C O M M E N T A R Y Open Access
Community-led trials: Intervention co-design
in a cluster randomised controlled trial
From The Camino Verde Trial colloquium
Acapulco, Mexico. 17-21 June 2013
In conventional randomised controlled trials (RCTs), researchers design the interventions. In the Camino Verde trial,
each intervention community designed its own programmes to prevent dengue. Instead of fixed actions or menus
of activities to choose from, the trial randomised clusters to a participatory research protocol that began with
sharing and discussing evidence from a local survey, going on to local authorship of the action plan for vector
Adding equitable stakeholder engagement to RCT infrastructure anchors the research culturally, making it more
meaningful to stakeholders. Replicability in other conditions is straightforward, since all intervention clusters used
the same engagement protocol to discuss and to mobilize for dengue prevention. The ethical codes associated
with RCTs play out differently in community-led pragmatic trials, where communities essentially choose what they
want to do. Several discussion groups in each intervention community produced multiple plans for prevention,
recognising different time lines. Some chose fast turnarounds, like elimination of breeding sites, and some chose
longer term actions like garbage disposal and improving water supplies.
A big part of the skill set for community-led trials is being able to stand back and simply support communities in
what they want to do and how they want to do it, something that does not come naturally to many vector control
programs or to RCT researchers. Unexpected negative outcomes can come from the turbulence implicit in
participatory research. One example was the gender dynamic in the Mexican arm of the Camino Verde trial. Strong
involvement of women in dengue control activities seems to have discouraged men in settings where activity in
public spaces or outside of the home would ordinarily be considered a “male competence”.
Community-led trials address the tension between one-size-fits-all programme interventions and local needs.
Whatever the conventional wisdom about how prevention works at a system level, programmes have to be
perceived as locally relevant and they must engage stakeholders who make them work. Locally, each participating
community has to know the intervention is relevant to them; they have to want to do it. That happens much more
easily if they design the programme themselves.
The British Medical Journal published the multi-centred
Camino Verde cluster randomised controlled trial  as
the first report of a community mobilisation intervention
leading to serological evidence of reduced dengue virus
infection. Beyond dengue prevention, publication of the
Camino Verde trial in the BMJ showed that community-
led trials can be reported in high quality journals.
In conventional randomised controlled trials (RCTs), re-
searchers design the interventions. In the RCT world of
researcher hypotheses, concepts like fidelity and reprodu-
cibility have been interpreted to mean that all participants
–all clusters in a cluster RCT –must receive verifiably
the same intervention. In the Camino Verde trial, each
intervention community designed its own set of actions to
prevent dengue. Instead of a fixed prevention programme
or menu of activities to choose from, the trial randomised
Centro de Investigación de Enfermedades Tropicales (CIET), Universidad
Autónoma de Guerrero, Acapulco, Guerrero, Mexico
Department of Family Medicine, McGill University, Montreal, Canada
© The Author(s). 2017 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0
International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and
reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to
the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver
(http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
The Author(s) BMC Public Health 2017, 17(Suppl 1):397
clusters to a participatory research protocol that began
with sharing and discussing evidence, leading to local
authorship of the action plan for vector control. A similar
protocol, without the vector-specific references, might be
applicable to many health or social issues.
Evolution of RCT methods
Public health research has evolved beyond observational
studies, increasingly to includeRCTs.Theseexperiments
involve comparisons with people who do not receive the
intervention (controls), and rely on random allocation of
the intervention to generate convincing evidence of impact
or lack of impact. The consequence of randomisation is
that exposure to the intervention is independent of all
events and relationships that precede it –it converts poten-
tial confounders and other covariates into random differ-
ences. This lifts the onerous and often futile burden of
proof of observational studies, where the researcher is
obliged to exclude potential confounders as possible expla-
nations of a presumed effect [2, 3].
In the three-quarters of a century since the first pub-
lished RCT in the 1930s , we have seen major develop-
ments of trial methods in several directions. The biggest
volume of health-related RCTs is undisputedly the clinical
trials sponsored by the pharmaceutical industry , essen-
tially to comply with legal requirements about proof of ef-
ficacy. There has also been a surge of the n-of-1 clinical
management trials used in personalised medicine [6, 7]
and most recently the emergence of pragmatic trials with
implications for large scale public health policy [8–10].
