The REDUCED Trial: REDucing the Utilization of CEsarean Sections for Dystocia
Phase: NA
Conditions: Cesarean Section, Dystocia
Sponsor: University of Calgary

 
 
The REDUCED Trial: REDucing the Utilization of CEsarean sections for Dystocia  
 
Primary Investigators: Dr. Stephen Wood, Dr. Amy Metcalfe 
 
Protocol ID – REB16-1576 
 
November 8, 2023 
 

 
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TABLE OF REVISIONS 
 
Version 
Date of revision 
Comments 
1 
May 31, 2017 
- 
Original protocol 
2 
Sept 8, 2018 
- 
Clarified that our study population includes primiparous 
women “at term (≥37 weeks), with a vertex presenting 
singleton fetus” 
- 
Provided an updated definition for neonatal asphyxia 
- 
Updated this paragraph of the statistical analysis: “The 
intervention period for the study will be taken as starting 
with the first day of roll-out (initiation complete at that site) 
of the guidelines until the completion of the program at all 
sites, with baseline and post-intervention encompassing the 
two year and four year periods before and after. The 
primary analysis will be performed on data for the period of 
time from completion of all site initiation (December 1 2017, 
until a 2 year period has expired from the initiation of the 
final intervention site (November 30th 2019). A subsequent 
4 year analysis is also planned for data up to November 30th 
2021. Occurrence of CS will be assessed over baseline and 
post-intervention using a repeated mixed effects logistic 
regression model following a constrained baseline approach 
which confines group differences to the post-intervention 
period, assuming no systematic difference during the 
baseline period. The random effects will include site and 
period within site. Having fewer than 40 sites, a small 
sample correction will be applied to the standard error for 
group differences underlying significance tests and 
confidence interval construction. As a secondary analysis, 
we will include data from the intervention period reflecting 
the site-specific dates for completion of the intervention (1st 
site completed initiation Feb 1 2017), incorporating a linear 
time trend to accommodate the potential for confounding of 
an underlying secular trend.” 
3 
April 25, 2019 
- 
Added labour culture survey methodology. 
- 
Added three secondary outcomes, including: postpartum 
uterine artery/pelvic artery embolization; postpartum 
hysterectomy; and postpartum maternal intensive care unit 
(ICU) admission. 
- 
Added this statement to the statistical analysis: “The model 
will include year and treatment plus treatment by year 
interaction over the intervention period, with corresponding 
random effects by site”. 
4 
August 12, 2019 
- 
Added the 2014 ACOG/SMFM guidelines. 
- 
Added methodology regarding chart review to determine the 
percentage of cesarean sections for dystocia that were done 
following the ACOG/SMFM guidelines 
5 
February 3, 2020 
- 
Changed the dates for the chart review from a one-year period 
from Dec 1, 2018 to Nov 30, 2019, to a two-year period from 
Dec 1, 2017 to Nov 30, 2019. 
- 
Updated the statistical analysis section: 
“The primary analysis will include individual level data from 
all sites from the baseline period (2015 to 2016) and follow-
up thereafter in both arms. The intervention period will 
defined separately for each intervention site according to the 
date of completion of implementation of the program (which 

 
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Version 
Date of revision 
Comments 
varied for the 13 intervention sites from January 31, 2017 to 
November 30, 2017).  Data from the implementation phase 
(nominally one to two months) will be excluded as a wash-
out period. The first intervention period ends November 30, 
2019 (two years after completion of site initiation at all 
intervention sites), and the second intervention period will 
end November 30, 2021 (four years after completion of site 
initiation).  
CS rates will be assessed using repeated measures mixed 
effects logistic regression applied to individual births.  We 
will apply a constrained baseline approach to adjust for pre-
intervention data.  Explanatory variables (fixed effects) in 
the model will include time period (in 6 month intervals), 
and indicators for intervention and post-intervention phases 
in the intervention sites. The post-intervention parameter 
will represent the primary measure of efficacy. 
Corresponding site-specific random effects will be included 
for all fixed effects”. 
- 
Note that the statistical analysis section was updated prior 
to the study team receiving the final data for the trial.  
6 
April 27, 2020 
- 
As a result of the COVID-19 pandemic, the REDUCED Trial 
was ended on Feb 29, 2020 (i.e. prior to the WHO declaring 
COVID-19 as a global pandemic on March 11, 2020), instead 
of Phase 1 being ended on Nov 30, 2019 and Phase 2 being 
ended on Nov 30, 2021. See Appendix 1. 
- 
Note that this change was made prior to the study team 
receiving the final data for the trial. 
- 
Changes in dates in the protocol are bolded. 
7 
July 23, 2020 
- 
Added obstetrical chart review of stillbirth cases from Jan 
2018 to Feb 2020. 
8 
Feb 3, 2023 
- 
Added details of the revised Phase 2 analysis (changes in red 
on page 10). 
9 
Nov 8, 2023 
- 
Clarified details of the revised Phase 2 analysis to extend to 
the date that the Society of Obstetricians and Gynaecologists 
of Canada (SOGC) changes their labour management 
guidelines to reflect the ACOG/SMFM guidelines or 5 years 
beyond our original endpoint (i.e., February 28, 2025), 
whichever occurs first. (Added the words in red) 
 
 
 
 
 
 

 
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The REDUCED Trial: REDucing the Utilization of CEsarean sections for Dystocia  
 
Primary Investigators: Dr Stephen Wood, Dr Amy Metcalfe 
 
 Summary 
 
This project is a clustered randomized controlled trial of a knowledge translation intervention of new 
guidelines for the diagnosis of poor progress in labor. The intent is to reduce the rate of cesarean 
section (CS) in first time mothers without increasing maternal or neonatal morbidity. 
 
