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Caesarean sections and for-profit status
of hospitals: systematic review and
meta-analysis
Ilir Hoxha,
1,2
Lamprini Syrogiannouli,
2
Xhyljeta Luta,
1
Kali Tal,
1,2
David C Goodman,
1,3
Bruno R da Costa,
2
Peter Jüni
4
To cite: Hoxha I,
Syrogiannouli L, Luta X, et al.
Caesarean sections and for-
profit status of hospitals:
systematic review and meta-
analysis. BMJ Open 2017;7:
e013670. doi:10.1136/
bmjopen-2016-013670
▸Prepublication history and
additional material is
available. To view please visit
the journal (http://dx.doi.org/
10.1136/bmjopen-2016-
013670).
Received 29 July 2016
Revised 17 December 2016
Accepted 23 January 2017
1
Institute of Social and
Preventive Medicine,
University of Bern, Bern,
Switzerland
2
Institute of Primary Health
Care, University of Bern,
Bern, Switzerland
3
The Dartmouth Institute for
Health Policy and Clinical
Practice, Lebanon,
New Hampshire, USA
4
Applied Health Research
Centre (AHRC), Li Ka Shing
Knowledge Institute of St.
Michael’s Hospital,
Department of Medicine,
University of Toronto, Canada
Correspondence to
Dr Ilir Hoxha;
ilir.hoxha@ispm.unibe.ch
ABSTRACT
Objective: Financial incentives may encourage private
for-profit providers to perform more caesarean section
(CS) than non-profit hospitals. We therefore sought to
determine the association of for-profit status of
hospital and odds of CS.
Design: Systematic review and meta-analysis.
Data sources: MEDLINE, EMBASE and the Cochrane
Database of Systematic Reviews from the first year of
records through February 2016.
Eligibility criteria: To be eligible, studies had to
report data to allow the calculation of ORs of CS
comparing private for-profit hospitals with public or
private non-profit hospitals in a specific geographic
area.
Outcomes: The prespecified primary outcome was the
adjusted OR of births delivered by CS in private for-
profit hospitals as compared with public or private
non-profit hospitals; the prespecified secondary
outcome was the crude OR of CS in private for-profit
hospitals as compared with public or private non-profit
hospitals.
Results: 15 articles describing 17 separate studies in
4.1 million women were included. In a meta-analysis of
11 studies, the adjusted odds of delivery by CS was
1.41 higher in for-profit hospitals as compared with
non-profit hospitals (95% CI 1.24 to 1.60) with no
relevant heterogeneity between studies (τ
2
≤0.037).
Findings were robust across subgroups of studies in
stratified analyses. The meta-analysis of crude
estimates from 16 studies revealed a somewhat more
pronounced association (pooled OR 1.84, 95% CI 1.49
to 2.27) with moderate-to-high heterogeneity between
studies (τ
2
≥0.179).
Conclusions: CS are more likely to be performed by
for-profit hospitals as compared with non-profit
hospitals. This holds true regardless of women’s risk
and contextual factors such as country, year or study
design. Since financial incentives are likely to play an
important role, we recommend examination of
incentive structures of for-profit hospitals to identify
strategies that encourage appropriate provision of CS.
INTRODUCTION
Caesarean section (CS) has greatly improved
perinatal outcomes by reducing newborn and
maternal mortality,
1
but the increasing fre-
quency of CS has raised concerns, particularly
when performed in the absence of clear-cut
medical indications.
23
Organisation for
Economic Co-operation and Development
(OECD) data reveal an average annual
increase of 0.66% in member countries,
4
and
similar trends are evident elsewhere.
2
A recent analysis of national CS rates found
that rates up to 19% were inversely correlated
with maternal and neonatal mortality.
5
Many
countries have CS rates higher than 19%,
even though there is no evidence to suggest
that higher rates are associated with further
decreases in maternal and neonatal mortal-
ity.
56
In Brazil, for example, CS rates are esti-
mated at 46%.
7
Higher CS rates increase the
cost of care
38
and may have negative effects
on the health of mothers
9
and newborns.
10
CS rates vary considerably across regions
and hospitals within countries, and a closer
look at this variation may help to identify
factors that contribute to higher than neces-
sary rates.
2
CS receive higher reimbursement
than normal vaginal births in most health-
care systems.
11 12
We therefore hypothesised
that financial incentives encourage private
Strengths and limitations of this study
▪Major strengths of our meta-analysis include a
broad literature search, screening and data
extraction performed in duplicate, careful exclu-
sion of studies with overlapping populations and
an exploration of study characteristics as a
potential source of variation between studies.
