99%, and the median HPCP was 68.33% (IQR, 51.96–77.86%). Figure 2 shows the distribution of hospital composite performance by structural elements. Hospitals located in the eastern region of China and private hospitals have superior performance levels (P < 0.05).
Structural features associated with hospital process composite performance. The box plot displays the median, interquartile range, maximum, minimum with a given group. *P value < 0.05. (A) Overall study population; (B) Hospital type: private hospitals (B1) and public hospitals (B2); (C) Hospital level: tertiary hospitals (C1), secondary hospitals (C2); (D) Hospital affiliation: University-Affiliated hospitals (D1), nonaffiliated hospitals (D2); (E) Geographic region: east (E1), midland (E2), and west (E3) of China; (F) health technician-to-bed ratio: F1, <1.03; F2, 1.03–1.50; F3, 1.50–2.0; F4, ≥2.0; G, nurse-to-bed ratio: G1, <0.4; G2, 0.4–0.6; G3, 0.6–0.8; G4, ≥0.8. N indicates number of hospitals. Adherence to individual quality indicators QI: quality indicator; IQR: interquartile range; CT: computed tomography; MRI: magnetic resonance imaging; ECG: electrocardiograph; HPCP: hospital process composite performance. All QIs were assessed among patients with definite indications but no documented contraindications. Observations that lacked of information about the care eligible definition were not included in the eligible population. Eligible for patients who were not ambulating by hospital day 2. Eligible for patients with low-density lipoprotein >2.6 mol/L, and accompanied by hypertension and diabetes. The sum of eligible patients of all indicators.
Achievable benchmark setting and predicted quality achievement
Figure 3 described the risk-adjusted process–outcome association. After adjusting for patient-level and hospital-level characteristics, adherence to QIs showed a positive association with independence rate. Every 10% increase in HPCP score was associated with a 49.9% higher proportion of independent patients (OR = 1.499, 95% CI: 1.440–1.560).
Association between hospital process performance and independence (modified Rankin Scale score ≤2) at discharge. Odds ratios (ORs) were showed per 10% increment in hospital process performance. All indicators uniformly adjusted for year and age at diagnosis, stroke subtype and severity, primary payer status, pattern of admission, comorbidities, geographic region, hospital type, hospital level, university-affiliated status, nurse-to-bed ratio, health technician-to-bed ratio, and annual outpatient volume.
Data-driven achievable benchmarks for individual QIs and their predicted quality achievement
IQR: interquartile range; CT: computed tomography; MRI: magnetic resonance imaging; ECG: electrocardiograph; HPCP: hospital process composite performance; IAR: improvement in overall adherence rate; IIR: predicted improvement in independence rate with benchmarking.
Benchmark subset was created by ranking hospitals in descending order by adherence of individual quality indicators and by sequentially pooling eligible patients until the combined size for sequential hospitals approached 10% across all eligible hospitals.
A total of 533,117 patients were included in the sensitivity analysis. The predicted quality achievement with benchmarking for QIs slightly changed, but the QIs with high increase in both overall adherence rate and independence rate did not change (see online supplementary table V).
Discussion
Quality-of-care evaluation comparisons between health care providers might reveal current medical service needs and identify performance gaps in the implementation of guidelines. Setting attainable performance targets can facilitate quality improvement by increasing adherence to evidence-based guidelines. Using a nationwide clinical database of patients with AIS, we have demonstrated the positive associations between adherence rates of QIs and independence (mRS score ≤ 2) rates. We provided achievable performance benchmarks for the nine QIs and HPCP, and we speculated the net gain in quality IIR at discharge if all hospitals were to operate at the benchmark level. The QIs with high increase in both overall adherence rate and independence rate were three acute treatments of AIS, including thrombolytic therapy, anticoagulant therapy, venous thrombosis prophylaxis. The results suggested that quality improvement of stroke care should prioritize the three QIs of acute treatments.
Our study found that the proportion of coexisting diseases was higher in the independent group than in the dependent/dead group and the number of coexisting conditions affected the adherence to QIs, possibly because of differences in patients’ motivation to adhere and perceived care benefit. Better adherence to prescribed therapy is associated with better clinical outcomes. Treatment effectiveness is largely dependent on a patient’s willingness and ability to follow the medical recommendations. Patients with comorbid conditions may be more knowledgeable with the importance of receiving appropriate treatment, but the ability to follow the prescribed therapy decreased as the number of coexisting diseases increased.