Background: Cesarean section (CS) rates are increasing dramatically in Canada and rest of the 
western world. Preventing CS in first time mothers is the most effective way to eventually reduce the 
overall CS rate. The most common reason for CS in labor is dystocia or poor progress in labor. Poor 
progress in labor has been diagnosed for the last 60 years when the rate of cervical dilation deviates 
from the ideal rate described by the "Friedman's curve”. Recent studies in contemporary populations 
have suggested that labor in many women does not progress as fast as expected by this curve, and 
yet can still result in natural delivery. One of the key findings is that it appears that the active phase 
of labor may be delayed in many subjects until 6 cm of dilation is achieved. This is a significantly 
delayed onset to the active phase of labor compared to what physicians currently expect. These recent 
studies have formed the basis of new American clinical practice guidelines for monitoring the progress 
of labor and for diagnosing poor progress of labor (similar updated labor guidelines have not been 
adopted in other countries, including Canada). It is hoped that uptake of these new guidelines will 
substantially reduce the rate of CS in labor. Unfortunately, there is evidence that guidelines alone are 
unlikely to bring about practice change. However, tailored implementation strategies targeting 
relevant physician and nursing barriers and leveraging existing facilitators can be highly effective in 
increasing the uptake and use of new guidelines into practice. 
 
Primary Study Question: Does the implementation of an evidence-based, theory-driven knowledge 
translation strategy to apply new labor progress guidelines, result in a reduction in the risk of 
cesarean section in labor for first time mothers, at term (≥37 weeks), with a vertex presenting 
singleton fetus? 
 
Study Design: Clustered randomized controlled trial (RCT) of Alberta hospitals. 
 
Methods: This is a clustered-RCT using a cross forward design. Based on preliminary analysis of 
Alberta data we have a sufficient number of participating centres to detect a 25% reduction in the risk 
of CS. The intervention will be designed as an evidence-based, theory-driven program to bring about 
provider-level behavior change. Physician and nurse barriers and facilitators will be explored using a 
theory-structured survey. Findings will be mapped to the Capability-Opportunity-Motivation-Behavior 
Framework (COM-B) and Behavior Change Wheel generating candidate intervention functions. These 
will guide the literature based identification of appropriate candidate interventions. Candidate 
strategies will then be assessed using APRAISE (Affordability, Practicability, Effectiveness/Cost 
Effectiveness, Acceptability, Safety and Equity) and then finalized for physicians and nurses, 
respectively. We will use a labor culture survey to assess differences in unit culture between intervention 
sites and to see if those differences may explain any variation in uptake of the recent guidelines.  
 
Study Team: The study team includes experts in clinical trials, knowledge translation, intrapartum 
care, nursing education, neonatology, and health economics. It also includes representatives from two 
key end user groups, the Alberta Perinatal Health Program and the Alberta Health Services Maternal, 
Neonatal, Child and Youth Strategic Clinical Network who are providing substantial in kind support. 
 
 

 
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Background 
New American clinical practice guidelines for monitoring the progress of labor1,2 have been developed 
based on recent studies in contemporary populations3,4. If integrated into routine clinical practice, they 
may reduce the number of women diagnosed with dystocia (poor progress of labor) and therefore 
reduce the rate of cesarean section. There is strong evidence that guidelines alone are unlikely to 
bring about practice change and require a formal implementation strategy5, tailored to address 
provider barriers, facilitators and context to engineer sustained evidence use. The ultimate goal of the 
REDUCED Trial is to reduce the number of cesarean sections performed in first time mothers. To 
achieve this goal, we will use an evidence and theory driven intervention to optimize guideline use by 
labor and delivery providers in a multi-center cluster randomized controlled trial. We will assess the 
effectiveness, quality and context of the guideline use and the impact on cesarean section rates, while 
rigorously monitoring for potential harms using high fidelity data. While reducing the CS rate is a 
highly desirable patient, provider and systems-level outcome, achieving reductions in the CS rate has 
proven challenging6. This project is creative and likely to succeed in reducing cesarean section rates as 
it is based on translating a relatively simple guideline to intrapartum care providers, using 
audit/feedback methods to monitor individual and site level uptake of guidelines and proactively 
addressing barriers to implementation. We are confident that this novel approach carried out by our 
experienced and well qualified team can reduce CS rates in Alberta while providing a template for 
similar initiatives across Canada. 
 
