Case-mix Adjustment Research Articles

Effect of day of the week on short- and long-term mortality after emergency general surgery.

The effect of day of the week on outcome after surgery is the subject of debate. The aim was to determine whether day of the week of emergency general surgery alters short- and long-term mortality. This was an observational study of all patients undergoing emergency general surgery in Scotland between 1 January 2005 and 31 December 2007, followed to 2012. Multilevel logistic and Cox proportional hazards regression were used to assess the effect of day of the week of surgery on outcome after adjustment for case mix and risk factors. The primary outcome was perioperative mortality; the secondary outcome was overall survival. A total of 50 844 patients were identified, of whom 31 499 had an emergency procedure on Monday to Thursday and 19 345 on Friday to Sunday. Patients undergoing surgery at the weekend were younger (mean 45·9 versus 47·5 years; P < 0·001) and had fewer co-morbidities, but underwent riskier and/or more complex procedures (P < 0·001). Patients who had surgery at the weekend were more likely to have been operated on sooner than those who had weekday surgery (mean time from admission to operation 1·2 versus 1·6 days; P < 0·001). No difference in perioperative mortality (odds ratio 1·00, 95 per cent c.i. 0·89 to 1·13; P = 0·989) or overall survival (hazard ratio 1·01, 0·97 to 1·06; P = 0·583) was observed when surgery was performed at the weekend. There was no difference in overall survival after surgery undertaken on any particular day compared with Wednesday; a borderline reduction in perioperative mortality was seen on Tuesday. There was no difference in short- or long-term mortality following emergency general surgery at the weekend, compared with mid-week.

Patient satisfaction in musculoskeletal medicine.

This is a literature review of the measurement of patient satisfaction in musculoskeletal medicine. Its purpose is to better understand the motivation for such measurements, the potential confounders, and the potential physician behaviors that may modulate such measures. There have been studies documenting that physician conveyance of empathy, the extent to which patients' expectations for pain control and timeliness of care are met, as well as patient demographics and health status all affect the current measures of patient satisfaction. In the mission to affect patient-centered care are met, musculoskeletal providers will be measured by their patients' satisfaction. There is much yet to be understood regarding patients' expectations of care; the science behind case-mix adjustment in this sphere is in its infancy, but there are some compelling reasons for musculoskeletal providers to attempt to optimize their patients' satisfaction.

Exploring regional variability in utilization of antireflux surgery in children

BackgroundThere is significant variation surrounding the indications, surgical approaches, and outcomes for children undergoing antireflux procedures (ARPs) resulting in geographic variation of care. Our purpose was to quantify this geographic variation in the utilization of ARPs in children. MethodsA cross-sectional analysis of the 2009 Kid's Inpatient Database was performed to identify patients with gastroesophageal reflux disease or associated diagnoses. Regional surgical utilization rates were determined, and a mixed effects model was used to identify factors associated with the use of ARPs. ResultsOf the 148,959 patients with a diagnosis of interest, 4848 (3.3%) underwent an ARP with 2376 (49%) undergoing a laparoscopic procedure. The Northeast (2.0%) and Midwest (2.2%) had the lowest overall utilization of surgery, compared with the South (3.3%) and West (3.4%). After adjustment for age, case-mix, and surgical approach, variation persisted with the West and the South demonstrating almost two times the odds of undergoing an ARP compared with the Northeast. Surgical utilization rates are independent of state-level volume with some of the highest case volume states having surgical utilization rates below the national rate. In the West, the use of laparoscopy correlated with overall utilization of surgery, whereas surgical approach was not correlated with ARP use in the South. ConclusionsSignificant regional variation in ARP utilization exists that cannot be explained entirely by differences in patient age, race/ethnicity, case-mix, and surgical approach. In order to decrease variation in care, further research is warranted to establish consensus guidelines regarding indications for the use ARPs for children.