Pragmatic trials refocus RCT methodology such that
randomising and comparing with a control group are the
principal contributions of the trial; there is no longer any
double blinding or placebos that were almost synonymous
with efficacy trials . The related surge in public policy
trials brought to light the advantage of clusters to reduce
contamination bias for educational and mobilisation inter-
ventions; where interventions work between people,in-
stead of trying to isolate people to avoid spill-over, it
makes sense to intervene at cluster level.
There have also been shifts in the definition of the
intervention in trials. Brown and others  defined
adaptive trials as having planned modification of charac-
teristics of the intervention based on information from
the accumulating data. Product development adaptive
trials, borrowed from business studies, now talk about
involving “consumers”in programme development at all
stages [13, 14]. Community-led trials, although with very
different origins in participatory research, benefit from
some of these technical developments in RCT methods.
Participatory research in an epidemiological framework
Participatory research is an umbrella term that includes
partnered research, community-based participatory
research, action research, participatory action research,
participatory evaluation, community and patient engage-
ment . It implies the systematic co-creation of new
knowledge in equitable partnerships with people affected
or those who will benefit from or act on it [16, 17]. Al-
though participatory research for some people implies
small scale, very local exercises, there is nothing in its
definition that excludes national and multi-national par-
ticipatory research operations .
Adding equitable stakeholder engagement to RCT in-
frastructure has several benefits : cultural anchoring
shapes the scope and direction of research, making it
more meaningful to stakeholders; recruitment of com-
munity members to management roles builds capacity;
the dialogic approach leads to creative turbulence that,
when resolved, promotes positive and sustained out-
comes; success increases confidence over time, with im-
plications for other health issues; goals are often
sustained beyond funded time frames; and systemic
changes achieved from the engagement have wider
An early example of a community-led trial, Rebuilding
from Resilience ,was a partnership of 12 Indigenous
women’s shelters across Canada. This tested the impact
and cost implications of evidence-based community-led
initiatives to decrease domestic violence. The women’s
shelter directors took the driving seat in their own re-
search. They viewed randomisation as the only fair way
to decide whose turn it was to receive the available re-
sources; each shelter director drew a number out of a
hat, indicating whether their shelter would join the first
wave or the second wave. In each community, a detailed
development and consultation process led to a baseline
study, using other gender violence questionnaires as ref-
erence. The results fuelled a series of discussions and
workshops on how to prevent gender violence. The
baseline for the second wave provided the unexposed
contrast for the follow-up study of the first wave, after 2
years of interventions.
Implementation and interpretation of community-led
Camino Verde illustrates some issues in the design, im-
plementation and interpretation of community-led trials.
Replication of the intervention
Because Camino Verde randomised a participatory re-
search protocol, the conclusion of the trial should
strictly be that participatory research –rather than spe-
cific vector control actions –added value to existing
programmes attempting to reduce dengue virus infec-
tion. There is no problem about ensuring replication
 in other conditions, since each intervention cluster
The Author(s) BMC Public Health 2017, 17(Suppl 1):397 Page 6 of 173
received the same evidence-based engagement protocol
to discuss and to mobilise for dengue prevention .
The stringent ethical codes associated with RCTs, includ-
ing informed consent , play out differently in explana-
tory trials and community-led pragmatic trials, where
communities essentially choose what they want to do .
Issues of withholding interventions in control communi-
ties  can be settled by randomising the delay among
all eligible communities, as in a stepped wedge design. Re-
sidual problems include demonstrating respect for com-
munity autonomy when the locus of research shifts from
the individual to community level .
