Background and Purpose
The quality of after-hour emergency care of patients with acute ischemic stroke is debatable. We therefore, sought to analyze the performance measures, quality of care and clinical outcomes in these patients admitted during off-hours.
Our study included 4493 patients from a selected cohort of patients admitted to the hospitals with ischemic stroke in the China National Stroke Registry (CNSR) from September 2007 to August 2008. On-hour presentation was defined as arrival at the emergency department from the scene between 8AM and 5PM from Monday through Friday. Off-hours included the remainder of the on-hours and statutory holidays. The association between off-hour presentation and outcome was analyzed using multivariate logistic-regression models.
Off-hour presentation was identified in 2672 (59.5%) patients with ischemic stroke. Comparison of patients admitted during off-hours with those admitted during on-hours revealed an unadjusted odds ratio of in-hospital mortality of 1.38 (95% confidence interval, 1.04–1.85), which declined to 1.34 (95% confidence interval, 0.93–1.93) after adjusting for patient characteristics (especially, pre-hospital delay). No difference in 30-day mortality, total death or dependence at three, six and 12 months between two groups was observed. No association between off-hour admission and quality of care was found.
In the CNSR database, compared with on-hour patients, off-hour patients with acute ischemic stroke admitted to the emergency departments from scene manifested a higher incidence of in-hospital mortality. However, the difference in incidence and quality of care between the groups disappeared after adjusting for pre-hospital delay and other variables.
Citation: Wang G, Liu G, Zhang R, Ji R, Gao B, Wang Y, et al. (2015) Evaluation of Off-Hour Emergency Care in Acute Ischemic Stroke: Results from the China National Stroke Registry. PLoS ONE 10(9): e0138046. https://doi.org/10.1371/journal.pone.0138046
Editor: Jinglu Ai, St Michael's Hospital, University of Toronto, CANADA
Received: March 30, 2015; Accepted: August 24, 2015; Published: September 17, 2015
Copyright: © 2015 Wang et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Data Availability: All relevant data are within the paper and its Supporting Information files.
Funding: This study was funded by the Ministry of Science and Technology and the Ministry of Health of the People’s Republic of China: National Science and Technology Major Project of China (2008ZX09312–008) and State Key Development Program of Basic Research of China (2009CB521905). The grant numbers are the National 11th & 12th Five-year S & T Major Project (2006BAI01A11, 2011BAI08B01, 2011BAI08B02) and Beijing Biobank of Cerebral Vascular Disease (D131100005313003). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Competing interests: The authors have declared that no competing interests exist.
Stroke is the second leading cause of death worldwide. From 1990 to 2010, the age-standardized incidence of stroke and burden of stroke increased in both developing and developed countries . Improving quality of care is critical to improve the prognosis after stroke. A higher incidence of mortality and a decreased use of invasive cardiac procedures was noticed in patients admitted with myocardial infarction during weekends, a phenomenon termed the “weekend effect” . Several studies of patients with stroke have reported higher mortality on weekends and weekday nights [3–8]. A recent systematic review and meta-analysis suggests that patients with acute ischemic stroke presenting during off-hours had higher short-term mortality and disability compared with patients presenting during regular hours. The result was robust across subgroups and sensitivity analyses . However, other studies found no significant association between time of admission and stroke care or poor outcomes [10–18]. Since these conflicting results may be based on differences in patient characteristics or differences in the quality of care provided by different medical service systems, prospective clinical registry databases with detailed patient data are needed to establish the role of these factors.
The purpose of this study was to examine whether off-hour presentation was associated with an impact on the quality of care (QOC), mortality or functional outcomes at discharge, one, three, six and 12 months after stroke onset in patients with acute ischemic stroke (AIS) admitted to hospital emergency departments (EDs) in the China National Stroke Registry (CNSR).
