This webinar explores how to effectively tackle complex public health challenges by shifting from traditional, linear approaches to embracing complex systems thinking, emphasizing the need for multi-level, long-term interventions and a rebalancing of evidence generation towards upstream, population-level actions.
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hello and welcome to this Health
Foundation webinar on complex public
health challenges and local action how
does local government to tackle
complexity I'm delighted to be here
today and it's great that so many of you
who've been able to join us my name is
Jane Landon and I'm a senior policy
fellow at the Health Foundation and I'll
be chairing the session today I'd like
now to introduce our two speakers on
this webinar on my right dr. Harry
Rutter who is clinical research research
fellow at the London School of Hygiene
and Tropical Medicine hi Harry
hi and on my left professor Jim McManus
who is the director of public health at
Hofstra County Council warm welcome Jim
thank you hello this is our first
webinar on a topic which is part of our
healthy lives work here at the Health
Foundation our healthy life strategy
aims to improve health looking beyond
the health care system by supporting
cross-sectoral action on the social
determinants of health one of the major
challenges of for Public Health is how
do we generate evidence that is useful
to decision-makers and that reflects the
multi-factor from nature of the health
issues that we face today issues such as
obesity such as poor mental health and
such as health inequalities also how do
we understand the factors which drive
these different problems as part of the
healthy life strategy we are pleased to
be working with Harry on a program of
work which aims to help overcome some of
the research challenges and to support
the use of different methodologies that
we need for population level as well as
individual level interventions we'll
hear a bit more from Harry about that in
a moment so please do send us your
questions during the presentations you
can do that by typing them into the box
on the left hand side of your screen
we'll be monitoring those questions over
the course of the presentations as they
come in and we'll start the question and
answer session once we have heard from
both of our speakers so first we're
going to hear from Harry who is going to explain
explain
now we can think about public health
challenges in terms of complex systems
to develop new approaches to both the
design and the evaluation of population
level interventions interventions that
can improve public health
thanks very much Jane so my talk today
is in just 20 minutes going to try and
start to explore some of the problems
that we face in public health that
traditional approaches have hit a bit of
a stumbling block at dealing with and
start to explore some of the ways in
which a complex systems thinking
approach might be able to help us get
over some of those challenges and then
lead into practical responses to them
that Jim is going to talk about some
more we hear a lot about evidence when
we're talking about health and rightly
so but sometimes the evidence that we
have is less helpful than it might be
and one of the metaphors I've used for
this is to come up with this idea of
something that I've called a dangerous
olive of evidence so if all of you
watching this now were to write down on
a piece of paper your top three things
that you believe would make a difference
to reducing obesity things for which we
we may not have firm evidence we may not
have a solid trial or a study anything
published in a journal but but good
ideas things that make sense
that's the stuff that sits in the flesh
of this olive the olive is stuffed with
a pepper and the pepper contains the
subset of those interventions that
you've all written down for which we do
in fact have some pretty robust evidence
that they work that pepper is then
stuffed with a very very small piece of
garlic which is the subset of those
interventions for which we have evidence
of effectiveness for which we also have
evidence of cost-effectiveness but as
I've said this is a dangerous olive and
there are concerns I think about the
kinds of things that sit within the
pepper and the guard
the kinds of interventions for which we
have evidence of effectiveness and I'd
like to try and explain why one way of
thinking about obesity is that we need a
huge range of actions at all levels of
society throughout the life course at
multiple different levels of the system
from individual level treatments such as
bariatric surgery all the way up to
reform of the Common Agricultural Policy
oh it's it's like building a wall of
sandbags against a flood but all too
often in our research what we do is we
take one sandbag out from that wall and
we might even put it in a randomized
control trial and we assess it to see if
it stops the whole flood does this
intervention on its own have an effect
on the distal outcome of obesity in many
cases we find that it doesn't but we're
judging those interventions on the wrong
criteria you wouldn't expect anyone
sandbag to stop a flood we should test a
sandbag in terms of its effectiveness at
being a sandbag not as an entire wall so
if we look at this diagram which is
adapted from one that Boyd Swinburne
used in a 2011 Lancet paper on obesity
there's a range of interventions that we