Intervention co-design is neither easy nor automatic,
and communities do not always come up quickly with
the most effective solutions. In Camino Verde, the ap-
proach to community-led design took 3 years to develop
prior to the main trial. Once the protocol was in place,
many residents started with the idea that government
should solve their dengue problem. Between the differ-
ent discussion groups in each intervention community
that led to multiple plans for prevention, most commu-
nities developed their compound intervention recognis-
ing different time lines; they chose some fast
turnarounds, like elimination of breeding sites, and lon-
ger term actions like garbage disposal and improving
Selection bias can be reduced by concealment of centra-
lised allocation of the intervention. As in most pragmatic
trials, blinding and placebos are impossible in
community-led trials, and biases can result from service
providers and communities knowing what the interven-
tions are. In a community-led trial a Hawthorne effect
(an impact because the group receiving the intervention
know they are receiving an intervention) is likely and is
part of the intervention benefit. Practical steps to ensure
knowledge of allocation of the intervention affects the
outcome measure as little as possible can include using
biological outcomes (such as serological evidence of
dengue infection in the Camino Verde trial) rather than
responses from officials. In interventions where partici-
pants choose what they do, it is possible that their
choice of intervention is influenced by what they read
. In Camino Verde, communities chose the interven-
tion based on evidence of local vector habits and com-
munity discussions, so there was little risk of a
In any trial, a rigid and well documented protocol helps
avoid undisclosed implementation flexibility ; this is
also true for community-led trials, when the interven-
tion is to share information and co-design solutions.
What individual intervention communities opted to do
in the Camino Verde trial was up to them, but the work
of the Camino Verde trial team adhered tightly to the
protocol. Mostly this involved training of facilitators and
handing over the evidence for discussion.
In any cluster trial, a lot of analytic power is foregone
when cluster is the unit of randomisation and the unit of
intervention . The Camino Verde main analysis per
protocol was the most conservative possible for a cluster
trial: a t-test treated each cluster as a unit and the out-
come rate as continuous variables in each cluster.
Strictly following protocol, as happened in the Camino
Verde analysis, avoids p-hacking  and hypothesizing
after the results are known (HARKing) . This is es-
pecially important in community-led trials where local
initiatives can give rise to unexpected and interesting
ways of doing things. A Camino Verde example was the
reintroduction of larvivorous fish in some communities;
this generated interesting supplementary results  but
did not influence the trial’s principal analysis.
Ambiguity of indicators
Ambiguity of indicators and difficulty in defining the
measurement parameters are not avoided by randomisa-
tion and can cause problems in clinical, pragmatic and
community-led trials. With the further variability intro-
duced by different packages of solutions in each partici-
pating community, a reliable endpoint is helpful.
Camino Verde opted for a hard biological endpoint:
serological evidence of dengue virus infection.
Skills and infrastructure
Introduction of high level research methods and partici-
patory research into local programme development has
multiple advantages, including improving the
programme in question, but it requires a quantum shift
in skills and sensibilities. The key to almost any trial is
in the measurement skill. In community-led trials, add-
itional skills of promoting dialogue, often in an intercul-
tural context, are indispensable. An article by Morales-
Pérez and colleagues describes the training of Mexican
facilitators in the Camino Verde trial . A big part of
the skill set is being able to stand back and simply sup-
port communities in what they want to do and how they
want to do it, something that does not come naturally to
many vector control programs.
The Author(s) BMC Public Health 2017, 17(Suppl 1):397 Page 7 of 173
Unexpected negative outcomes
The turbulence implicit in any participatory research
process can in the short term introduce and exacerbate
local frictions. One example of this is the gender dy-
namic that seems to have resulted from the surge of
interest and involvement of women and children in the
Mexican arm of the Camino Verde trial . Analysis
indicated interruptions of the results chain between
knowledge and preventive action in men exposed to the
intervention. It seems plausible that the strong involve-
ment of women in dengue control activities had a nega-
tive effect on the men in communities where activity in
public spaces or outside of the home would ordinarily
be considered a “male competence”.
The way forward
The Camino Verde trial is an interesting precedent for
community-led RCTs in public health, addressing the
well-known tension between programme interventions
and local needs. For logistical and administrative pur-
poses, public health programmes have objectives, actions
to reach those objectives, outputs, outcomes and im-
pacts. Unfortunately, that strong sense of system does
little to make programmes locally relevant or engaging
to stakeholders who must make them work. Locally,
each participating community has to know the interven-
tion is relevant to them; they have to want to do it. That
happens much more easily if they design the programme
Public health practitioners are increasingly recognising
that stakeholder engagement and participation is crucial
for success. There is nothing new in this proposition, be-
ing a founding principle of the 1978 primary health care
concept at Alma Ata . The decentralised nature of
engagement and participation has long been held to be
contradictory to any one-size-fits-all formulation.