▪A major limitation of our meta-analysis lies in
the variation between studies in design, number
of hospital units involved, size and character-
istics of study population, type of data used,
outcome measure and variables used in statis-
tical analysis. Despite these differences, the
results of the meta-analysis of adjusted estimates
were surprisingly consistent.
Hoxha I, et al.BMJ Open 2017;7:e013670. doi:10.1136/bmjopen-2016-013670 1
Open Access Research
providers with an emphasis on profit to perform more
CS than non-profit hospitals, and conducted a systematic
review and meta-analysis to determine the association of
for-profit status with the odds of delivery by CS.
METHODS
Data sources
We searched MEDLINE, EMBASE and the Cochrane
Database of Systematic Reviews from inception to 8
February 2016, when the search was last updated. We
combined search terms referring to CS, such as ‘opera-
tive delivery’,‘C section’,‘Cesarean’,‘Cesarean delivery’,
with search terms related to the design of studies such
as ‘small area analysis’,‘medical practice variation’, and
search terms related to determinants of variation and
increase of CS rates. We did not restrict searches by type
of language or publication date. Full details are given in
online supplementary appendix 1. In addition, we
manually searched the reference lists of all included
studies and earlier systematic reviews that we identified.
Study selection and outcomes
To be eligible studies had to report data to allow the cal-
culation of ORs of CS comparing private for-profit hospi-
tals with public or private non-profit hospitals in a
specific geographic area. The prespecified primary
outcome was the OR of births delivered by CS in private
for-profit hospitals as compared with public or private
non-profit hospitals adjusted for confounding factors as
specified by individual investigators. The prespecified
secondary outcome was the crude OR of CS in private
for-profit hospitals as compared with public or private
non-profit hospitals. Studies were included if they
reported data on either primary or secondary outcome.
Data extraction
Two researchers (IH and XL) screened the papers and
extracted data independently. Articles that were not pub-
lished in English were reviewed by authors with knowl-
edge of those languages. Differences were resolved by
consensus. Data from full-text articles were extracted
onto a data extraction sheet designed to capture data on
study population (history of previous CS, parity, risk
factors for CS, characteristics of newborn), study design
(size, sampling strategy, cross-sectional vs retrospective
cohort study), data sources (birth registries, hospital
records, surveys, insurance claims or census data),
setting (country and period of data collection), type of
CS analysed (indication for CS established before labour
(ie, planned), indication for CS established during
labour, any CS irrespective of indication) and statistical
analysis (including variables adjusted for). We extracted
adjusted and/or unadjusted ORs of CS in private for-
profit hospitals as compared with CS in public or private
non-profit hospitals.
Analysis
We used standard inverse-variance random-effects
meta-analysis to combine ORs overall and stratified by
type of reference group (ie, public or private non-profit
hospitals). An OR above 1 indicates that CS are more
frequently performed in private for-profit hospitals than
in public or private non-profit hospitals. We calculated
the variance estimate τ
2
as a measure of heterogeneity
between studies.
13
We prespecified a τ
2
of 0.04 to repre-
sent low heterogeneity, 0.16 to represent moderate and
0.36 to represent high heterogeneity between studies.
14
We conducted analyses stratified by study design (cross-
sectional vs retrospective cohort study), national CS rates
(moderate, high, very high), period of data collection
(up to 1994, between 1995 and 2004, 2005 and later),
parity (primiparae and multiparae combined vs prim-
iparae only), history of previous CS and type of CS ana-
lysed (indication for CS established before labour (ie,
planned CS), indication for CS established during
labour, any CS irrespective of indication) to investigate
potential reasons for between-study heterogeneity and
used χ
2
tests to calculate p values for interaction, or tests
for linear trend in case of more than two ordered strata.
National CS rates were classified into moderate (>15%
to 20%), high (>20% to 40%) and very high (>40%)
based on data reported by the WHO.
5
All p values are
two-sided. We used STATA, release V.13, for all analyses
(Stata-Corp, College Station, Texas, USA).
Patient involvement
No patients were involved in this study.
RESULTS
A total of 1621 records were identified by our search
(figure 1): 886 from MEDLINE: 494 from EMBASE; 221
from the Cochrane Database of Systematic Reviews and
20 from manual search. After removing duplicates, we
screened 1397 records for eligibility, retained 373
records for a more careful examination of titles and
abstracts, and excluded another 221 records because
they failed to match eligibility criteria. We assessed the
full texts of the 152 remaining records and excluded
another 113 that did not report private status of hospital,
21 that were otherwise irrelevant and 3 studies that had
an overlapping population. This left us with a total of 15
articles describing 17 separate studies in 4.1 million
women that were included in review and meta-analysis.