Access to principal treatment centres and survival rates for children and young people with cancer in Yorkshire, UK

BackgroundPrincipal Treatment Centres (PTC) were established to provide age-appropriate care as well as clinical expertise for children and young people with cancer. However, little is known about the effects of specialist treatment centres on survival outcomes especially for teenagers and young adults. This population-based study aimed to describe access to PTC and the associated trends in survival for 0–24 year olds accounting for stage of disease at presentation and treatment.MethodsPatients diagnosed from 1998–2009 aged 0–24 years were extracted from the Yorkshire Specialist Register of Cancer in Children and Young People, including information on all treating hospitals, followed-up until 31st December 2014. The six commonest cancer types were included: leukaemia (n = 684), lymphoma (n = 558), CNS tumours (n = 547), germ cell tumours (n = 364), soft tissue sarcomas (n = 171) and bone tumours (n = 163). Treatment was categorised into three groups: ‘all’, ‘some’ or ‘no’ treatment received at a PTC. Treatment at PTC was examined by diagnostic group and patient characteristics. Overall survival was modelled using Cox regression adjusting for case-mix including stage, treatment and other socio-demographic and clinical characteristics.ResultsOverall 72% of patients received all their treatment at PTC whilst 13% had no treatment at PTC. This differed by diagnostic group and age at diagnosis. Leukaemia patients who received no treatment at PTC had an increased risk of death which was partially explained by differences in patient case-mix (adjusted Hazard Ratio (HR) = 1.73 (95%CI 0.98–3.04)). Soft tissue sarcoma patients who had some or no treatment at PTC had better survival outcomes, which remained after adjustment for patient case-mix (adjusted HR = 0.48 (95%CI 0.23–0.99)). There were no significant differences in outcomes for other diagnostic groups (lymphoma, CNS tumours, bone tumours and germ cell tumours). For leukaemia patients survival outcomes for low risk patients receiving no treatment at PTC were similar to high risk patients who received all treatment at PTC, implying a benefit for care at the PTC.ConclusionThis study demonstrates that for leukaemia patients receiving treatment at a PTC is associated with improved survival that may compensate for a poorer prognosis presentation. However, further information on risk factors is needed for all diagnostic groups in order to fully account for differences in patient case-mix.

National Diabetes Audit 2015–2016 shows variations in care processes and targets

National Diabetes Audit 2015–2016 shows variations in care processes and targets

Adjusted Hospital Outcomes of Abdominal Aortic Aneurysm Surgery Reported in the Dutch Surgical Aneurysm Audit

The Dutch Surgical Aneurysm Audit (DSAA) is mandatory for all patients with primary abdominal aortic aneurysms (AAAs) in the Netherlands. The aims are to present the observed outcomes of AAA surgery against the predicted outcomes by means of V-POSSUM (Vascular-Physiological and Operative Severity Score for the enUmeration of Mortality and Morbidity). Adjusted mortality was calculated by the original and re-estimated V(physiology)-POSSUM for hospital comparisons. All patients operated on from January 2013 to December 2014 were included for analysis. Calibration and discrimination of V-POSSUM and V(p)-POSSUM was analysed. Mortality was benchmarked by means of the original V(p)-POSSUM formula and risk-adjusted by the re-estimated V(p)-POSSUM on the DSAA. In total, 5898 patients were included for analysis: 4579 with elective AAA (EAAA) and 1319 with acute abdominal aortic aneurysm (AAAA), acute symptomatic (SAAA; n=371) or ruptured (RAAA; n=948). The percentage of endovascular aneurysm repair (EVAR) varied between hospitals but showed no relation to hospital volume (EAAA: p=.12; AAAA: p=.07). EAAA, SAAA, and RAAA mortality was, respectively, 1.9%, 7.5%, and 28.7%. Elective mortality was 0.9% after EVAR and 5.0% after open surgical repair versus 15.6% and 27.4%, respectively, after AAAA. V-POSSUM overestimated mortality in most EAAA risk groups (p<.01). The discriminative ability of V-POSSUM in EAAA was moderate (C-statistic: .719) and poor for V(p)-POSSUM (C-statistic: .665). V-POSSUM in AAAA repair overestimated in high risk groups, and underestimated in low risk groups (p<.01). The discriminative ability in AAAA of V-POSSUM was moderate (.713) and of V(p)-POSSUM poor (.688). Risk adjustment by the re-estimated V(p)-POSSUM did not have any effect on hospital variation in EAAA but did in AAAA. Mortality in the DSAA was in line with the literature but is not discriminative for hospital comparisons in EAAA. Adjusting for V(p)-POSSUM, revealed no association between hospital volume and treatment or outcome. Risk adjustment for case mix by V(p)-POSSUM in patients with AAAA has been shown to be important.