Cesarean section (CS) rates have increased steadily in Canada and the Western world for the past 60 
years. Approximately 28% of Canadian women deliver by CS. The rate of repeat CS dropped in the 
1980's due an increase in vaginal birth after cesarean section (VBAC). However, this trend is reversing 
as women increasingly opt for a planned elective repeat CS7. This underscores the importance of 
preventing the first CS in order to lower the overall rate. The most common cause of the first CS is 
dystocia or poor progress in labor8. The standard method for diagnosing dystocia is to compare the 
patient's rate of cervical dilation in labor with the expected rate on the Friedman curve. However, 
Friedman's data came from observing only 100 primiparous women in labor only one of whom had a 
CS9. The usefulness of the Friedman curve was never confirmed with clinical trials, but it was rapidly 
and widely adopted. In most labor and delivery units, a patient’s cervical dilation is displayed on a 
partogram which includes clear indicators of poor progress and at what point "action", augmentation 
or CS, should be considered. Recently, labor progress was examined in a contemporary population in a 
large NIH funded multi-centre study. The Consortium for Safe Labor group described the rate of 
cervical dilation in 62,415 women who had vaginal deliveries and did not experience any maternal or 
neonatal complication4. This data suggests that in many women, spontaneous vaginal delivery occurs 
despite much slower rates of cervical dilation than those expected by the Friedman curve. A key 
finding is that the active phase of labor may be delayed until after 6cm of dilation is achieved. 
This is clinically meaningful as the expectation of current intrapartum care providers is that the active 
phase begins at 3-4cm. It is recommended that CS for dystocia not be performed in latent labor as 
poor progress in this phase is difficult to judge. However, based on the Consortium for Safe Labor 
data, many women are not in the active phase until 6cm dilation. Therefore, many women are being 
incorrectly diagnosed with dystocia in what is still their latent phase and having an unnecessary CS. 
The Consortium for Safe Labor study and similar data from a large sample of women undergoing 
induction of labor have been strongly endorsed by US experts and have formed the basis of new 
American clinical practice guidelines1,2. The new guidelines for the diagnosis of dystocia clearly offer 
the opportunity to reduce CS rates. However, calls for immediate widespread adoption without testing 
should be tempered by the fact that the impact of implementing these guidelines on maternal and 
neonatal outcomes is largely unknown. An unavoidable effect of implementing these guidelines is that 
fetuses will be exposed to more time in labor and therefore potentially increased risk. It is important 
to note that the Consortium for Safe Labor data were based only on women who eventually delivered 
vaginally without any maternal or neonatal complication. Therefore, it is imperative that the effect 
of these guidelines on CS rates, other maternal outcomes and neonatal outcomes be 
assessed in the most rigorous study design possible, a randomized controlled trial. 
Furthermore, if successful in reducing the CS rate, the REDUCED trial will be a substantial catalyst for 
the widespread adoption of this new approach to labor management. 
 
 
 

 
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Study Design: Cluster randomized controlled trial of a knowledge translation intervention of new 
guidelines for the diagnosis of poor progress in labor. The intervention will be randomized to centres 
(the clusters) in Alberta that provide intrapartum care, have facilities to perform cesarean section and 
deliver at least 70 primiparous women annually, with stratification based on facility type and 
geographic location. Clustering by centre and not individual caregivers (nurses/physicians) is 
necessary to prevent leakage or crossover of the intervention to controls. As all participating centres 
will eventually receive the intervention, the biostatistician will generate a randomization into two 
"waves". The intervention will be introduced sequentially by strata (Calgary, Edmonton, regional 
centres, rural centres) to the first "wave" hospitals in multi-week run-in periods after which those 
strata will be revisited for roll-out to the second "wave" hospitals. 
 
Primary Study question: 
Does an evidence-based, theory-driven Knowledge Translation intervention aimed at increasing the 
use of new clinical practice guidelines on labor progress change the rate of cesarean section (CS) in 
labor for first time mothers without increasing maternal or neonatal morbidity? 
 
Primary Outcome: Cesarean section in labor for primiparous women at term (≥37 weeks) with a 
singleton vertex presenting fetus. 
 
Secondary outcomes: Adverse neonatal and maternal outcomes including: 
 
Neonatal: 
a) Perinatal death; 
b) Neonatal Asphyxia: intrapartum stillbirth or neonatal death from asphyxia (Perinatal Society of 
Australia and New Zealand coding)10 or Neonatal Intensive Care Unit admission and at least two of: a. 
Apgar score of ≤5 at 10 minutes; b. Mechanical ventilation or chest compressions for resuscitation 
within 10 minutes; c. Cord pH < 7.00 (venous or arterial), or arterial base excess ≥ 12 at birth; 
c) moderate or severe asphyxia or meets criteria for therapeutic cooling; and 
d) sepsis or suspected sepsis. 
 
Maternal: 
a) post partum hemorrhage; 
b) blood transfusion; 
c) postpartum uterine artery/pelvic artery embolization; 
d) postpartum hysterectomy; and  
e) postpartum maternal intensive care unit (ICU) admission. 
 
Other secondary outcomes: overall CS rate in primiparous women, overall cesarean section rate, 
rate of successful trial of labor, induction rate, augmentation of labor rate, duration of labor, and 
cervical dilation prior to cesarean section. 
 