Characteristics of studies and populations are pre-
sented in table 1 and online supplementary appendices
2–4. Fifteen studies were cross-sectional, and two were
retrospective cohort studies. All studies were published
in English, except for one study in French. Most studies
were from France (4) and the USA (4). Exclusion cri-
teria varied considerably: 4 studies excluded girls aged
14 or below, 3 excluded multiparas, 7 excluded women
with previous CS, 13 excluded stillbirths and multiple
births, 5 excluded cases with specific presentations of
2Hoxha I, et al.BMJ Open 2017;7:e013670. doi:10.1136/bmjopen-2016-013670
Open Access
the fetus, and 5 studies excluded cases with other high
risk factors for CS; 15 studies excluded preterm births.
Twelve studies included the entire population of eligible
cases, while five studies selected cases randomly. Seven
studies used surveys, nine hospital records, four birth
registries, two insurance claims and one census data.
Five studies reported ORs of CS with indications estab-
lished before labour (including CS on maternal request)
only, 2 reported CS with indications estabished during
labour and 10 reported ORs of any CS. Online
supplementary appendix 4 presents the characteristics
that estimates were adjusted for. Among 11 studies
reporting adjusted estimates, the median number of
characteristics adjusted for was 8 (range 2–124).
Figure 2 presents the meta-analysis of the 11 studies
that reported adjusted ORs,
15–25
with 6 studies using
public non-profit hospitals as reference group, three
private non-profit hospitals and two using both. Overall,
the odds of receiving CS was 1.41 times higher in for-
profit hospitals as compared with either of the two types
of non-profit hospitals (95% CI 1.24 to 1.60), with no
relevant heterogeneity between studies (τ
2
≤0.037) and
little evidence for an interaction between estimated ORs
and type of reference group (p for interaction=0.20).
Figure 3 presents results of stratified analyses of adjusted
ORs. Estimates varied to some extent between strata, but
all tests for interaction or trend across subgroups were
negative. Pooled estimates ranged from 1.20 to 1.62
across subgroups. There was little evidence to suggest
secular trends ( p for trend=0.13) or an association of
ORs with national CS rates (p for trend=0.18). Figure 4
presents the meta-analysis of crude ORs with
moderate-to-high heterogeneity between studies
(τ
2
≥0.179), a somewhat more pronounced average asso-
ciation (pooled OR 1.84, 95% CI 1.49 to 2.27) and
again little evidence for an interaction between esti-
mated ORs and type of reference group (p for
interaction=0.48).
DISCUSSION
Our systematic review and meta-analysis indicates that
the odds of receiving a CS are on average 1.4 times
higher in private for-profit hospitals than in non-profit
hospitals. Findings were robust across all subgroups of
studies in stratified analyses. In particular, there was little
evidence to suggest secular trends or an association with
national CS rates. Even though, a test for trend across
periods of data collection was negative, we found the
association between for-profit status of hospitals and
Figure 1 The flow diagram of
review.
Hoxha I, et al.BMJ Open 2017;7:e013670. doi:10.1136/bmjopen-2016-013670 3
Open Access
Table 1 Characteristics of included studies
Author Year Country Study design
Number of
cases
Number of
hospital units
Year of data
collection Population Sampling
Type of CS
analysed
National CS
rates*
Braveman et al 1995 USA Retrospective
cohort study
213 761 Unclear 1991 Primiparae; no previous CS;
any risk
Consecutive Any High
Naiditch et al 1997 France Cross-sectional 39 880 944 1991 Primiparae and multiparae;
no previous CS; any risk
Random Before labour Moderate
Gomes et al. A 1999 Brazil Cross-sectional 6750 8 1978–1979 Primiparae and multiparae;
with or without previous CS;
any risk
Consecutive Any Very high
Gomes et al. B 1999 Brazil Cross-sectional 2846 10 1994 Primiparae and multiparae;
with or without previous CS;
any risk
Consecutive Any Very high
Gonzalez-Perez
et al
2001 Mexico Cross-sectional 1 716 446 Unclear 1994–1997 Primiparae and multiparae;
with or without previous CS;
any risk
Consecutive Any High
Korst et al 2005 USA Cross-sectional 443 532 288 1995 Primiparae and multiparae;
no previous CS; any risk
Consecutive During labour High
Mossialos et al. 2005 Greece Cross-sectional 805 3 2002 Primiparae and multiparae;
with or without previous CS;
any risk
Consecutive Any High
Carayol et al A 2007 France Cross-sectional 1479 Unclear 1972, 1995,
1998, 2003
Primiparae and multiparae;
no previous CS; high risk
Random Before labour Moderate
Carayol et al B 2007 France Cross-sectional 6080 138 2001-2002 Primiparae and multiparae;
no previous CS; high risk