CNSR is a well-designed, nationwide, prospective cohort database of consecutive stroke patients (older than 18 years) admitted to 132 participating hospitals within 14 days of stroke onset between September 2007 and August 2008 . Acute stroke included ischemic stroke, intracerebral hemorrhage, and subarachnoid hemorrhage. The study was approved by the central Institutional Review Board at Beijing Tiantan Hospital. All patients or their designated proxies provided written informed consent. They consented to participate in this specific study, to have their data entered into the CNSR database and to have their medical data used in future research. These data were fully anonymized and de-identified prior to access.
AIS was diagnosed according to World Health Organization criteria  and confirmed using brain computed tomography or magnetic resonance imaging. We chose a cohort of patients admitted to the hospitals with AIS (excluding transient ischemic attack (TIA) and hemorrhagic stroke) that were admitted to the EDs from scene. We excluded subjects admitted to intensive care units (ICUs) and in-patient wards because the patients were those who had initially been admitted to an ICU or in-patient wards for other reasons prior to stroke and who usually had severe medical conditions. We excluded subjects admitted to hospitals from outpatient clinics as they had a milder stroke than other patients and seldom received recombinant tissue plasminogen activator (rTPA, also known as IV rtPA) since thrombolytic therapy were not used in outpatient clinics in Chinese acute care hospitals. We excluded subjects transferred to EDs from other hospitals with probably more severe conditions and poor outcomes.
We collected the clinical demographics of patients, including age, sex, body-mass index (BMI) at admission, education, vascular risk factors and concomitant diseases (prior stroke/ TIA, smoking, heavy drinking, hypertension, coronary heart disease, atrial fibrillation or flutter, peripheral vascular disease, diabetes mellitus, hyperlipidemia), management (time from onset to admission within three hours (pre-hospital dalay), IV rtPA within three hours of arrival, swallowing assessment, and length of hospitalization), pneumonia and urinary tract infection. The severity of neurologic impairment was evaluated using the National Institutes of Health Stroke Scale (NIHSS) score . The clinical subtypes of ischemic stroke were classified according to Oxfordshire Community Stroke Project (OCSP) criteria. Clinical status on admission was assessed using the modified Rankin Scale (mRS). The patients were admitted to intervention departments of hospital (including stroke unit, neurology ward, neurosurgical intervention, NICU/ICU). CNSR only included grade II hospitals (which serve several communities) and grade III hospitals (designated as teaching hospitals) .
Based on their arrival time at the EDs, we classified patients into on-hour versus off-hour presentation groups. On-hour presentation was defined as arrival at the emergency department between 8AM and 5PM Monday through Friday. Off-hour presentation was defined as arrival during the remainder of the on-hours and statutory holidays.
There are currently 13 performance measures for patients with ischemic stroke in China . Except for NIHSS scores at admission, length of stay, and hospital charges, the main performance measures of acute ischemic stroke in China were included in the ten parameters established in the United States. The ten performance indicators  quantifying the QOC provided to the AIS admissions are listed in S1 Table. We identified patients as eligible or ineligible for performance indicators according to neurologists treating the patient-diagnosed contraindications.
Follow-up and Outcomes
At one, three, six, and 12 months, the patient outcomes were evaluated via a telephone follow-up, including death (or mRS = 6) and dependency (defined as mRS = 3 to 5 considered as moderate-to-severe disability). Death was assessed as death due to any cause. Disability was measured by the mRS from 0 to 5. Poor outcomes were defined as death (mRS = 6) or dependency (mRS = 3 to 5). The telephone follow-up was based on a standardized interview protocol.
Clinical demographics, QOC and outcomes in patients with AIS at emergency admission were compared between on-hours versus off-hours, using χ2 tests for comparison of categorical variables, Student t tests for comparison of the means of continuous variables, and Wilcoxon 2-sample tests for comparison of the medians of continuous variables. The association between off-hour presentation and death and dependency was analyzed in multivariate logistic-regression models, after adjusting for age, sex, NIHSS, smoking, drinking, hypertension, coronary heart disease, atrial fibrillation, diabetes mellitus, dyslipidemia, arrival time within three hours of onset and IV rtPA. All tests were 2-tailed, and a probability value < 0.05 was considered significant in univariable and multivariable analyses. Data were analyzed with SAS software, version 9.1.3 (SAS Institute, Inc., Cary, North Carolina).