can put into place on the right hand
side we've got those individual level
interventions such as drugs or surgery
and on the left hand side we've got very
upstream policy interventions
agricultural policy taxes on sugar fat
and so on at its most extreme perhaps a
really significant tax on carbon
emissions which would affect the ways in
which we move around the kinds of foods
that get produced and so on and in the
middle we have in general the kind of
things that relate to our local
environment the numbers of fast-food
outlets on our high streets the
provision of cycle lanes or high quality
infrastructure for walking in our towns
and cities so very very broadly in this
diagram what we've got is on the left
hand side the kinds of interventions and
actions that can be taken by national
government around the middle we have the kind
kind
of interventions and actions that can be
taken by local or regional government
and on the right hand side we have
actions for the Health Service and also
for individuals and there's a there's a
wedge across the bottom there that says
population effect and political
difficulty and what we find is that the
individual level interventions can be
extremely effective in any one
individual but a population effect they
tend not to be practical at shifting the
population bariatric surgery surgery for
obesity is a very very effective
intervention in the right individuals
but we've got around one and a half
million people with a body mass index
over 40 in this country very very rough
measure of need I'm not for a moment
saying that all those people should have
surgery but as a very rough indication
we've got about 1 and a half million
people who might benefit but we do
something like 6 or 7 thousand of those
operations a year great intervention in
the right individual but it's not a
population level response on the
left-hand side of the diagram we've got
big picture population level actions
agricultural policy the kinds of things
that determine the amount of sugar and
fat flowing into our food system actions
to shift that are politically extremely
difficult to do but they could have big
picture impacts on on the distribution
of body weight across society and then
I've added three more little wedges
across the bottom all skewed over to the
right evidence base is skewed towards
the individual level public political
and media discourse is also skewed
towards the individual and as a result
political mandate is skewed towards the
individual so this is why the olive that
I showed you earlier is dangerous
because the kinds of things that sit
within the pepper and the garlic are the
kinds of things that sit on the right
hand side of this diagram it's not to
say that they're not helpful they are
they're an important part of the picture
but if that's all we do and we ignore
the more upstream things over to the
left hand side we're missing some of the
potentially most effective and most
powerful interventions there's another
aspect to this which comes from
an academic who was at my institution
the London School of Hygiene called
Geoffrey rose and Rose talked about the
difference between the population level
interventions and the targeted
interventions in high-risk populations
and one of the consequences of using
words like obesity is that we tend to
think about people at the the far end of
the population distribution people who
are perhaps candidates possibly for
surgery but what Rose pointed out is
that many of the interventions that we
could be doing to tackle population
level problems don't just involve
targeting specific individuals with with
highly with with big effect
interventions such as surgery they may
be about making very very small changes
change is so small that you couldn't
actually detect their impact impact in
any one individual but if you aggregate
them up across the entire population you
shift the distribution across that
population over to the left so we could
reduce everyone's weight by a small
amount you might not even be able to
pick that up at individual level but
across the population you would have
improvements in health across large
numbers of people so what's this got to
do with complexity and I think before
that question can be answered it's
important to grasp what we mean by
complexity because often I think the
idea of things that are very complicated
is confused with things that are complex
now there are lots and lots of different
ways of defining these words but one of
the ways that I find really helpful is
to use this analogy of a space rocket a
Saturn 5 rocket this is an incredibly
complicated piece of equipment
incredibly detailed thousands and
thousands of parts to it it would take a
very long time to build one but if you
know what you're doing you can put three
people into that little cone at the top
send it to the moon and whatever it is
five or six days later you know exactly exactly
exactly
where to pick those people up from in the
the
so it's a it's a hugely complicated
thing but it is predictable it is
controllable you press a button to
launch it and five or six days later you
know - within a minute or two and within
a few hundred meters where it's going to
end up geopolitical relationships in the
Middle East however or a rather
different category of problem and this
is what a complex problem looks like if
you intervene in any one part of this