Oncologist and organizational factors associated with variation in breast cancer multigene testing.

Multigene testing for breast cancer recurrence risk became available in 2007, yet many eligible patients remain untested. This study evaluated variation in testing rates, and oncologist and organizational factors associated with variation, in a setting without financial influences on testing. We conducted a retrospective cohort study using electronic data and oncologist surveys within Kaiser Permanente Northern California, a large integrated health care system. Analyses included all 2974 test eligible patients from 2013 to 2015, 113 oncologists, and 15 practice groups. Receipt of multigene testing was evaluated with generalized linear mixed models. Overall, 39% of eligible patients had multigene testing, but rates varied widely among practice groups, ranging from 24 to 48% after case mix adjustment. This 24% difference among practices was greater than the variation associated with most patient characteristics, including comorbidities and race/ethnicity, and similar to that associated with tumor size. Practice group and oncologist factors were statistically significant contributors to the variation in testing after adjusting for patient factors. Patients were more likely to be tested if they had a female oncologist (aOR 1.60, 95% CI 1.21-2.12) or were in a practice whose chief had a high testing rate (aOR 1.20, 95% CI 1.12-1.29 per 10% increase in the percent tested). Oncologist and leadership practices play a key role in the variation in genomic test use for cancer recurrence risk even in a healthcare system without financial barriers to testing and could be a leverage point for implementing desired practice changes for new genomic advances.

Association between day and time of admission to critical care and acute hospital outcome for unplanned admissions to adult general critical care units: cohort study exploring the ‘weekend effect’

BackgroundWe aimed to identify any association between day and time of admission to critical care and acute hospital outcome. MethodsWe conducted a cohort study using prospectively collected data from the national clinical audit of adult critical care. We included 195 428 unplanned admissions from 212 adult general critical care units in England, Wales and Northern Ireland, between April 1, 2013 and March 31, 2015 in the analysis. ResultsHourly admission rates for unplanned admissions varied more than three-fold during the 24 h cycle. Overall acute hospital mortality was 26.8%. Before adjustment, acute hospital mortality was similar between weekends and weekdays but was significantly lower for admissions at night compared with the daytime (−3.4%, −3.8 to −3.0%; P<0.001). After adjustment for casemix, there remained no difference between weekends and weekdays (−0.0%, −0.4 to +0.3%; P=0.87) or between nighttime and daytime (−0.2%, −0.5 to +0.1%; P=0.21). Delays in admission were reported for 4.3% of admissions and were slightly more common during weekdays than weekends and in the daytime than at night. Delayed admission was associated with a small increase in acute hospital mortality, but adjusting for this did not affect the estimates of the effect of day and time of admission. ConclusionsThe day of week and time of admission have no influence on patient mortality for unplanned admissions to adult general critical care units within the UK. Ways to improve critical care and hospital systems to minimize delays in admission and potentially improve outcomes need to be ascertained in future research.

Comparison of Patient Experience between a Practice for Homeless Patients and Other Practices Engaged in a Patient-Centered Medical Home Initiative.

Despite its increasing popularity, little is known about the patient-centered medical home (PCMH) model in primary care settings serving homeless populations. Our objective was to understand how patient experience differs between a PCMH demonstration practice designed for homeless people in Massachusetts and other practices participating in the same statewide initiative. The study population included 194 homeless patients and 1,868 patients from comparison practices. Patient experience was compared on key measures of patient-centeredness, while applying case-mix adjustment to control for sociodemographic and clinical factors. The practice for homeless patients scored higher than the comparison group on self-management support and behavioral health integration, while being equivalent on three other measures. Potential areas for improvement include measures related to communication, front desk staff, and timely appointments. We discuss possible explanations for the observed pattern of results in the context of the unique challenges faced by a practice designed to serve individuals experiencing homelessness.

The Society of Thoracic Surgeons Congenital Heart Surgery Database Public Reporting Initiative.

