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Budget impact of a program for safely reducing caesarean sections in Canada
Clara Bermúdez-Tamayo, Mira Johri, Nils Chaillet
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Budget impact of a program for safely reducing caesarean sections in Canada
Clara Bermúdez-Tamayo, MPH PhD 1,2,3,* Professor
Mira Johri, PhD4,5. . Professor
Nils Chaillet, PhD6 Professor
1 Centre de recherche du CHUS, 12e Avenue Nord, Sherbrooke, QC J1H 5 N4, Canada
2 Andalusian School of Public Health, Cuesta del Observatorio 4, 18010 Granada, Spain
3 CIBERESP, Ciber de Epidemiologia y Salud Publica, Madrid, Spain
4 Division of Global Health, University of Montreal, Hospital Research Centre (CRCHUM), 900, rue Saint-Denis, H2X 0A9 Montreal, QC, Canada
5 Department of Health Administration, School of Public Health, University of Montreal, Montreal, QC, Canada
6 Centre Hospitalier de l'Université Laval (CHUL), Québec, Canada
* Corresponding author. Andalusian School of Public Health, Cuesta del Observatorio 4, 18010 Granada, Spain. Email: [email protected]
Abstract
Introduction: Audits of indications for cesarean section (CS), feedback for health professionals, and implementation of best practices, as compared with usual care (QUARISMA study), resulted in a small reduction in the rate of CS in Quebec and important cost savings from a health care payer perspective.
Determining the budget impact would enable estimation of the financial consequences if the program is extended nationwide.
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Material and methods: A retrospective pre-post study design was used to estimate cost prior to and after the implementation of QUARISMA in Quebec (105,351 subjects). A prospective analysis was performed to measure the budget impact in Canada’s provinces. The primary analytic perspective was that of the Minister of Health, for a 4-year time horizon. Data were taken from the trial for Quebec and extrapolated to Canada’s provinces. A sensitivity analysis was conducted by varying more than one probability at a time.
Results: Over 4 years, there was a decrease of more than $7.8 million in CS burden in Quebec, $11.9 million in vaginal birth and $9.8 million for neonatal complications. The impact on high-risk women was lower than that on low-risk. In years 1 and 2, the provinces would have to cover the cost of program implementation.
Conclusions: QUARISMA led to savings of $27 million in Quebec over 4 years. In the short to medium term, extending the QUARISMA program nationwide could lead to savings of $150.5 million.
Keywords: caesarean section, clinical practice guidelines, budget impact analysis.
Abbreviations
CS: Caesarean section
BIA: Budget impact analysis
Introduction
Considering the increasing growth in health care costs, and the budgetary constraints in many countries, it seems crucial to analyze technologies or procedures with a probable margin of inefficiency that may have a significant impact on budgets (1). Giving birth is the most common reason for hospitalization in developed countries (2,3). In Canada, vaginal births and CS accounted for 15% of all inpatient hospitalizations, and represents, in the aggregate, one of the most costly conditions for inpatient hospital care (3). In 2015, more than one in four births in hospital was by CS, an increase of nearly 10% since 1995 (4). The rapid increase
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in the rate of CS births without evidence of concomitant decreases in maternal or neonatal morbidity raises concerns that CS is overused (5). Because of potential harm to mother and baby associated with medically unnecessary CS (6), and given that CS can be up to 45% more expensive than a vaginal birth (7), improvements could be made to enhance efficiency.
In response to the rise in CS rates across Canada, in 2008 the Society of Obstetricians and Gynaecologists (SOGC) released a joint policy statement aimed at reducing unnecessary CS and promoting normal childbirth whenever possible (8). However, these recommendations have remained quite general and decisions to opt for CS continue to be discretionary and often based on non-medical factors (9). The QUARISMA project was designed to make progress in this area (10). It was a randomized controlled trial to reduce the rate of CS with self-assessment of practice by peers. The project hypothesizes that poor adherence to clinical practice guidelines (CPGs) plays a key role in the rising CS rate. The QUARISMA program results suggest that a multifaceted intervention with clinical audit, feedback activities and best practice implementation may contribute to a small to moderate reduction in the overall cesarean delivery rate, with a marked reduction in low-risk women, and an overall improvement in neonatal outcomes (11).
Furthermore, the cost-effectiveness analysis showed that the intervention resulted in important cost savings from a health care payer perspective (12).