Implementation outcomes: Implementation quality (80% provider education completion pre-trial), 
site responsiveness (attendance and website tool access rates, attendance at feedback sessions by 
profession, frequency of coaching access), guideline adherence (adherence rate by site), and 
adaptation (implementation toolkit element use by site). Qualitative process and summative outcomes 
will capture how and why implementation was executed, by site, explore intrapartum and site leader 
perceptions of implementation, gather feedback on the implementation toolkit elements and utility. 
 
Randomization. 
A computer generated random allocation sequence will be created by the study statistician. 
Randomization will be stratified by type of site: urban or community. 
 
Evidence-Based, Theory-Driven Intervention Design 
The intervention itself is comprised of two parts: the clinical practice guidelines and the 
implementation strategy11 which was designed using an integrated KT strategy12 involving 

 
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collaborative efforts of the research team, intrapartum providers and leaders . The evidence base of 
the intervention is the data from the Consortium for Safe Labor study4 and Harper et al3. The findings 
were operationalized in the American College of Obstetricians and Gynecologists (ACOG)/Society for 
Maternal Fetal Medicine (SMFM) guidelines1,2. The 2012 guidelines2 provide definitions for arrest 
disorders in labor: 
1. Failed induction of labor: Failure to generate regular (e.g. every 3 minutes) contractions and 
cervical change after at least 24 hours of oxytocin administration, with artificial membrane rupture if 
feasible. 
2. First stage arrest: >=6cm dilation with membrane rupture and no cervical change for >=4 hours of 
adequate contractions or >=6 hours if contractions are inadequate. 
3. Second stage arrest: No progress (descent or rotation) for >=4 hours in nulliparous women with an 
epidural or >=3 hours in nulliparous women without an epidural. 
 
The 2014 ACOG/SMFM guidelines1 provided additional guidance for the diagnosis of arrest disorders in 
labor for nulliparous women, which was also shared with the intervention sites: 
 
First stage arrest 
• 
A prolonged latent phase (e.g., >20 h in nulliparous women) should not be indication for 
cesarean delivery. 
• 
Slow but progressive labor in first stage of labor should not be indication for cesarean delivery. 
 
 
Second stage arrest 
• 
A specific absolute maximum length of time spent in second stage of labor beyond which all 
women should undergo operative delivery has not been identified. 
• 
Before diagnosing arrest of labor in second stage, if maternal and fetal conditions permit, 
allow at least 3 h of pushing in nulliparous women. Longer durations may be appropriate on 
individualized basis (e.g., with use of epidural analgesia or with fetal malposition) as long as 
progress is being documented.  
 
Pre-Implementation Phase: 
Implementation will be guided by the Knowledge to Action Framework13 intervening at the level of 
care providers and the site. Pre-trial work is currently underway to assess guideline adaptability and 
implementability (ADAPTE II and GLIA 2.0 tools) by recruiting of a small cadre of providers. Site-
based audits will establish the nature and magnitude of the practice gap, increase understanding of 
current state and enable early engagement at the site/provider level. Current CS rates and frequency 
of CS in labor at ≤6cm of dilation data for the study centres show that since the publication of the 
Consortium for Safe Labor data in 2012 there has been no observable changes in CS rates and the 
frequency of CS at ≤6cm in Alberta. Therefore, we think it is unlikely that this data or the new 
guidelines are influencing practice and a significant practice gap remains. Two theory-driven steps14-16 
will be used to elicit barriers/facilitators and change readiness using focus groups and online surveys 
in care providers and site leaders, respectively17 A theoretical framework of behavior change domains 
will structure focus groups and survey questions14. Findings from these assessments will be mapped to 
behavior domains that are linked to an intervention design framework (Capability-Opportunity-
Motivation-Behaviour)16. Relating domains to interventions in this way will generate a set of candidate 
interventions on the Behaviour Change Wheel that can be assessed for goodness of fit for the trial 
context, feasibility, risks and cost18. Context assessment using the Consolidated Framework for 
Implementation Research19 will be used to systematically assess the individual, intervention, 
organizational and contextual-level facets of implementation20. A reliable readiness assessment tool 
will be used to understand current change readiness prior to trial kick off21,22. This process will allow 
us to develop interventions that will act on provider and site-based organizational barriers and 
facilitators, readiness and contextual factors, supplemented with access to KT/Implementation 
coaches, and an asynchronous web-based implementation toolkit. 
 
Implementation Phase: 
Interactive guideline dissemination will occur at provider-led kick off meetings, in partnership with 
administrative and clinical leaders. Meetings will be held with physicians and nurses to optimize 
engagement and interactivity. Several obstetrical medical and nursing volunteers have already 

 
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self-identified as potential clinical champions for the proposed trial. Based on our interactions with 
intervention site providers and leaders, we believe there is currently low general awareness of new 
guidelines, moderate readiness for change, and moderate-high tension for change. Key messages 
such as “avoid CS before 6cm for dystocia” etc. will be used to capture the essence of the guidelines 
for ease of use. Other specific strategies may include a large visual labor progress graph with a curve 
based on the Consortium for Safe Labor data displayed in all labor and delivery rooms. Educational 
supports will be developed to support and enhance in-person learning. Personalized login information 
will be provided to all physicians and nurses starting at the implementation kick-off meeting. 
Implementation will be facilitated by trained KT Advisors who will support site champions. . 
Implementation quality will be estimated by ensuring 80% of site providers have attended/completed 
the education units prior to trial commencement, and by ongoing KT Advisor assessment reports of 
intervention adherence, adaptation, and site responsiveness23. 
 