Of the 22,216 patients with stroke or TIA enrolled in the CNSR, 14,526 were diagnosed with AIS. At one year after stroke onset, follow-up information was available for 12,415 patients with AIS. We excluded subjects that were admitted to ICUs (n = 86), in-patient wards (n = 1566), out-patient clinics (n = 3177) and those transferred to EDs from other hospitals (n = 1682) and missing subjects (n = 199). The final sample included 5705 patients. Patients without an exact time of admission were excluded (n = 1212). Ultimately, 4493 were included in the present study (Fig 1).
Clinical characteristics of the analyzed population (n = 4493) were compared with patients without exact admission time and excluded from the analyzed patients (n = 1212). No differences in demographic characteristics or risk factor profiles were identified between the two groups, except for the NIHSS score and rtPA within three hours of stroke onset, as shown in S2 Table. Patients with exact admission time had higher NIHSS scores at admission and were more likely to receive rtPA compared with those without admission time.
A total of 2672(59.5%) AIS patients were admitted during off-hours. Table 1 shows the demographic profile of AIS patients admitted to the EDs between on-hours and off-hours. The off-hour admission group was slightly younger than the on-hour group (mean age, 66.8 versus 67.5 years, p = 0.056). There were no differences between the two groups in terms of sex, BMI, education, pre-mRS, prior stroke, vascular risk factors, OCSP subtypes, complications, length of hospitalization and intervention departments of hospital. NIHSS scores at admission were similar in the two groups (p = 0.504). Patients who were admitted within three hours of stroke onset constituted a higher proportion in the off-hour group (39.2% versus 33.5%, P < 0.001). No difference was found in the patients with IV rtPA within three hours of stroke onset during off-hours compared with on-hours (3.0% versus 2.8%, P = 0.760). Hospital levels were comparable in the two groups.
No significant difference was observed in the quality of care provided to patients admitted to hospital during off-hours and on-hours (Table 2). The proportion of patients who received stroke health education during off-hours was slightly higher than those during on-hours (67.4% vs 64.4% P = 0.070), similar to the proportion with smoking cessation (61.6% vs 57.6%) and rehabilitation assessment (50.6% vs 48.3%). However, DVT prophylaxis rates, rates of thrombolytic therapy and dysphagia screening rates were slightly lower during off-hour admissions (40.5% vs 41.9%, 14.1% versus 15.6%, 46.2% vs 48.6%). A slightly higher number of patients were discharged on anticoagulation for atrial fibrillation during off-hour admissions (23.1% vs 18.8%), similar to those discharged on cholesterol-reducing medication (38.1% vs 37.3%) and antithrombotic therapy (66.9% vs 64.8%).
Improved organization of stroke services may have a huge impact on stroke outcomes. We therefore, assessed the off-hour effect on quality of care indices between grade II and grade III hospitals (S3 Table) and found no difference between two groups.
Table 3 shows that the in-hospital mortality rate was 5.4% for off-hour presentation compared with 4.0% for on-hour presentation (P = 0.028). The multivariate logistic-regression analysis suggested that the in-hospital mortality during off-hour admissions decreased the odds ratio to 1.34 (95%CI, 0.93–1.93; P = 0.118) compared with on-hour admissions after adjusting for patient characteristics, in particular, pre-hospital delay (Table 4). There were no differences in 30-day mortality, total death or dependence at three, six and 12 months between two groups.
In this study, we investigated the association between off-hour presentation and outcomes in patients with acute ischemic stroke. We found that in-hospital mortality was slightly higher in patients with ischemic stroke admitted to hospital emergency departments during off-hours compared with on-hours (5.4% vs 4.0%, p = 0.028). After adjustment for potential confounding variables, no association between off-hour presentation and increased mortality was observed. Further, no significant differences were detected in the quality of stroke care provided during off-hour admissions compared with on-hours.