Random Before labour Moderate
Xirasagar and Lin 2007 Taiwan Cross-sectional 739 531 942 1997–2000 Primiparae and multiparae;
with or without previous CS;
any risk
Consecutive Before
labour†
High
Coonrod et al 2008 USA Cross-sectional 28 863 40 2005 Primiparae; low risk Consecutive Any High
Coulm et al 2012 France Cross-sectional 9530 535 2010 Primiparae and multiparae;
no previous CS; low risk
Consecutive Any Moderate
Huesch et al 2014 USA Cross-sectional 408 355 254 2010 Primiparae and multiparae;
no previous CS; any risk
Consecutive Before labour High
Raifman et al A 2014 Brazil Cross sectional 4918 Not Reported 1996 Primi- and multiparae; with
or without previous CS; any
risk
Random Any Very high
Raifman et al B 2014 Brazil Cross sectional 5768 Not Reported 2006 Primi- and multiparae; with
or without previous CS; any
risk
Random Any Very high
Schemann et al 2015 Australia Cross sectional 61 894 81 2007-2011 Multiparae; with previous CS Consecutive Any High
Sebastião et al 2016 USA Retrospective
cohort study
412 192 122 2004-2011 Primiparae; low risk Consecutive During labour High
*National CS rates classified according to WHO data reported for 2008 into moderate (>15% to 20%), high (>20% to 40%) and very high (>40%).
†On maternal request.
CS, caesarean section.
4Hoxha I, et al.BMJ Open 2017;7:e013670. doi:10.1136/bmjopen-2016-013670
Open Access
odds of CS less pronounced in recent years. In view of
the negative test for trend, this could be a chance
finding. Alternatively, this may reflect attempts of care
providers and policymakers to attenuate raising CS rates
over time.
Context
To our knowledge, this is the first meta-analysis to
address the association of CS rates with for-profit status
of hospitals. We are aware of three recent meta-analyses
that examined the association of CS rates with obesity,
26
ethnic origin
27
and labour induction.
28
In a
meta-analysis of unadjusted estimates from prospective
and retrospective cohort studies, Poobalan et al
26
found
a 53% increase in the odds of CS associated with mater-
nal overweight and a 126% increase with obesity. Merry
et al
27
found a 41% increase in the adjusted odds of CS
associated with sub-Saharan African origin, and a 99%
increase associated with Somali origin of women.
Estimates for South, North-African/West Asian and
Latin American women were similar but statistically not
significant. Finally, in a meta-analysis of randomised
trials, Mishanina et al
28
found expectant management to
be associated with a 14% increase in the risk of CS. Our
meta-analysis indicates agreement across 17 studies per-
formed in seven countries as to the direction of this
association, even though the magnitude of the associ-
ation shows some variability. Our pooled estimate of a
41% increase in adjusted odds of CS associated with for-
profit status of hospital has a similar or larger magnitude
than the associations found for the characteristics above
and therefore appears relevant for clinical and policy
decision-making.
Strengths and limitations
A major limitation of our meta-analysis lies in the vari-
ation between studies in design, number of hospital
units’involved, size and characteristics of study popula-
tion, type of data used, outcome measure and variables
used in statistical analysis. Despite these differences, the
Figure 2 Adjusted ORs of caesarean section.
Hoxha I, et al.BMJ Open 2017;7:e013670. doi:10.1136/bmjopen-2016-013670 5
Open Access
results of the meta-analysis of adjusted estimates were
surprisingly consistent. Conversely, unadjusted estimates
showed considerable heterogeneity between studies,
which suggests confounding by medical and non-
medical factors as a reason for variation between studies.
Among these factors are socioeconomic status, prefer-
ences and clinical condition of women, fetus character-
istics, medical care during pregnancy and delivery as
well as physician, hospital and health system character-
istics.
2
Professionals often attribute higher rates of proce-
dures to the gravity of clinical conditions of patient
receiving an intervention. This argument is not sup-
ported by the data of this review as associations of CS
rates with for-profit status were consistently found in ana-
lyses adjusted for a wide range of risk factors (see online
supplementary appendix 4). Major strengths of our
meta-analysis include a broad literature search, screen-
ing and data extraction performed in duplicate, careful
exclusion of studies with overlapping populations and
an exploration of study characteristics as a potential
source of variation between studies.
Mechanisms
Financial incentives are likely to contribute to the
observed association. The literature has described the
influence of supply factors in the type and amount of
care provided for a given condition.