Three basic principles provide the rationale for the Society of Thoracic Surgeons (STS) Congenital Heart Surgery Database (CHSD) public reporting initiative: (1) Variation in congenital and pediatric cardiac surgical outcomes exist. (2) Patients and their families have the right to know the outcomes of the treatments that they will receive. (3). It is our professional responsibility to share this information with them in a format they can understand. The STS CHSD public reporting initiative facilitates the voluntary transparent public reporting of congenital and pediatric cardiac surgical outcomes using the STS CHSD Mortality Risk Model. The STS CHSD Mortality Risk Model is used to calculate risk-adjusted operative mortality and adjusts for the following variables: age, primary procedure, weight (neonates and infants), prior cardiothoracic operations, non-cardiac congenital anatomic abnormalities, chromosomal abnormalities or syndromes, prematurity (neonates and infants), and preoperative factors (including preoperative/preprocedural mechanical circulatory support [intraaortic balloon pump, ventricular assist device, extracorporeal membrane oxygenation, or cardiopulmonary support], shock [persistent at time of surgery], mechanical ventilation to treat cardiorespiratory failure, renal failure requiring dialysis and/or renal dysfunction, preoperative neurological deficit, and other preoperative factors). Operative mortality is defined in all STS databases as (1) all deaths, regardless of cause, occurring during the hospitalization in which the operation was performed, even if after 30 days (including patients transferred to other acute care facilities); and (2) all deaths, regardless of cause, occurring after discharge from the hospital, but before the end of the 30th postoperative day. The STS CHSD Mortality Risk Model has good model fit and discrimination with an overall C statistics of 0.875 and 0.858 in the development sample and the validation sample, respectively. These C statistics are the highest C statistics ever seen in a pediatric cardiac surgical risk model. Therefore, the STS CHSD Mortality Risk Model provides excellent adjustment for case mix and should mitigate against risk aversive behavior. The STS CHSD Mortality Risk Model is the best available model to date for measuring outcomes after pediatric cardiac surgery. As of March 2016, 60% of participants in STS CHSD have agreed to publicly report their outcomes through the STS Public Reporting Online website (http://www.sts.org/quality-research-patient-safety/sts-public-reporting-online). Although several opportunities exist to improve our risk models, the current STS CHSD public reporting initiative provides the tools to report publicly, and with meaning and accuracy, the outcomes of congenital and pediatric cardiac surgery.

Validation of the Pediatric Index of Mortality 3 in a Single Pediatric Intensive Care Unit in Korea.

To compare mortality rate, the adjustment of case-mix variables is needed. The Pediatric Index of Mortality (PIM) 3 score is a widely used case-mix adjustment system of a pediatric intensive care unit (ICU), but there has been no validation study of it in Korea. We aim to validate the PIM3 in a Korean pediatric ICU, and extend the validation of the score from those aged 0–16 to 0–18 years, as patients aged 16–18 years are admitted to pediatric ICU in Korea. A retrospective cohort study of 1,710 patients was conducted in a tertiary pediatric ICU. To validate the score, the discriminatory power was assessed by calculating the area under the receiver-operating characteristic (ROC) curve, and calibration was evaluated by the Hosmer-Lemeshow goodness-of-fit (GOF) test. The observed mortality rate was 8.47%, and the predicted mortality rate was 6.57%. For patients aged < 18 years, the discrimination was acceptable (c-index = 0.76) and the calibration was good, with a χ2 of 9.4 in the GOF test (P = 0.313). The observed mortality rate in the hemato-oncological subgroup was high (18.73%), as compared to the predicted mortality rate (7.13%), and the discrimination was unacceptable (c-index = 0.66). In conclusion, the PIM3 performed well in a Korean pediatric ICU. However, the application of the PIM3 to a hemato-oncological subgroup needs to be cautioned. Further studies on the performance of PIM3 in pediatric patients in adult ICUs and pediatric ICUs of primary and secondary hospitals are needed.

Mental Health Conditions and Medical and Surgical Hospital Utilization.