Previous studies reported a “weekend effect” in that stroke patients admitted on weekends or weekday nights had worse outcomes including increased seven-day mortality, in-hospital mortality, 30-day and 90-day mortality, 90-day mRS or decreased discharge to usual place of residence [3–8]. The effect was attributed to suboptimal quality of care (care effect) or more severe disease (patient effect). An Australian study of 539,122 patients admitted to emergency departments of all 501 hospitals in New South Wales between 2000 and 2007 suggested that higher in-hospital mortality of stroke on weekend admissions was due to reduced quality of care and different patient cohorts . Another study examined data from 82,219 ischemic stroke admissions to 115 Dutch hospitals between 2000 and 2004 and reported increased deaths from midnight to 7:00 and decreased death incidence from 14:00 to 18:00 compared with admissions at 8:00. The protective effect during shift changes suggested that increasing the number of staff available improved quality of care and outcome . A Swedish study found that the “weekend effect” decreased with time (with increased quality of stroke care) . In addition, the “weekend effect” was reduced or eliminated by participating in stroke clinical improvement programs such as Get With the Guidelines (GWTG)  or using comprehensive stroke centers . However, these studies were correlated with large administrative databases and retrospective studies, with limited clinical data for outcomes research, such as severity of stroke. Recent single- or multi-center prospective studies found no “weekend effect” when adjusted for NIHSS score, pre-hospital delay or other factors [15,16]. In our cohort of patients admitted to the emergency departments with AIS in the CNSR, no significant differences were found in demographics and severity of stoke (expressed by NIHSS score) except for pre-hospital delay.
A recent study of stroke care in the Denmark (using the Danish Stroke Registry) found that patients admitted during off-hours showed a lower degree of compliance with 8 out of 10 performance measures between 2003 and 2011 . In contrast, our study showed that patients admitted during off-hours did not receive a poorer quality of care between 2007 and 2008 in the CNSR database. Differences in study design may account for the differences in the Danish study and our study. The Danish study was limited to admissions with a first-ever acute stroke in university or non-university Danish hospitals, whereas our study was limited to patients admitted with ischemic stroke at the Grade II or III hospital (more likely to be tertiary care hospitals in urban areas) emergency departments. Further, we included holiday admissions in the off-hour cohort, unlike the Danish study, which reported that the admission time-related differences in care were substantially reduced over time (after implementation of a national systematic quality improvement program).
Interestingly, we found that the off-hour group may be more likely to receive stroke health education compared with on-hour group (67.4% vs 64.4%, P = 0.070) in our study. One possible explanation is that patients admitted to the hospital during off-hours were customarily considered to have more severe stroke by physicians . Therefore, doctors spend more time explaining the condition and provide more stroke prevention education. Patients were also more likely to be with family members during off-hours. Therefore, family members may pay more attention to the patient’s condition and be more likely to receive prevention information of stroke. In addition, thrombolysis between the two groups was similar. However, the rate of arrival time from stroke onset to admission within three hours in the off-hour presentation group was higher than in on-hour group (P < 0.001) suggested that the thrombolytic rate in off-hour presentation in China may be relatively lower compared with on-hour presentation. Approximately 2% of all patients with AIS from the CNSR  and in our study 2.5% of all patients with AIS admitted to the EDs from scene received thrombolysis with IV rtPA within three hours of admission, which was lower than the thrombolysis in United States and Germany [13, 29]. The finding suggests that efforts should be increased to improve the rate of thrombolysis by optimizing the process of thrombolysis during weekends or off-hours. Although we found no significant differences of quality of stroke care in the CNSR database between off-hour and on-hour admissions, it is possible that these performance measures do not reflect the overall quality of stroke care provided by acute hospitals due to lack of utilization of clinical interventions such as carotid endarterectomy, hypertension control, and use of stroke units. Thus, our findings do not negate the need for initiatives aimed at improving staffing and access to resources on off-hour presentations.