29–32
Private for-
profit institutions may create financial incentive struc-
tures that encourage more resource-intensive
33
and
expensive procedures,
11 34–36
since that will increase
their profits. The payment model of hospitals and physi-
cians is another important factor.
11 32 34 35 37
Fee for
service reimbursement may be more common for
private for-profit hospitals and will encourage hospitals
and physicians to provide more procedures than medic-
ally indicated
38–40
and increase time pressure on physi-
cians to perform CS instead of waiting longer for a
normal birth.
41 42
Health insurers can also encourage
overprovision of CS as they tend to reimburse hospitals
and physicians better for CS than for vaginal deliv-
ery.
11 43 44
Finally, private for-profit institutions typically
have a higher number of qualified physicians, more
resources and better infrastructure,
23245–47
which will
Figure 3 Stratified analyses. *p Value for linear trend.
6Hoxha I, et al.BMJ Open 2017;7:e013670. doi:10.1136/bmjopen-2016-013670
Open Access
encourage overprovision of care in private for-profit
institutions.
Implications for research
Although immediate steps to improve clinical decision-
making for CS should not be delayed, further research
would inform the persistent dilemma of misalignment
between good care and financial incentives. Since finan-
cial incentives differ across and within countries, there is
a need for additional context-specific investigation of
the economic drivers of overuse.
48
Policy analysis focus-
ing on for-profit hospitals should examine further the
interplay of specific factors for each country or, ideally,
individual contracts between insurers and providers
within countries to identify financial incentives that
cause private for-profit hospitals to perform more CS
than non-profit hospitals. Such analyses should explore
if financial incentives interact at the physician level, such
as physician payment schemes, or at the hospital level,
including informal or formal pressure on physicians to
choose more expensive procedures or save time by per-
forming a CS instead of waiting longer for a normal
birth. In some countries, such analyses should also
extend to not for-profit hospitals, if fee for service pay-
ments are used regardless of for-profit status. The effects
of the level and type of government regulation of hospi-
tals, type of health insurance and implementation of
clinical guidelines also require further study.
Implications for policymaking
The persisting increase of CS rates in many health systems
despite the growing recognition of CS overuse suggests that
current clinical guidelines are not sufficient.
2
Improving
clinical decision-making by providing clear clinical guide-
lines that are evidence based would be one step forward.
Equally important is the alignment of financial incentives
with the objective to improve care without increasing costs.
The higher odds of CS in the for-profitsectorsuggestthat
Figure 4 Crude ORs of caesarean section.
Hoxha I, et al.BMJ Open 2017;7:e013670. doi:10.1136/bmjopen-2016-013670 7
Open Access
physicians and hospitals are responsive to financial incen-
tives. Changing reimbursement policies so that vaginal
deliveries and CS are paid similarly could keep overall pay-
ments to physicians and hospitals approximately constant
without encouraging unnecessary CS but will not guaran-
tee an elimination of overuse. Negative incentives, such as
penalising hospitals for high CS rates could also be consid-
ered, but require monitoring for unintended conse-
quences.
49
A decrease of unnecessary CS, a cost-effective
use of resources and improved health outcomes for
mothers and newborns should be the ultimate goal.
CONCLUSION
This systematic review and meta-analysis indicates that
CS are more likely to be performed in for-profit hospi-
tals as compared with non-profit hospitals. This holds
true regardless of women’s risk and contextual factors
such as country, year or study design. Since financial
incentives are likely to play an important role, we recom-
mend examination of incentive structures, including
reimbursement schemes of for-profit hospitals, to iden-
tify strategies that encourage best clinical judgement and
outcome rather than rewarding expensive procedures
that are clinically unnecessary and potentially harmful
for mothers and newborns.
Contributors IH, DCG and PJ have developed the idea for the study. IH, XL
and DCG were involved in the study conception, preliminary literature review
and design of the search strategy and the study protocol. IH, LS and XL were
involved in screening and data extraction of papers. All authors reviewed data
extraction output. IH, LS, BRdC and PJ designed and performed the
meta-analysis. IH, LS, KT, BRdC and PJ drafted the report, which
was critically reviewed and approved by all authors.
Funding This research received no specific grant from any funding agency in
the public, commercial or not-for-profit sectors.
Competing interests None declared.
Provenance and peer review Not commissioned; externally peer reviewed.
Data sharing statement No additional data are available.
Open Access This is an Open Access article distributed in accordance with
the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license,
which permits others to distribute, remix, adapt, build upon this work non-
commercially, and license their derivative works on different terms, provided
the original work is properly cited and the use is non-commercial. See: http://
creativecommons.org/licenses/by-nc/4.0/
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