Community-led RCTs provide informative answers to a
few very specific questions.
Where the objective of the exercise is very clear –in
this case it was to control Aedes aegypti –and there are
several options of how to achieve this, quite what com-
munities do should not matter so much as that they do
I thank Anne Cockcroft for her input into drafts of the article.
The UBS Optimus Foundation provided funding for publication of this
NA conceived and wrote the article.
The author declares that he has no competing interests.
About this supplement
This article has been published as part of BMC Public Health Volume 17
Supplement 1, 2017: The Green Way to Aedes aegypti mosquito control:
aspects and implications of the Camino Verde trial in Mexico and Nicaragua.
The full contents of the supplement are available online at https://
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Published: 30 May 2017
1. Andersson N, Nava-Aguilera E, Arosteguí J, Morales-Perez A, Suaso-Laguna
H, Legorreta-Soberanis J, et al. Evidence based community mobilisation for
dengue prevention in Nicaragua and Mexico (Camino Verde, the green
way): cluster randomized controlled trial. BMJ. 2015;351:h3267.
2. Leeuw F, Vaessen J. Impact evaluations and development: Nonie guidance
on impact evaluation: Independent Evaluation Group, World Bank; 2010.
(Accessed 2 May 2017).
3. Moher D, Hopewell S, Schulz KF, Montori V, Gøtzsche PC, Devereaux PJ, et
al. CONSORT 2010 explanation and elaboration: updated guidelines for
reporting parallel group randomised trials. BMJ. 2010;340:c869.
4. Amberson JB Jr, McMahon BT, Pinner M. A clinical trial of sanocrysin in
pulmonary tuberculosis. Am Rev Tuberc. 1931;24:401–35.
5. Bothwell LE, Greene JA, Podolsky SH, Jones DS. Assessing the gold standard
—lessons from the history of RCTs. N Engl J Med. 2016;374:2175–81.
6. Fiore LD, Lavori PW. Integrating randomized comparative effectiveness
research with patient care. N Engl J Med. 2016;374:2152–8.
7. Guyatt GH, Keller JL, Jaeschke R, Rosenbloom D, Adachi JD, Newhouse MT.
The n-of-1 randomized controlled trial: clinical usefulness —our three-year
experience. Ann Intern Med. 1990;112:293–9.
8. Godwin M, Ruhland L, Casson I, MacDonald S, Delva D, Birtwhistle R, et al.
Pragmatic controlled clinical trials in primary care: the struggle between
external and internal validity. BMC Med Res Methodol. 2003;3:28.
9. Bamberger M, White H. Using strong evaluation designs in developing
countries: experience and challenges. J Multi Discip Eval. 2007;4(8):58–73.
10. Andersson N. Proof of impact and pipeline planning: directions and
challenges for social audit in the health sector. BMC Health Serv Res. 2011;
11. Roland M, Torgerson DJ. Understanding controlled trials: what are
pragmatic trials? BMJ. 1998;316(7127):285.
12. Brown CH, Ten Have TR, Jo B, et al. Adaptive designs for randomized trials
in public health. Annu Rev Public Health. 2009;30:1–25.
13. Sandler I, Ostrom A, Bitner M, Ayers T, Wolchik S, Daniels V. Developing
effective prevention services for the real world: a prevention service
development model. Am J Commun Psychol. 2005;35:127–42.
14. Daniels VS, Sandler I, Wolchik S. Use of quality management methods in the
transition from efficacious prevention programs to effective prevention
services Am J Community Psychol 2008;41:250-261.
15. Cargo M, Mercer SL. The value and challenges of participatory research:
strengthening its practice. Ann Rev Public Health. 2008;29:325–50.
16. Israel BA, Schulz AJ, Parker EA, Becker AB. Review of community-based
research: assessing partnership approaches to improve public health Annu
Rev Public Health 1998; 19:173-202.
17. Macaulay AC, Commanda LE, Freeman WL, Gibson N, McCabe ML, Robbins
CM, et al. Participatory research maximises community and lay involvement.