The potential implementation of such a program by the health care system must be analyzed based on efficiency. Budget impact analysis (BIA) would enable estimation of the financial consequences of extending the program nationwide in Canada in the short to medium term (12).
MATERIAL AND METHODS
A retrospective pre-post study design was used to estimate cost prior to and after the implementation of the QUARISMA trial in Quebec (Canada). We also performed a prospective analysis of the potential economic impact of program implementation in Canada’s other provinces. The methodology is described according to the framework proposed by the BIA good practice guidelines (13).
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Patient population
For the retrospective analysis for Quebec, we included 105,351 women enrolled in the QUARISMA study and treated in 32 centres. 47,872 were assigned to QUARISMA and 57,479 to standard care.
For the prospective analysis, we considered annual births in the provinces and territories of Canada. We included Alberta, British Columbia, Manitoba, New Brunswick, Newfoundland and Labrador, Northwest Territories, Nova Scotia, Ontario, Prince Edward Island, Saskatchewan and Yukon Territory (Table 1). The territory of Nunavut was excluded because of demographic differences and differences in clinical practice in comparison with Quebec. It had by far the lowest cesarean section rate (less than 10% of all deliveries).
This low rate can be attributed at least partly to a much younger average age of mothers at childbirth, reducing the risk of a cesarean section, as well as cultural aspects of women and doctors (9).
Intervention mix
QUARISMA program: The program combines the training of professionals and local opinion leaders with
best practices, as well as technical audit of CS and the implementation of audit recommendations. The audit process focuses on factors relating to structure (organizational factors affecting adherence to CPGs), the care process (review of records of CS, interviews with women) and outcomes (statistics for CS rates and morbidity). The program phases and activities are described below and schematized in Figure 1.
a. Identification and training of opinion leaders, members of the audit committee and data collectors.
The program was implemented in hospitals over a period of 6 months. A local audit committee and a local team were identified in each of the centres receiving the intervention.
The members of the audit committee received 2 days of training on technical auditing and best practices in each hospital. A recertification day was held at the beginning of year 3. The entire training program was run by the SOGC. The training program focused on 4 main indications for CS, based on: 1) SOGC CPGs on induction of labor at term, monitoring of fetal well-being during labor, vaginal delivery and operative
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vaginal delivery in women with a previous CS (1 day); 2) a workshop dedicated to reviewing the studies on maternal and perinatal morbidity associated with each mode of delivery (half day); and 3) participant training in audit techniques (half day). The program also raised awareness of the social, economic, cultural and legal factors contributing to the increase in CS rates. The data collectors received 2 days of training on data collection and analysis of data necessary for the audit process.
b) Implementation of audit cycles. After the implementation period of 6 months, four 3-month audit cycles
were set up for 1 year. Each cycle was divided into 5 phases according to a standardized procedure: 1) organize 4 audit cycles for a period of 3 months each; 2) complete audit records for each case; 3) draw up recommendations; 4) ensure their implementation; 5) write up a report summarizing the results. During the post-intervention phase, continuing audits of CS cycles (without supervision) were encouraged in each centre, to assess the sustainability of the program. A meeting to present the results was held at the end of the year post-procedure.
Control group: No external intervention was planned in this group. However, internal evaluation activities and supervision are part of standard practice in hospitals and were not an exclusion criterion.
Time horizon and perspective
- Retrospective analysis in Quebec. The time horizon included is shown in Figure 1. The first year was the ‘pre-intervention’ period, to prepare and update the guidelines. There was then a 1.5-year intervention period and a 1-year post-intervention period.
- Prospective analysis in Canada. The budget impact was calculated for a 3-year time horizon. We included the pre-intervention period as part of the first year, prior to the intervention.
The primary analytic perspective was that of the Minister of Health.
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Resource use and costing
The resources used by women giving birth were taken from the trial for Quebec (9) and extrapolated to Canada’s provinces. We considered: 1) Cost of the program, including training, audits and recertification;
2) Cost per woman giving birth and baby. We studied only the resources where significant differences were found in the trial (9).
The use of resources per patint (women giving birth and baby), is divided into 3 categories: related to the intervention, to the birth and to complications. The observation period of the post-intervention phase begins at the women’s admission to hospital at onset of spontaneous labour, and lasts until discharge.