Mental health conditions are prevalent among children hospitalized for medical conditions and surgical procedures, but little is known about their influence on hospital resource use. The objectives of this study were to examine how hospitalization characteristics vary by presence of a comorbid mental health condition and estimate the association of a comorbid mental health condition with hospital length of stay (LOS) and costs. Using the 2012 Kids' Inpatient Database, we conducted a retrospective, nationally representative, cross-sectional study of 670 161 hospitalizations for 10 common medical and 10 common surgical conditions among 3- to 20-year-old patients. Associations between mental health conditions and hospital LOS were examined using adjusted generalized linear models. Costs of additional hospital days associated with mental health conditions were estimated using hospital cost-to-charge ratios. A comorbid mental health condition was present in 13.2% of hospitalizations. A comorbid mental health condition was associated with a LOS increase of 8.8% (from 2.5 to 2.7 days, P < .001) for medical hospitalizations and a 16.9% increase (from 3.6 to 4.2 days, P < .001) for surgical hospitalizations. For hospitalizations in this sample, comorbid mental health conditions were associated with an additional 31 729 (95% confidence interval: 29 085 to 33 492) hospital days and $90 million (95% confidence interval: $81 to $101 million) in hospital costs. Medical and surgical hospitalizations with comorbid mental health conditions were associated with longer hospital stay and higher hospital costs. Knowledge about the influence of mental health conditions on pediatric hospital utilization can inform clinical innovation and case-mix adjustment.

External Validation of a Case-Mix Adjustment Model for the Standardized Reporting of 30-Day Stroke Mortality Rates in China.

Background and PurposeA case-mix adjustment model has been developed and externally validated, demonstrating promise. However, the model has not been thoroughly tested among populations in China. In our study, we evaluated the performance of the model in Chinese patients with acute stroke.MethodsThe case-mix adjustment model A includes items on age, presence of atrial fibrillation on admission, National Institutes of Health Stroke Severity Scale (NIHSS) score on admission, and stroke type. Model B is similar to Model A but includes only the consciousness component of the NIHSS score. Both model A and B were evaluated to predict 30-day mortality rates in 13,948 patients with acute stroke from the China National Stroke Registry. The discrimination of the models was quantified by c-statistic. Calibration was assessed using Pearson’s correlation coefficient.ResultsThe c-statistic of model A in our external validation cohort was 0.80 (95% confidence interval, 0.79–0.82), and the c-statistic of model B was 0.82 (95% confidence interval, 0.81–0.84). Excellent calibration was reported in the two models with Pearson’s correlation coefficient (0.892 for model A, p<0.001; 0.927 for model B, p = 0.008).ConclusionsThe case-mix adjustment model could be used to effectively predict 30-day mortality rates in Chinese patients with acute stroke.

Large variation between hospitals in immediate breast reconstruction rates after mastectomy for breast cancer in the Netherlands

The present study aimed to describe the use of immediate breast reconstruction (IBR) after mastectomy for invasive breast cancer and ductal carcinoma in situ (DCIS) in hospitals in the Netherlands and determine whether patient and tumor factors account for the variation. Patients undergoing mastectomy for primary invasive breast cancer or DCIS diagnosed between January 1, 2011 and December 31, 2013 were selected from the NABON Breast Cancer Audit. All the 92 hospitals in the Netherlands were included. The use of IBR in all hospitals was compared using unadjusted and adjusted analyses. Patient and tumor factors were evaluated by univariate and multivariate analyses. In total, 16,953 patients underwent mastectomy: 15,072 for invasive breast cancer and 1881 for DCIS. Unadjusted analyses revealed considerable variation between hospitals in postmastectomy IBR rates for invasive breast cancer (mean 17%; range 0-64%) and DCIS (mean 42%; range 0-83%). For DCIS, younger age and multifocal disease were factors that significantly increased IBR rates. For patients diagnosed with invasive breast cancer, IBR was more often used in younger patients, multifocal tumors, smaller tumors, tumors with a lower grade, absence of lymph node involvement, ductal carcinomas, or hormone-receptor positive/HER2-positive tumors. After case-mix adjustments for these factors, the variation in the use of IBR between hospitals remained large (0-43% for invasive breast cancer and 0-74% for DCIS). A large variation between hospitals was found in postmastectomy IBR rates in the Netherlands for both invasive breast cancer and DCIS even after adjustment for patient and tumor factors.