Post-Implementation Phase: 
Site-based audit feedback will be provided every 3-6 months to monitor uptake, and to improve post-
trial sustainability. Audit-feedback forms will be modeled on pre-existing Alberta Health Services 
dashboards that are familiar to providers. Qualitative interviews will be undertaken as part of a 
process evaluation to understand how and why guidelines and elements of the implementation toolkit 
are (or are not) being used, assess tool utility, sustainability and to explore provider/site leader 
perspectives on implementation. Factors have been designed into the implementation process to 
hedge ongoing sustainability of both the intervention and the outcomes24-26. Audit-feedback and 
clinical championship will transition as a standing item that can be revisited using pre-existing 
organizational quality infrastructure. The web portal and educational resources will be transitioned to 
the APHP. A strong pre-existing data sharing partnership with APHP will facilitate ongoing site audit 
data infrastructure. As the trial nears completion, the nature and strength of findings (outcomes and 
cost data) will be used to advocate for additional operationally-funded implementation resources to 
facilitate scale and spread at remaining sites. 
 
Sample Size/Feasibility 
Our sample size calculation is based on the assumption that a 25% relative risk reduction can be 
achieved with the intervention, i.e. a drop from 32% to 24%. Based on APHP data from 2009 to 2014, 
we have estimated the intra-cluster correlation (after adjustment for prior 5 year rate) as .002, but to 
be conservative we have assumed an ICC of .01 (well above the upper 95% confidence limit). Using 
the conventional adjustment for clusters, yields a requirement for 26 centres to provide at least 80% 
power at the usual (two-sided) 5% significance level. Simulations based on the observed 2014 
instances of primipara birth in the 26 participating hospitals show that we have power exceeding 80% 
to detect even a 10% relative risk reduction. 
 
Data Collection 
The Alberta Perinatal Health Program (APHP) collects perinatal data from the provincial delivery record 
for all hospital births in Alberta. Data from the delivery records is validated through detailed computer 
programming that double checks all variables. All the stillbirths or neonatal deaths are captured by 
APHP. 
 
APHP data is validated with Alberta Vital Statistics data for all deaths. Data is available for a number of 
variables ie: maternal demographics, type of labor, duration of labor, route of delivery, cervical 
dilation prior to CS, Apgars, neonatal resuscitation, cord blood gasses, post partum hemorrhage, 
maternal transfusion, and neonatal admission to NICU. Information is available for individual sites and 
practitioners. To assess neonatal outcomes such as asphyxia, data will be obtained from the 
Edmonton and Calgary site data of the Canadian Neonatal Network (CNN). Neonatal outcomes will 
include: intrapartum stillbirth, neonatal death, 5 minute Apgar score<7, cord pH<7.0 with base excess 
<12 mmol/l, moderate or severe asphyxia (Sarnat criteria) and therapeutic cooling. The evaluation of 
the neonatal outcomes will in collaboration with an emerging surveillance program which is monitoring 
the rate of neonatal asphyxia in Alberta. The data abstractors for the APHP and CNN will not be 
involved in the trial and will be unaware of site allocation. The data will be provided as in-kind support 
by the APHP. Given that data on at least 22,000 subjects will be provided this is an in-kind support 
equivalent to approximately 4 million dollars.  

 
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We will review the obstetrical charts of stillbirth cases from Jan 2018 to Feb 2020 to determine if the 
stillbirth occurred during the antenatal or intrapartum period. Chart review of stillbirth cases prior to 
Jan 2018 will be completed by APHP as part of their data validation process. 
 
We will use a previously validated labor culture survey to assess differences in unit culture between 
sites and to see if these differences may explain the variable uptake of the guidelines. The labor 
culture survey has six subscales that include the following: best practices to reduce cesarean delivery, 
cesarean safety, fear of vaginal birth, maternal agency, physician oversight and unit microculture.27 
The survey will also include questions related to participant and unit engagement with the REDUCED 
guidelines. 
 
The labor culture survey will be an online survey, which will be emailed to physicians and nursing staff 
at intervention sites in fall 2019. The survey will be administered by Research Electronic Data Capture 
(REDCap), which is a secure, browser-based application designed to support electronic data capture. 
The Clinical Research Unit (CRU) in the Faculty of Medicine at the University of Calgary is the REDCap 
host.  
 
[April 27, 2020 update: Due to possible effects of the COVID-19 pandemic on the trial, an urgent 
steering committee meeting was convened on April 24, 2020. The decision was made to terminate the 
study as of February 29, 2020 (i.e., prior to the World Health Organization [WHO] declaring COVID-19 
a global pandemic on March 11, 2020), instead of Phase I ending on November 30, 2019 and Phase 2 
ending on November 30, 2021. This decision was made prior to the study team receiving the final data 
for the trial. The official statement of the steering committee regarding the end of the REDUCED Trial 
due to the pandemic can be found in Appendix 1. The dates in this version of the protocol reflect the 
new end date of the trial of February 29, 2020, and changes are bolded]. 
 