Data sources
The source for the hospital unitary cost was the Patient Cost Estimator, developed by the Canadian Institute for Health Information (CIHI) (14) to estimate the average cost of various services provided in hospitals. It provides information by jurisdiction and by patient age group. The cost estimates represent the estimated average cost of services provided to the average patient. The fees were taken from the National Physician Database (15).
We used the following costs (taking into account mother age; <18 years or >=18 years):
- Associated with caesarean section: primary CS with induction, primary CS no induction, CS with uterine
scar and no induction, CS with uterine scar and induction, CS multiple birth.
- Vaginal birth (VB) after caesarean: VB with anaesthetic and non-major obstetric/gynecological (OB/GYN) intervention, VB with anaesthetic without non-major OB/GYN intervention, VB without anaesthetic with non-major OB/GYN intervention, VB without anaesthetic without non-major OB/GYN intervention.
- Assisted vaginal delivery: VB with anaesthetic with non-major OB/GYN intervention, VB without anaesthetic with non-major OB/GYN intervention.
- Labour induction.
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- Procedures for the neonate: transient tachypnea; newborn major respiratory complication, respiratory
insufficiency or distress syndrome; newborn major respiratory complication, cardiopulmonary resuscitation; newborn aspiration syndrome/fetal asphyxia; subdural haematoma; newborn other major problem including intracerebral or intraventricular haemorrhage, spinal cord injury, basal skull fracture;
newborn 2500+ grams, other moderate problem; brachial plexus injury/palsy and peripheral nerve injury.
Supplementary appendix shows the range of total unitary costs for the different resources in Quebec and Canada used in the study.
Analysis
The budget impact was calculated by demonstrating the resulting total costs for the QUARISMA program compared with the alternative ‘standard practice’ in Quebec. As a final result, savings or extra costs were displayed for each year, separately according to the women’s risk category. Risk status was considered on the basis of literature reviews and the consensus of experts from the QUARISMA research team (9). A pregnancy was considered at low-risk if the woman gave birth to a single baby in cephalic presentation, with no prior or current assisted reproductive technology, a maternal age ≥ 18 and < 40 yr, a gestational age
≥ 37 and < 42 weeks, a body mass index ≥ 17 and < 30, and no prior cesarean delivery, no prior or current stillbirth, no in utero transfer in another hospital, and no other pathology or complication during current or prior pregnancy. A pregnancy was considered at risk if any of the above conditions was not met.
Pathology or complication during pregnancy: Non-cephalic presentation of the baby (including post-version cephalic presentation), premature detachment of normally implanted placenta, myomectomy, uterine rupture, pre-eclampsia, eclampsia, gravidic gestational hypertension, cardiac, Crohn, thrombophilia or kidney disease, systemic lupus erythematosus, pre-existing diabetes, gestational diabetes, infectious disease (hepatitis, herpes, AIDS, malaria, pyelonephritis), thyroid disorders, placenta previa, premature rupture of membranes (women < 37 weeks), incompatibility Rh/ABO, intra uterine growth restriction (IUGR), drugs abuse and birth defect (congenital anomalies or malformation).
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Those results were extrapolated to all the provinces of Canada to calculate the potential savings or extra costs by year. The calculation was replicated in a Microsoft Excel-based spreadsheet model, which serves as a flexible analytic tool to examine the budgetary impact of QUARISMA.
Uncertainty
To test the levels of uncertainty in the estimates, a sensitivity analysis was conducted by varying more than one probability at a time. The following factors were varied: program costs, CS cost, VB costs, CS rate, complications. The extreme scenario occurs when all the variables have the highest value at a time.
It is assumed that the target population will hold stable over the time horizon for two reasons. Firstly, the birth rate has not shown a clear upward or downward trend over recent years. Secondly, we assumed there would not be any major lifestyle changes during the following 4 years.
Results
The 4-year results from the BIA in Quebec are shown in Table 2. Over 4 years, the savings to the Ministry of Health in Quebec were more than $27 million.
The total cost of deliveries was $1,088.5 million for the intervention group and $1,108.3 million for the control group. This is a reduction of more than $19 million in the deliveries budget, attributable to the QUARISMA program in Quebec.
According to the mode of birth, there was a decrease of more than $7.8 million in cesarean burden ($335.4 million for intervention vs. $343.3 million for control group) and a decrease of $11.9 million in vaginal birth burden ($753.1 million for intervention vs. $765.1 million for control group).