Variation in Hospital Adoption Rates of Video-Assisted Thoracoscopic Lobectomy for Lung Cancer and the Effect on Outcomes

This study examined the variation in the adoption of video-assisted thoracoscopic surgery (VATS) for lobectomy across United States hospitals from a population-based national database. We used the National Cancer Data Base to identify patients undergoing lobectomy between 2010 and 2012 and used hierarchical regression to estimate case-mix-adjusted VATS lobectomy rates using patient and tumor characteristics. We stratified hospitals into quintiles by adjusted VATS lobectomy rates. To account for lack of equipment to perform minimally invasive thoracoscopic operations, we also obtained data on VATS wedge resections. Of 55,972 cancer lobectomies performed at 905 hospitals, 17,072 (30.5%) were VATS. Crude hospital VATS use varied widely (mean was 25.5% of all lobectomies per hospital; interquartile range, 4.4% to 42.3%). Variation persisted after case-mix adjustment. For example, VATS rates at the highest and lowest quintiles were 76% vs 0.6%, respectively. Differences in patient and tumor characteristics across quintiles were negligible, and there was no indication that those hospitals lacked VATS equipment. The risk-adjusted same-hospitalreadmission (6.7% vs 7%; p > 0.2), 30-day mortality (1.5% vs 1.5%; p>0.2), and 90-day mortality (2.9% vs 2.7%; p= 0.038) rates were similar between the highest and lowest quintiles. Length of stay was shorter at hospitals in the highest VATS quintile (6.6 vs 7.4 days; p < 0.001). Adoption of VATS lobectomy varies widely across United States hospitals. This variation cannot be explained by patient or tumor characteristics or by a shortage of VATS equipment. Efforts to reduce this variation will require the dissemination and implementation of novel training techniques and learning opportunities for surgeons.

A retrospective observational study of length of stay in hospital after colorectal cancer surgery in England (1998-2010).

The National Health Service (NHS) is facing financial constraints and thus there is considerable interest in ensuring the shortest but optimal hospital stays possible. The aim of this study was to investigate patterns of postoperative length of stay (LOS) stay across the English NHS and to identify factors that significantly influence both optimal and prolonged LOS.Data were obtained from the National Cancer Data Repository (NCDR). National patterns of LOS were examined and multilevel mixed effects logistic regression was used to study factors associated with an “ideal” (≤5 days) or a prolonged (≥21 days) LOS in hospital after major resection. Funnel plots were used to examine variation across hospitals in both risk-adjusted and unadjusted LOS.All 240,873 individuals who underwent major resection for colorectal cancer were diagnosed between 1998 and 2010 in the English NHS. The overall median LOS was 10 (interquartile range [IQR] 7–14 days) days, but it fell over time from 11 (IQR 9–15) days in 1998 to 7 (IQR 5–12) days in 2010. The proportion of people experiencing “ideal” LOS increased dramatically from 4.9% in 1998 to 34.2% in 2010, but the decrease in the proportion of patients who experienced a prolonged LOS was less marked falling from 11.2% to 8.4%, respectively. Control charts showed that there was significant variation in short and prolonged LOS across NHS trusts even after adjustment for case-mix.Significant variation in LOS existed between NHS hospitals in England throughout period 1998 to 2010. Understanding the underlying causes of this variation between surgical providers will make it possible to identify and spread best practice, improve services, and ultimately reduce LOS following colorectal cancer surgery.

High hospital research participation and improved colorectal cancer survival outcomes: a population-based study

ObjectiveIn 2001, the National Institute for Health Research Cancer Research Network (NCRN) was established, leading to a rapid increase in clinical research activity across the English NHS. Using colorectal cancer...