Data collection will include retrospective (baseline) data for the two years prior to the roll out of the 
intervention (2015 and 2016) and will continue until 27 months after the completion of 
implementation for all sites (February 29, 2020). Intervention and post-intervention periods will be 
defined for intervention sites according to their dates of initiation and completion of implementation.  
 
A random sample of obstetrical charts will be reviewed from the 13 intervention sites during the 
27 month period from Dec 1, 2017 to February 29, 2020 to determine the percentage of cesarean 
sections for dystocia that were done following the ACOG/SMFM guidelines. A minimum of 50 charts 
per site will be reviewed. If there are fewer than 50 cesarean sections for dystocia at a given site, 
then all of the dystocia cases during the two-year period will be reviewed.  
 
Statistical Analysis 
The analysis will be conducted independently by the study statistician (RB). The primary outcome will 
not be changed during analysis. The trial with an explicit statement of the primary outcome will be 
registered at clinicaltrials.gov. 
 
The primary analysis will include individual level data from all sites from the baseline period (2015 to 
2016) and follow-up thereafter in both arms. The intervention period will defined separately for each 
intervention site according to the date of completion of implementation of the program (which varied 
for the 13 intervention sites from January 31, 2017 to November 30, 2017).  Data from the 
implementation phase (nominally one to two months) will be excluded as a wash-out period. The 
intervention period ends February 29, 2020 (27 months after completion of site initiation at all 
intervention sites). 
 
CS rates will be assessed using repeated measures mixed effects logistic regression applied to 
individual births.  We will apply a constrained baseline approach to adjust for pre-intervention data28.  
Explanatory variables (fixed effects) in the model will include time period (in 6 month intervals), and 
indicators for intervention and post-intervention phases in the intervention sites. The post-intervention 

 
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parameter will represent the primary measure of efficacy. Corresponding site-specific random effects 
will be included for all fixed effects29.   
 
Having fewer than 40 sites, a small sample correction will be applied to the standard error for group 
differences underlying significance tests and confidence interval construction30. 
 
If the study has null results it will be important to try and determine if this were due to the 
ineffectiveness of the guidelines or poor adherence. Therefore, we also plan to assess indicators of 
guideline uptake such as changes in: duration of labor, time from admission until CS in non-
progressing labors and rates of CS for dystocia <6cm.   
 
Descriptive statistics will be used to characterize the labor culture at each site. We will use multiple 
linear regression to assess the relation between post-intervention percent change in cesarean section 
rate and site-level sub-scale means in the labor culture survey. In addition, we will examine the 
association between change in cesarean section rate and adherence to the guidelines for each site by 
simple linear regression. 
 
February 2023 UPDATE: REVISED PHASE 2 
 
We will conduct a follow-up analysis of the data (revised Phase 2), which will include an analysis of the 
post-intervention period extending to the date that the Society of Obstetricians and Gynaecologists of 
Canada (SOGC) changes their labour management guidelines to reflect the ACOG/SMFM guidelines or 
5 years beyond our original endpoint (i.e., February 28, 2025), whichever occurs first.  
 
Economic analysis 
An economic evaluation will be conducted alongside the trial. The time horizon for the analysis will be 
to hospital discharge for both mother and baby. Costing will include the cost of the knowledge 
translation intervention implementation of the intervention including staff hours for participants and 
trainers, production of print materials, audit and feedback and also health care utilization during labor 
and delivery (CS rates, labor time, length of stay for mom and baby). The resource utilization, and 
costs, for costing the KT intervention will be collected by study team alongside the trial. Data on 
health care resource utilization, and the associated costs, will be collected as part of the trial from 
APHP and the Discharge Abstract Database of the Canadian Institute of Health Information. Outcomes 
will include maternal and neonatal morbidity/mortality, and patient experience also collected from 
administrative data. 
 
Sources of Bias 
We anticipate that some reviewers would prefer a broader intervention aimed at multiple risk factors 
for CS. However, existing clinical trial data does not suggest that reducing exposure to commonly 
touted risk factors for CS such as labor induction, epidural anesthesia or continuous fetal heart rate 
monitoring are effective at preventing CS6,31,32. Furthermore, a recent multi-centre clustered RCT in 
Quebec evaluated a comprehensive multi-modal program and were only able to reduce CS rates by 
1.8%33. Other complex strategies such as the active management of labor have also been ineffective 
at clearly reducing CS rates 34,35. We also anticipate that the simplicity of our intervention will improve 
adoption as increased complexity of an innovation has been shown to inhibit its adoption32. The main 
source of bias in our study is contamination or crossover of the intervention to control sites which 
could make it difficult to demonstrate a change in the primary outcome. While possible we think this is 
unlikely as the vast majority of physicians providing maternity care in Alberta work at only one 
hospital and we do not anticipate large numbers will change hospitals over the course of the trial. 
None the less crossover is a real concern. However, our data will allow us to at least monitor if 
unexpected changes occur at control sites. Another possible source of bias is that practitioners will be 
insufficiently incentivized to change. Judging from the strong support we have seen so far from 
provider representatives we think this is unlikely. Furthermore, we will provide specific and meaningful 
incentives for providers such as reimbursement for time and continuing education credits. 
 