Achievable performance benchmarks were based on data derived from assessing actual performance in a predefined, objective, and standardized manner. These benchmarks represented an attainable level of excellence that has already been achieved by a few superior providers, so that their practices might be widely understood and emulated. 20 Focusing on the top decile of the eligible population ensured that high-performing providers with low case volumes did not unduly influence the benchmark levels.8,21 Our study extended previous work in this field by predicting the possible quality improvement of performance benchmarks setting.22,23 Any quality improvement project or technique must anticipate the extent of quality improvement, in terms of both process of care and patient-relevant outcomes, in a relatively reasonable and cost-effective manner. It is usually impractical and time-consuming to conduct randomized trials to determine the effects of care performance-improvement projects on outcomes. 24 Instead, relying on the process–outcome association and using self-control method, we predicted the proportion of independent patients at discharge if all hospitals were to operate at the benchmark level, as they would in more strictly controlled randomized trials. 8 We observed an increase in the independence rate for all QIs. Although this was exclusively a data-based estimation, it does shed light on the desired effect of ensuring timely and high-quality care for stroke. Additionally, the calculation of predicted quality improvement before the benchmark intervention can provide evidences for the rational selection of QIs for performance improvement and provide additional motivation for promoting the implementation of and compliance with interventions.
It is essential to ensure that healthcare benchmarking achieves its objective. We think two elements should be considered when determining which QIs to prioritize in improving the quality of stroke care: there is enough room for the overall adherence rate to improve (bigger IAR) and it has great impact on outcomes (bigger IIR). Antiplatelet and statins therapy have high starting median adherence rate (98.75% and 92.07%); thus, the ceiling effect may have limited the degree to which any institution could improve their performance. The QIs with larger IAR and larger IIR values were thrombolytic therapy, anticoagulant therapy, venous thrombosis prophylaxis. These QIs are acute treatments of AIS, especially thrombolytic therapy. Research shows that increased quality of care during the early phase of stroke could significantly reduce the risk of disability and mortality. 25 Brain is exquisitely sensitive to ischemic injury and most irreversible injury occurs within 4–6 h after stroke onset. 26 Placebo-controlled trials have shown a substantial benefit of treatment with rt-PA in AIS patients within 3 h of stroke onset.27,28 Failure to seek medical attention promptly and the strict therapeutic window for rt-PA delivery are probably contributors to the low adherence rate. Anticoagulant therapy, venous thrombosis prophylaxis should be prescribed within 48 h of admission. In patients with reduced mobility, stroke is strongly associated with an increased risk of DVT. DVT may lead to pulmonary emboli, a frequent cause of avoidable deaths. 29 Large room for improvement in both adherence rate and independence rate suggested that many patients still do not receive optimal acute cares, and this in turn is responsible for many avoidable disabilities and deaths. Setting performance targets for the above three indicators could best motivate positive change in both overall adherence rate and independence rate at discharge.
There exist several limitations in this study. Firstly, the roles of indicators in the causal pathway between process care and outcomes can influence IIR. Indicators such as diagnosis and examination indicators don’t have a direct association with outcome. They are part of the causal pathway. This may be one of reasons why the IIR of these indicators were lower than those with level 1 evidences to improve patient outcomes. However, the causal pathway between process care and outcomes is highly complex and the inference of the causality is highly limited by the retrospective cross-sectional nature of our study. Secondly, the 10% target level was somewhat arbitrary. Achievable benchmark setting is flexible, and other users could, if they wished, select a different cutoff percentage, like 15%, 23 25%. 30 Thirdly, a more in-depth covariate analysis of patient and provider characteristics is needed to better understand the process–outcome association. Fourthly, because we did not have access to outpatient follow-up information, we were unable to obtain mRS at a fixed time poststroke, e.g., at 30 or 90 days. Lastly, this is a data-based estimate only, whether improvements in outcomes will follow improvements in performance remains to be seen.
Conclusion
We set achievable benchmarks for a broad spectrum of QIs based on long-term medical records on stroke care practices across China and determined the predicted quality improvement in independence (mRS score ≤ 2) rate at discharge if all hospitals were to operate at the benchmark level. Performance targets for three acute treatments, including thrombolytic therapy, anticoagulant therapy, venous thrombosis prophylaxis, could best motivate improvements in both overall adherence rate and independence rate at discharge. The finding suggests that the above three types of acute treatment should be given priority to improve the quality of AIS care.
Footnotes
Acknowledgements
The authors thank Chang Yin for providing data support in the study.
Declaration of conflicting interests
The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding
The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported by National Natural Science Foundation of China (81573255 to Meina Liu).
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