what you find is that there are
unpredictable effects there are linkages
across this entire system this is not a
system or problem that one can solve
because a complex problem in general
isn't something that one can solve a
complex problem is something that one
can intervene in to create a
reconfiguration and lead to changes and
and a different potentially a different
set of outcomes but all too often we
conceptualize problems that look like
this as if they look like the space
rocket we even in Health Services talked
about the delivery chain as if there was
a link going to a link going to a link
going to a link when in fact we have a
whole load of interacting elements that
influence one another and things change
as things move so at the heart of
grappling with complexity is
understanding that we don't necessarily
have these kind of straight direct
linear relations between cause and
effect that much of our scientific
thinking has taught us to think about
and I've been involved in some work in
in a city recently where we've looked at
using this approach for thinking about
physical activity we've mapped out the
physical activity system and here is a
first stab at it we went for a moment
pretending that this was a definitive
definition of all the things that sit
within physical activity in a local
authority but it was a tool a way of
encapsulating some of the important
things that can be done at local
authority or at local authority level
to promote increased activity across the
population and very broadly on the
right-hand side of this diagram we've
got individual level actions providing
people with information social marketing
schemes and so on on the left-hand side
we've got more structural things cycle
lanes and so on and so forth and in the
middle we've got the kinds of things
that get measured levels of walking in
cycling and so on and so forth we've
worked with people in this local
authority and we said we're draw on this
map the kinds of things that you think
would be really helpful to do to
increase the level of walking and
cycling and physical activity in general
and and they highlighted a whole load of
activities in that structural area on
the left hand side we then got them to
map out the kinds of things that they
were currently focusing on and that was
the kinds of things that were on the
right hand side so merely by mapping out
the system and working with a group of
stakeholders to examine what bits of the
system were being acted on and what bits
were not being acted on it was possible
to identify potential areas for changing
activity for bringing near activity in
and so forth and we used it much more
than this we looked at data that could
be measured for example the kinds of
things that were already being collected
and other things that one might collect
over time to identify changes within
this system and time I think is a really
important dimension dimension that we've
often lost sight of in public health
when we're thinking to come back to
childhood obesity when we're thinking
about how we act to tackle childhood
obesity many of the things that we focus
on initially deal with understandably
and appropriately the problems of health
the health problems that arise during
childhood of course
when one wants to make sure that
children who have a weight problem are
not subject to stigma or bullying or or
physical health problems
and if we go back to the ollie of what
we find is that there are some areas in
which we do have some evidence that the
things that sit within the pepper and
the garlic that relates to this domain
the next thing we look at is the idea
that obesity in childhood tracks into
adulthood if you if you're overweight as
a child and as an adolescent it's more
likely that you will be overweight as
you go into adult life so of course
reducing the weight the weight status of
children during childhood is a helpful
thing to do it reduces the likelihood of
long-term that long-term gain but what
we all too rarely look at is the kinds
of interventions that might be
introduced in childhood that could
affect not just what happens to that
child during childhood or their weight
status at the end of childhood but
actions that might affect their behavior
across the life course one way of
thinking about this is to use the
example of a walking school bus and my
kids used to do a walking school bus you
drop them a bit of away from the school
maybe half a mile or so they walk in a
group we're wearing a hybrid Tabard said
that they're safe on the roads and they
might burn an extra twenty or thirty
calories a day at one level one might
say twenty or thirty calories a day big
deal what's this really going to do well
actually I think if you can find five
six or ten other things where those kids
burn 20 or 30 other calories a day
that's two or three hundred calories and
that's that really is a big deal so I
don't think it should be dismissed
merely on the fact that the energy
expenditure of this intervention isn't
so much but my sense is that some of the
more important impacts of something like
a walking school bus may be wider system
effects the fact that if you have a
cohort of children who get used to
walking to school every day they get
used to the idea of walking whatever the
weather snow rain windy they can just
get used to it it normalizes walking you
might get a cohort of parents who are particularly