Data Safety Monitoring Committee (DMSC) 

 
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Data will be provided by APHP. The members will be Tracee Pratt (Executive Director, Royal Alexandra 
Hospital), Dr. Reg Sauve (University of Calgary) and Dr. Bill Fraser (Director of the Research Centre of 
the CHUS hospital). These individuals have extensive knowledge of the subject and experience in 
clinical trials. The safety analysis will be performed for data up to June 30, 2018 as this is the midway 
point to the primary analysis.  
 
Timeline 
This project will be completed within 3 years. Transitioning control sites to intervention sites will begin 
following the COVID-19 pandemic, if Phase 1 of the trial is considered successful. 
 
 
 
References 
1. 
Caughey AB, Cahill AG, Guise JM, Rouse DJ. Safe prevention of the primary cesarean delivery. 
Am J Obstet Gynecol 2014; 210(3): 179-93. 
2. 
Spong CY, Berghella V, Wenstrom KD, Mercer BM, Saade GR. Preventing the first cesarean 
delivery: summary of a joint Eunice Kennedy Shriver National Institute of Child Health and Human 
Development, Society for Maternal-Fetal Medicine, and American College of Obstetricians and 
Gynecologists Workshop. Obstetrics & Gynecology 2012; 120(5): 1181-93. 
3. 
Harper LM, Caughey AB, Odibo AO, Roehl KA, Zhao Q, Cahill AG. Normal progress of induced 
labor. Obstetrics & Gynecology 2012; 119(6): 1113-8. 
4. 
Zhang J, Landy HJ, Branch DW, et al. Contemporary patterns of spontaneous labor with normal 
neonatal outcomes. Obstetrics & Gynecology 2010; 116(6): 1281-7. 
5. 
Davis DA, Taylor-Vaisey A. Translating guidelines into practice. A systematic review of theoretic 
concepts, practical experience and research evidence in the adoption of clinical practice guidelines. 
CMAJ Canadian Medical Association Journal 1997; 157(4): 408-16. 
6. 
Hartmann KE, Andrews JC, Jerome RN, et al. Strategies to Reduce Cesarean Birth in Low Risk 
Women. AHRQ Publications 2012; 12(13): EHC128-EF. 
7. 
Uddin SF, Simon AE. Rates and success rates of trial of labor after cesarean delivery in the 
United States, 1990-2009. Maternal & Child Health Journal 2013; 17(7): 1309-14. 
8. 
Anderson GM, Lomas J. Recent trends in cesarean section rates in Ontario. CMAJ 1989; 141: 
1049-52. 
9. 
Friedman EA. The Graphical Analysis of Labor. Am J Obstet Gynecol 1954; 68(6): 1568-75. 
10. 
Chan A, King JF, Flenady V, Haslam RH, Tudehope DI. Classification of perinatal deaths: 
development of the Australian and New Zealand classifications. Journal of paediatrics and child health 
2004; 40(7): 340-7. 
11. 
Moore J, Khan S, Straus S. Designing an ETP" (Evidence-Based, Theory Driven Program)-
Practicing Knowledge Translation. St Michaels Hospital  Toronto Canada; 2015. 
12. 
Graham ID, Tetro JM, Pearson A. Turning Knowledge into Action: Practical Guidelines on How to 
do Integrated Knowledge Translation Research. Philadelphia PA: Lippincott Wiliams&Wilkins; 2014. 
13. 
Graham I, Logan J, Harrison MB, et al. Lost in Knowledge Translation: Time for a Map? The 
Journal of Continuing Education in the Health Professions 2006; 26: 13-24. 
14. 
Michie S, Johnston M, Francis J, Hardeman W, Eccles M. From Theory to Intervention: Mapping 
Theoretically Derived Behavioural Determinants to Behaviour Change Techniques. Applied Psychology: 
An international review 2008; 57(4): 660-80. 
15. 
Michie S, Johnston M, Abraham C, et al. Making psychological theory useful for implementing 
evidence based practice: a consensus approach. Quality & Safety in Health Care 2005; 14(1): 26-33. 