In addition, a recent systematic review and meta-analysis suggested that off-hour presentation of patients with acute ischemic stroke was associated with significantly higher short-term mortality (OR, 1.11, 95% CI 1.06–1.17) . Comparison of off-hours versus regular hours was categorized as: 1) weekend and night vs. weekday regular hours, 2) weekend vs. weekday, or 3) night vs. day. Because the study had a high heterogeneity (I2 > 80%), the subgroup analyses showed no higher short-term mortality between weekend and night vs. weekday regular hour (OR, 1.11, 95% CI 0.99–1.25), similar to our study. The finding suggests that the differences in mortality or disability between off- and on-hours are attributed to differences in population demographics and clinical characteristics or healthcare services in different countries.
Currently, the level of quality of stroke care in multicenter clinical registry or national database in China is unknown. However, a recent Chinese study found that stroke patients admitted to 109 grade III class A hospitals between 2007 and 2010 showed a declined in-hospital mortality (from 3.2% to 2.3%), indicating improvements in care and prevention of acute stroke . The in-hospital mortality in this study was nearly equal to the data from the China National Stroke Registry , but lower than that of Germany and the United States.
In the CNSR, most stroke patients were admitted into stroke units and neurology wards. The stroke units offer acute medical treatment and multidisciplinary care under a standardized protocol for diagnosis, treatment and rehabilitation of patients with acute stroke. The neurology wards serve patients with diseases of the nervous system and not stroke alone. In our study, we found no off-hour effect on admission ward. Additionally, no off-hour impact was seen on quality of stroke care between Grade II and Grade III. Our study suggests that patients in the CNSR database with acute ischemic stroke admitted to hospital EDs from scene received a consistent quality of care round the clock.
The strength of our study is related to the use of a prospective database that was adjusted for the clinical state at admission such as pre-hospital delay, and severity of stroke. Our database records the date and time of admission, and thus provides an opportunity to investigate the quality of care and poor outcome on weekends, weekday nights and statutory holidays when staffing and available resources are relatively reduced.
There are several limitations in our study. First, the admission of 1212 (21.2%) patients first admitted to the EDs was not accurately recorded, leading to possible bias. However, baseline characteristics of the groups with known and unknown admission time were comparable except for NIHSS score at admission, which was higher in the former group. The use of rt-PA within three hours after onset showed a similar trend. Second, the hospitals that participated in the CNSR were voluntary and focused on research, and were more likely to be tertiary care hospitals in urban areas and therefore endowed with greater resources and stroke specialties than smaller hospitals in rural areas. Thus, the general conclusions of this study may not apply to other types of institutions or countries with different health care systems.
In the CNSR database from 2007 to 2008, no associations were seen between hospital admission time and mortality in patients with acute ischemic stroke first admitted to the EDs even after adjustment for pre-hospital delay and other parameters. No significant difference was found in quality-of-care indicators in off-hour presentations compared with on-hour cases.
S1 Table. Current Stroke Performance Measures as Endorsed by the Major Stroke Quality Improvement Organizations in the United States.
Abbreviations: DVT, deep vein thrombosis; AF, atrial fibrillation; EMS, emergency medical services.
S2 Table. Patient Profile with or without Admission Time after Ischemic Stroke.
Abbreviations: AT, admission time; SD, standard deviation; IQR, interquartile range; NIHSS, National Institutes of Health Stroke Scale; IV rtPA, intravenous recombinant tissue-type plasminogen activator.
We thank all participating hospitals, colleagues, nurses, imaging and laboratory technicians for the CNSR.
Conceived and designed the experiments: Yongjun Wang. Performed the experiments: Yilong Wang GW BG ZL. Analyzed the data: GW GL RZ RJ ZL. Contributed reagents/materials/analysis tools: GW GL RZ. Wrote the paper: GW BG. Statistical analysis: GL RZ YP.