Validity of a stroke severity index for administrative claims data research: a retrospective cohort study

BackgroundAscertaining stroke severity in claims data-based studies is difficult because clinical information is unavailable. We assessed the predictive validity of a claims-based stroke severity index (SSI) and determined whether it improves case-mix adjustment.MethodsWe analyzed patients with acute ischemic stroke (AIS) from hospital-based stroke registries linked with a nationwide claims database. We estimated the SSI according to patient claims data. Actual stroke severity measured with the National Institutes of Health Stroke Scale (NIHSS) and functional outcomes measured with the modified Rankin Scale (mRS) were retrieved from stroke registries. Predictive validity was tested by correlating SSI with mRS. Logistic regression models were used to predict mortality.ResultsThe SSI correlated with mRS at 3 months (Spearman rho = 0.578; 95 % confidence interval [CI], 0.556–0.600), 6 months (rho = 0.551; 95 % CI, 0.528–0.574), and 1 year (rho = 0.532; 95 % CI 0.504–0.560). Mortality models with the SSI demonstrated superior discrimination to those without. The AUCs of models including the SSI and models with the NIHSS did not differ significantly.ConclusionsThe SSI correlated with functional outcomes after AIS and improved the case-mix adjustment of mortality models. It can act as a valid proxy for stroke severity in claims data-based studies.Electronic supplementary materialThe online version of this article (doi:10.1186/s12913-016-1769-8) contains supplementary material, which is available to authorized users.

The Auckland Cataract Study: Assessing Preoperative Risk Stratification Systems for Phacoemulsification Surgery in a Teaching Hospital

To evaluate 2 preoperative risk stratification systems for assessing the risk of complications in phacoemulsification cataract surgery, performed by residents, fellows, and attending physicians in a public teaching hospital. Cohort study. One observer assessed the clinical data of 500 consecutive cases, prior to phacoemulsification cataract surgery performed between April and June 2015 at Greenlane Clinical Centre, Auckland, New Zealand. Preoperatively 2 risk scores were calculated for each case using the Muhtaseb and Buckinghamshire risk stratification systems. Complications, intraoperative and postoperative, and visual outcomes were analyzed in relation to these risk scores. Intraoperative complication rates increased with higher risk scores using the Muhtaseb or Buckinghamshire stratification system (P= .001 and P=.003, respectively, n= 500). The odds ratios for residents and fellows were not significantly different from attending physicians after case-mix adjustment according to risk scores (P > .05). Postoperative complication rates increased with higher Buckinghamshire risk scores but not with Muhtaseb scores (P= .014 and P= .094, respectively, n= 476). Postoperative corrected-distance visual acuity was poorer with higher risk scores (P < .001 for both, n= 476). This study confirms that the risk of intraoperative complications increases with higher preoperative risk scores. Furthermore, higher risk scores correlate with poorer postoperative visual acuity and the Buckinghamshire risk score also correlates with postoperative complications. Therefore, preoperative assessment using such risk stratification systems could assist individual informed consent, preoperative surgical planning, safe allocation of cases to trainees, and more meaningful analyses of outcomes for individual surgeons and institutions.

Hospital Characteristics and the Agency for Healthcare Research and Quality Inpatient Quality Indicators: A Systematic Review

The Agency for Healthcare Research and Quality Inpatient Quality Indicators (IQIs) include inpatient mortality for selected procedures and medical conditions. They have assumed an increasingly prominent role in hospital comparisons. Healthcare delivery and policy-related decisions need to be driven by reliable research that shows associations between hospital characteristics and quality of inpatient care delivered. To systematically review the literature on associations between hospital characteristics and IQIs. We systematically searched PubMed and gray literature (2000-2012) for studies relevant to 14 hospital characteristics and 17 IQIs. We extracted data for study characteristics, IQIs analyzed, and hospital characteristics (e.g., teaching status, bed size, patient volume, rural vs. urban location, and nurse staffing). We included 16 studies, which showed few significant associations. Four hospital characteristics (higher hospital volume, higher nurse staffing, urban vs. rural status, and higher hospital financial resources) had statistically significant associations with lower mortality and selected IQIs in approximately half of the studies. For example, there were no associations between nurse staffing and four IQIs; however, approximately 50% of studies showed a statistically significant relationship between nurse staffing and lower mortality for six IQIs. For two hospital characteristics-higher bed size and disproportionate share percentage-all statistically significant associations had higher mortality. Five hospital characteristics (teaching status, system affiliation, ownership, minority-serving hospitals, and electronic health record status) had some studies with significantly positive and some with significantly negative associations, and many studies with no association. We found few associations between hospital characteristics and mortality IQIs. Differences in study methodology, coding across hospitals, and hospital case-mix adjustment may partly explain these results. Ongoing research will evaluate potential mechanisms for the identified associations.