 
Version 9 (Nov 8, 2023) 
 
12 
 
16. 
Michie S, Abraham C, Eccles MP, Francis JJ, Hardeman W, Johnston M. Strengthening evaluation 
and implementation by specifying components of behaviour change interventions: a study protocol. 
Implementation Science 2011; 6: 10. 
17. 
Chaillet N, Dumont A. Evidence-based strategies for reducing cesarean section rates: A meta-
analysis. Birth 2007; 34(1): Mar. 
18. 
Michie S, Atkins L, West R. The Behaviour Change Wheel: A Guide to Designing Interventions. 1st 
ed. Great Britain: Silverback publishing; 2014. 
19. 
Damschroder LJ, Aron DC, Keith RE, Kirsh SR, Alexander JA, Lowery JC. Fostering implementation 
of health services research findings into practice: a consolidated framework for advancing 
implementation science. Implementation Science 2009; 4: 50. 
20. 
Rycroft-Malone J, Bucknell T. Models and  Frameworks for Implementing Evidence Based 
Practice: Linking evidence to action. 1st ed: Wiley-Blackwell; 2010. 
21. 
Program KT. Ready! Set! Change! Decison support tool. Toronto: St Michael's Hospital; 2014. 
22. 
Khan S, Timmings C, Moore JE, et al. The development of an online decision support tool for 
organizational readiness for change. Implementation Science 2014; 9: 56. 
23. 
Durlak JA, DuPre EP. Implementation matters: a review of research on the influence of 
implementation on program outcomes and the factors affecting implementation. American Journal of 
Community Psychology 2008; 41(3-4): 327-50. 
24. 
Doyle C, Howe C, Woodcock T, et al. Making change last: applying the NHS institute for 
innovation and improvement sustainability model to healthcare improvement. Implementation Science 
2013; 8: 127. 
25. 
Fleiszer AR, Semenic SE, Ritchie JA, Richer MC, Denis JL. The sustainability of healthcare 
innovations: a concept analysis. Journal of Advanced Nursing 2015; 71(7): 1484-98. 
26. 
Moore J, Khan S. "Sustainability, Spread and Scale Up" Practicing Knowledge Translation. 
Toronto: St Michaels' Hospital; 2016. 
27. 
White VanGompel E, Perez S, Wang C, Datta A, Cape V, Main E. Measuring labor and delivery 
unit culture and clinicians' attitudes toward birth: Revision and validation of the Labor Culture Survey. 
Birth 2018. 
28. 
Klar N, Darlington G. Methods for modelling change in cluster randomization trials. Statistics in 
Medicine 2004; 23(15): 2341-57. 
29. 
Leyrat C, Morgan KE, Leurent B, Kahan BC. Cluster randomized trials with a small number of 
clusters: which analyses should be used? International Journal of Epidemiology 2018; 47(1): 321-31. 
30.  
Hooper R,Forbes A, Hemming K, Takeda A,Beresford L. Analysis of cluster randomised trials 
with an assessment of outcome at baseline, BMJ 2018;360-1121, 
doi: 10.1136/bmj.k1121  
31. 
Halpern SH, Leighton BL, Ohlsson A, Barrett JF, Rice A. Effect of epidural vs parenteral opioid 
analgesia on the progress of labor: a meta-analysis. JAMA 1998; 280(24): 2105-10. 
32. 
Wood S, Cooper S, Ross S. Does induction of labour increase the risk of caesarean section? A 
systematic review and meta-analysis of trials in women with intact membranes. BJOG: an International 
Journal of Obstetrics & Gynaecology 2014; 121(6): 674-85. 
33. 
Chaillet N, Dumont A, Abrahamowicz M, et al. A cluster-randomized trial to reduce cesarean 
delivery rates in Quebec. N Engl J Med 2015; 372(18): 1710-21. 
34. 
Brown HC, Paranjothy S, Dowswell T, Thomas J. Package of care for active management in 
labour for reducing caesarean section rates in low-risk women. Cochrane Database of Systematic 
Reviews 2013; 9: 00075320-100000000-03894. 

 
Version 9 (Nov 8, 2023) 
 
13 
 
35. 
Bugg GJ, Siddiqui F, Thornton JG. Oxytocin versus no treatment or delayed treatment for slow 
progress in the first stage of spontaneous labour. Cochrane Database of Systematic Reviews 2013; 6: 
00075320-100000000-05791. 
36.         Calgary Zone Women's Health. Patient Screening and Fever Management During COVID-19 
2020. 
APPENDIX 1 
 
REDUCED TRIAL STEERING COMMITTEE’S STATEMENT REGARDING THE END OF THE REDUCED TRIAL 
DUE TO COVID-19 PANDEMIC 
(April 24, 2020) 
Given the impact of the COVID-19 pandemic, data collection for the REDUCED Trial will be considered 
ended on February 29, 2020 (i.e., prior to the World Health Organization [WHO] declaring COVID-19 a 
global pandemic on March 11, 2020), instead of Phase 1 ending on November 30, 2019 and Phase 2 
ending on November 30, 2021. 
 
Labour management post-pandemic has materially changed our ability to move forward with our 
research for a number of reasons. Currently, the physicians’ and nursing staff’s focus is on COVID-
related issues, and we anticipate that caregivers and their patients will be less patient during labour. 
Furthermore, there are documents, such as the Calgary Zone Women’s Health’s Patient Screening and 
Fever Management During COVID-1936, which includes guidance that is not congruent with the 
REDUCED guidelines (e.g., avoiding delayed pushing). Given the current environment, we do not think 
that this is an appropriate time to engage physicians and nurses about the trial guidelines, or physicians 
in audit feedback related to the trial. Furthermore, two of our sites (one intervention site and one 
control site) have temporarily closed their labour and delivery units during this time.