- 1. Feigin VL, Forouzanfar MH, Krishnamurthi R, Mensah GA, Connor M, Bennett DA, et al. Global and regional burden of stroke during 1990–2010: findings from the Global Burden of Disease Study 2010. Lancet. 2014; 383: 245–254. pmid:24449944
- 2. Kostis WJ, Demissie K, Marcella SW, Shao YH, Wilson AC, Moreyra AE, et al. Weekend versus weekday admission and mortality from myocardial infarction. N Engl J Med. 2007; 356: 1099–1109. pmid:17360988
- 3. Janszky I, Ahnve S, Ljung R. Weekend versus weekday admission and stroke outcome in Sweden from 1968 to 2005. Stroke. 2007; 38: e94; author reply e95. pmid:17656663
- 4. Saposnik G, Baibergenova A, Bayer N, Hachinski V. Weekends: a dangerous time for having a stroke? Stroke. 2007; 38: 1211–1215. pmid:17347472
- 5. Reeves MJ, Smith E, Fonarow G, Hernandez A, Pan W, Schwamm LH, et al. Off-hour admission and in-hospital stroke case fatality in the get with the guidelines-stroke program. Stroke. 2009; 40: 569–576. pmid:18988914
- 6. Fang J, Saposnik G, Silver FL, Kapral MK, Investigators of the Registry of the Canadian Stroke N. Association between weekend hospital presentation and stroke fatality. Neurology. 2010; 75: 1589–1596. pmid:21041782
- 7. Ogbu UC, Westert GP, Slobbe LC, Stronks K, Arah OA. A multifaceted look at time of admission and its impact on case-fatality among a cohort of ischaemic stroke patients. J Neurol Neurosurg Psychiatry. 2011; 82: 8–13. pmid:20667853
- 8. Palmer WL, Bottle A, Davie C, Vincent CA, Aylin P. Dying for the weekend: a retrospective cohort study on the association between day of hospital presentation and the quality and safety of stroke care. Arch Neurol. 2012; 69: 1296–1302. pmid:22777008
- 9. Sorita A, Ahmed A, Starr SR, Thompson KM, Reed DA, Dabrh AM, et al. Off-hour presentation and outcomes in patients with acute ischemic stroke: a systematic review and meta-analysis. Eur J Intern Med. 2014; 25: 394–400. pmid:24721584
- 10. Jauss M, Oertel W, Allendoerfer J, Misselwitz B, Hamer H. Bias in request for medical care and impact on outcome during office and non-office hours in stroke patients. Eur J Neurol. 2009; 16: 1165–1167. pmid:19469835
- 11. Albright KC, Raman R, Ernstrom K, Hallevi H, Martin-Schild S, Meyer DM, et al. Can comprehensive stroke centers erase the 'weekend effect'? Cerebrovasc Dis. 2009; 27: 107–113. pmid:19039213
- 12. Hoh BL, Chi YY, Waters MF, Mocco J, Barker FG 2nd. Effect of weekend compared with weekday stroke admission on thrombolytic use, in-hospital mortality, discharge disposition, hospital charges, and length of stay in the Nationwide Inpatient Sample Database, 2002 to 2007. Stroke. 2010; 41: 2323–2328. pmid:20724715
- 13. Kazley AS, Hillman DG, Johnston KC, Simpson KN. Hospital care for patients experiencing weekend vs weekday stroke: a comparison of quality and aggressiveness of care. Arch Neurol. 2010; 67: 39–44. pmid:20065127
- 14. McKinney JS, Deng Y, Kasner SE, Kostis JB, Myocardial Infarction Data Acquisition System Study G. Comprehensive stroke centers overcome the weekend versus weekday gap in stroke treatment and mortality. Stroke. 2011; 42: 2403–2409. pmid:21868723
- 15. Martinez-Martinez MM, Fernandez-Travieso J, Fuentes B, Ruiz-Ares G, Martinez-Sanchez P, Cazorla Garcia R, et al. Off-hour effects on stroke care and outcome in stroke centres. Eur J Neurol. 2012; 19:1140–1145. pmid:22435893