Regarding complications, spending decreased by $9.8 million in the intervention group in comparison with the control group ($2.8 million for major trauma, $7.5 million for cardiopulmonary morbidity and $0.6 million for non-invasive mechanical ventilation).
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The total cost by year of the QUARISMA intervention in Quebec is shown in supplementary Appendix 1.
It includes pre-intervention costs of $29,594 in the first year (to prepare and update the clinical guidelines), an implementation cost of $198,498, for training in the first 2 years and recertification in the third year, as well as activities conducted over the entire period, including SOGC training ($502,106) and local audit committees ($1.2 million). Finally, there were other activities related to data collection and management, costing $627,910 (surveillance and coordination, training of data gatherers and IT data management). The total cost of the intervention was $2.5 million in Quebec, for all of the 4 years considered.
The 4-year results from the BIA in Quebec are shown in Table 3 for the intervention and control group, separately for women at low/high risk.
For women at low risk, the total cost of delivery for the intervention group in Quebec was $547.1 million.
The total cost of delivery for the control group was higher ($558.7 million). The complications costs were lower for the intervention group in comparison with the control group ($73.8 million vs $93.6 million), including major trauma ($14.3 million vs. $15.0 million), cardiopulmonary morbidity ($56.6 million vs.
$61.6 million) and non-invasive mechanical ventilation ($2.8 million vs. $3 million).
For women at high risk, there were differences between the intervention and control groups, but these differences were smaller than those in low-risk women. The total cost of delivery for the intervention group in Quebec was $541.4 million. The cost for the control group was higher ($549.7 million). The complications costs were slightly lower for the intervention group in comparison with the control group, including major trauma ($12.6 million vs. $14.8 million), cardiopulmonary morbidity ($76.6 million vs.
$77.3 million) and non-invasive mechanical ventilation ($ 3.5 million vs. $2.7 million).
Table 4 shows the savings resulting from the QUARISMA program. Savings were higher in the low-risk group than in the high-risk group. In the low-risk group, the program resulted in a spending decrease of
$16.0 million, of which $11.5 million were saved in deliveries (with a decrease of $11.3 million in CS and
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$213,010 in VB), and $5.8 million were saved in neonatal morbidity ($721,024 for major trauma, $4.9 million for cardiopulmonary morbidity and $117,529 for non-invasive mechanical ventilation).
In the high-risk group, the program led to savings of $11.0 million, of which $8.2 million were saved in deliveries (with an increase of $3.5 million in CS and a decrease of $11.7 million in VB) and $4.0 million was saved in neonatal morbidity ($2.1 million in major trauma, $2.6 million in cardiopulmonary morbidity and $723,372 in non-invasive mechanical ventilation).
The prospective budget impact of the QUARISMA intervention nationwide is shown in Table 5. Over 4 years, the savings to Canada would be $150.5 million. In years 1 and 2, the provinces would have to cover the cost of program implementation. In year 3, the intervention cost would be lower ($3 million), with savings of $37.9 million in deliveries and $24.4 million in neonatal morbidity. In year 4, the intervention cost would be lower than in year 3 ($2.6 million), with savings of $65.1 million in deliveries, and $35.0 million in neonatal morbidity.
The results of the sensitivity analyses are shown in Figure 2. The tornado diagram shows that the results of the model are particularly sensitive to VB cost. The absolute budget impact ranged from -$21 million to
$42 million for Quebec in 4 years.
Discussion
One of the major debates in public funding of research is its overall return to society (16,17). Studies like this one, that link public-sponsored research to changes in clinical practice patterns, patient outcomes and costs, are uncommon. Our study findings suggest that public research investments can yield clinical and economic value when targeted to address research questions with great clinical relevance and public health impact. Such information can inform the debate about the role of publicly funded medical research in the nation’s portfolio of provincial health spending.
The current cesarean delivery rate puts increasing economic and human resource demands on our already
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challenged system. This study shows that childbirth is a promising area to control part of the budget of the Ministry of Health in Quebec and across Canada’s provinces, since there is a significant gap to bridge to achieve an acceptable CS rate. A World Health Organization study group suggested no additional benefits were associated with rates higher than 10-15% and proposed an empirical threshold in the intensity of use, suggesting that ‘countries with C-section rates above 15% were considered to show overuse’ (18,19).