North American primary care research group. BMJ. 1999;319:774–8.
18. Andersson N. Building the community voice into planning: 25 years of
methods development in social audit. BMC Health Serv Res. 2011;11(supp2):S1.
19. Jagosh J, Macaulay AC, Pluye P, Salsberg J, Bush PL, Henderson J, et al.
Uncovering the benefits of participatory research: implications of a realist
review for health research and practice. Milbank Q. 2012;90:311–46.
20. Andersson N, Sioui G, Shea B, Harper A, McGuire P. Rebuilding from
resilience: research framework for a randomised controlled trial of
community-led interventions to prevent of domestic violence in aboriginal
communities. Pimatisiwin. 2010;8:61–88.
The Author(s) BMC Public Health 2017, 17(Suppl 1):397 Page 8 of 173
21. Makel MC, Plucker JA, Hegarty B. Replications in psychology research: how
often do they really occur? Perspect Psychol Sci. 2012;7:537–42.
22. Hernandez-Alvarez C, Arosteguí J, Suazo-Laguna H, Reyes RM, Coloma J, Harris
E, et al. Community cost-benefit discussion that launched the Camino Verde
intervention in Nicaragua. BMC Public Health. 2017;17(Suppl 1). doi:10.1186/
23. Barahona C. Randomised control trials for the impact evaluation of
development initiatives: a statistician’s point of view. ILAC working paper 13,
No13_Randomised%20Control%20Trials.pdf. (Accessed 2 May 2017).
24. Ledogar RJ, Hernández-Alvarez C, Morrison AC, Arosteguí J, Morales-Pérez A,
Nava-Aguilera E, et al. When communities are really in control: ethical issues
surrounding community mobilisation for dengue prevention in Mexico and
Nicaragua. BMC Public Health. 2017;17(Suppl 1). doi:10.1186/s12889-017-
25. Ravallion M. Should the randomistas rule? Economists Voice. 2009;6:1–5.
(Accessed 2 May 2017).
26. Buchanan DR, Miller FG, Wallerstein N. Ethical issues in community-based
participatory research: balancing rigorous research with community
participation in community intervention studies. Prog Community Health
27. Fanelli D. “positive”results increase down the hierarchy of the sciences.
PLoS One. 2010;5:e10068.
28. Simmons JP, Nelson LD, Simonsohn U. False-positive psychology:
undisclosed flexibility in data collection and analysis allows presenting
anything as significant Psychol Sci 2011;22:1359–1366.
29. Button KS. Power failure: why small sample size undermines the reliability of
neuroscience. Nat Rev Neurosci. 2013;14:365–76.
30. John LK, Loewenstein G, Prelec D. Measuring the prevalence of
questionable research practices with incentives for truth telling Psychol Sci
31. Kerr NL. HARKing: hypothesizing after the results are known. Personal Soc
Psychol Rev. 1998;2:196–217.
32. Morales-Pérez A, Nava-Aguilera E, Legorreta-Soberanis J, Cortés-Guzmán AJ,
Balanzar-Martínez A, Harris E et al. “Where we put little fish in the water
there are no mosquitoes:”A cross-sectional study on biological control of
the Aedes aegypti vector in 90 coastal communities of Guerrero, Mexico.
BMC Public Health. 2017;17(Suppl 1). doi:10.1186/s12889-017-4302-z.
33. Morales-Pérez A, Nava-Aguilera E, Legorreta-Soberanis J, Paredes-Solís S,
Balanzar-Martínez A, Serrano-de los Santos FR, et al. Which Green Way:
mobilising for Aedes aegypti control under difficult security conditions in
southern Mexico. BMC Public Health. 2017;17(Suppl 1). doi:10.1186/s12889-
34. Andersson N, Beauchamp M, Nava-Aguilera E, Paredes-Solís S, Šajna M. The
women made it work: fuzzy transitive closure of the results chain in a
dengue prevention trial in Mexico. BMC Public Health. 2017;17(Suppl 1). doi:
35. World Health Organisation. Declaration of Alma-Ata. International
Conference on Primary Health Care, Alma-Ata, USSR, 6–12 Sept 1978.
Accessed 2 May 2017.
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