- 16. Streifler JY, Benderly M, Molshatzki N, Bornstein N, Tanne D. Off-hours admission for acute stroke is not associated with worse outcome—a nationwide Israeli stroke project. Eur J Neurol. 2012; 19: 643–647. pmid:22136626
- 17. Bejot Y, Aboa-Eboule C, Jacquin A, Troisgros O, Hervieu M, Durier J, et al. Stroke care organization overcomes the deleterious 'weekend effect' on 1-month stroke mortality: a population-based study. Eur J Neurol. 2013; 20: 1177–1183. pmid:23551852
- 18. Kim C, Jang MU, Oh MS, Park JH, Jung S, Lee JH, et al. Off-hour effect on 3-month functionaloutcome after acute ischemic stroke: a prospective multicenter registry. PLoS One. 2014; 9: e105799. pmid:25165816
- 19. Wang Y, Cui L, Ji X, Dong Q, Zeng J, wang Y, et al. The China National Stroke Registry for patients with acute cerebrovascular events: design, rationale, and baseline patient characteristics. Int J Stroke. 2011; 6: 355–361. pmid:21609414
- 20. Stroke—1989. Recommendations on stroke prevention, diagnosis, and therapy. Report of the WHO Task Force on Stroke and other Cerebrovascular Disorders. Stroke. 1989; 20: 1407–1431. pmid:2799873
- 21. Brott T, Adams HP Jr, Olinger CP, Marler JR, Barsan WG, Biller J, et al. Measurements of acute cerebral infarction: a clinical examination scale. Stroke. 1989; 20: 864–870. pmid:2749846
- 22. Minister of Health. Acts for Hospital Classification. china: Minister of health,1989.
- 23. Minister of Health. Single disease quality management manual of chinese hospotal Association of the medical department guidance. science and technology literature press, version 2.0; 2010.pp. 142–197.
- 24. Reeves MJ, Parker C, Fonarow GC, Smith EE, Schwamm LH. Development of stroke performance measures: definitions, methods, and current measures. Stroke. 2010; 41: 1573–1578. pmid:20489174
- 25. Concha OP, Gallego B, Hillman K, Delaney GP, Coiera E. Do variations in hospital mortality patterns after weekend admission reflect reduced quality of care or different patient cohorts? A population-based study. BMJ Qual Saf. 2014; 23: 215–222. pmid:24163392
- 26. Kristiansen NS, Mainz J, Norgard BM, Bartels PD, Andersen G, Johnsen SP. Off-hours admission and acute stroke care quality: a nationwide study of performance measures and case-fatality. Stroke. 2014; 45: 3663–3669. pmid:25378421
- 27. Manfredini R, Boari B, Salmi R. Higher stroke mortality on weekends: are all strokes the same? troke. 2007; 38: e112; author reply e114.
- 28. Wang Y, Liao X, Zhao X, Wang DZ, Wang C, Nguyen-Huynh MN, et al. Using recombinant tissue plasminogen activator to treat acute ischemic stroke in China: analysis of the results from the Chinese National Stroke Registry (CNSR). Stroke. 2011; 42: 1658–1664. pmid:21512182
- 29. Cloud G, Hoffman A, Rudd A, Intercollegiate Stroke Working P. National sentinel stroke audit 1998–2011. Clin Med. 2013; 13: 444–448. pmid:24115698
- 30. He Q, Wu C, Luo H, Wang ZY, Ma XQ, Zhao YF, et al. Trends in in-hospital mortality among patients with stroke in China. PLoS One. 2014; 9: e92763. pmid:24651454
- 31. Wang PL, Zhao XQ, Yang ZH, Wang AX, Wang CX, Liu LP, et al. Effect of in-hospital medical complications on case fatality post-acute ischemic stroke: data from the China National Stroke Registry.Chin Med J (Engl). 2012; 125: 2449–2454.