According to the literature (20-23), drivers of the intensity of utilization might ostensibly lie on the supply side, relating to provider density, the capacity of the local health care system, malpractice pressure, management of induced labour and quality of obstetric care. All of them are susceptible to intervention by decision-makers in order to realign providers’ incentives to deliver value-based care. According to systematic reviews, interventions related to guidelines and addressed to physicians could be effective to decrease CS, as well as giving individualized information to women (24,25). A strategy to engage consumer-oriented media would contribute to better understanding and decision-making by the public and could have an important budgetary impact, as this study does.
There is a clear need to generate tools and shape solid analytical methods that could support decision-making in optimizing the use of available resources (26). Reimbursement authorities increasingly utilize BIA not only to calculate affordability, but for advocacy and awareness among health decision-makers.
There are variations in professionals who attends births between provinces of Canada. The majority of births (72%) are attended by obstetricians, 25% by family physicians, and 3% by midwives (3). Because QUARISMA intervention was addressed to obstetricians and family physicians, impact of intervention and budget impact was more limited in those provinces as British Columbia or Ontario, where midwives attend births in 21% and 15 %, respectively.
As with all models, the main limitation of this budget impact model was the simplification of assumptions required to compare the QUARISMA intervention with standard practice. First, we considered that the program would ensure the same results in different contexts. Research in Canada has shown that CS rates
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vary considerably between regions (21,22), and this could suggest that there are certain differences in practices and that some of the variation may be attributable to providers and/or women preferences.
According to the Canadian Hospitals Maternity Policies and Practices Survey (27), there are certain similarities in hospital policies and directives that should allow implementation of the program. For example, most hospitals have policies specifying routine initial electronic fetal heart rate monitoring on all women (74%), a policy regarding induction of labour (89%), ambulation available for pain control (99%) and epidural anesthesia available for pain control (87%). Furthermore, most hospitals in Canada (84%) have a perinatal committee that reviews obstetrical policies and approves guidelines.
The second limitation is related to the costs included in our analysis. The estimation of costs has been conservative. For example, we only considered the observation period of the post-intervention phase, from the women’s admission to hospital at onset of spontaneous labour to discharge. According to the American College of Obstetricians and Gynecologists (28), in most cases the complications associated with delivery occur before discharge. We excluded any complications that occurred in mother and baby after discharge, as well as the health problems derived from previous complications. This probably influences the results for the group with a higher CS rate, i.e. the control group. We also did not include the cost of subsequent CS. Even if a previous CS is no longer considered an indication per se to perform a planned cesarean in the second pregnancy, it is well known that women with a first CS are at increased likelihood of a repeat cesarean (29). In this case, our results are also biased against the intervention.
Thirdly, the cost savings need to be interpreted with caution, because existing infrastructure and personnel cannot immediately be reduced if CS and complication rates decrease.
Finally, the alternative scenarios chosen (‘standard practice’) may not totally reflect the real-world situation in Canada as many of the measures analyzed may already have been implemented in some cases, such as the provincial perinatal programs: Perinatal Program of Newfoundland and Labrador, British Columbia Perinatal Health Program, Child Health Network - Greater Toronto Area, Champlain Maternal Newborn Regional Program (CMNRP), Reproductive Care Program of Nova Scotia, Alberta Perinatal, Southwestern
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Ontario Maternal, Newborn, Child and Youth Program, and Saskatchewan Perinatal Education Program.
This influences the results in two directions.
In keeping with the theory of change for the QUARISMA intervention, which attempted to optimize medical practice by reducing unnecessary caesareans, our study found evidence of improved quality along the continuum of care. Cost reductions were driven principally by lower rates of neonatal complications and corresponding lower use of resources within the intervention group. These changes are consistent with improvements in the quality of care in intervention group hospitals (10). Findings from our study provide new evidence concerning a safe and possibly sustainable strategy to reduce unnecessary caesarean sections at wider scale and cost savings over time.
Funding statement:
Supported by grants from the Canadian Institutes of Health Research (200702MCT-171307-RFA-CFCF-153236 and MOP 81275), and the Spanish Ministry of Health and Consumer Affairs (FIS Exp.
PI13/01340).
Conflicts of Interest notification:
None declared
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