Mapping with GIS

Mapping with GIS:
The Case of the SWO Children’s Health Atlas
Jason Gilliland
Departments of Geography, Health Sciences, & Paediatrics
Sandra Kulon
Human Environments Analysis Laboratory (HEAL)

Discussion Overview
What is GIS?
How does it Work
Key Concepts
Building a GIS
People/Data/Software/Hardware
GIS Case Study: Putting Children on the Map
The benefits of GIS in Children’s Health Research

What is GIS?: Formal Definition
Geographic Information System (GIS)
A computer based system to aid in the collection, maintenance, storage, analysis,
output and distribution of spatial data and information.
Bolstad (2012)

What is GIS?
A Database attached to map
Average Income
In Dollars
< 45,000
45,000.1 - 65,000
65,000.1 - 85,000
85,000.1 - 100,00
> 100,000

What is GIS?
A Database attached to map
Unemployment Rate
< 2
2.1 - 5.0
5.1 - 10.0
10.1 - 15.0
15.1 - 28.1

What is GIS?
Allows us to dynamically map various attributes from a
table.
Senior Citizens
% of Population
< 2
2.1 - 5.0
5.1 - 8.0
8.1 - 10.0
< 10

Building a GIS
Components of a GIS
People
Data
Hardware
Software

Components of GIS: People
Understand how geographic data is
to be compiled and managed
Decide how data is to be collected
Make the analysis decisions
Provide the comprehensive and
interpretative component

Components of GIS: Data
The Power of GIS lies in constructing various data layers
that help model your study area

Components of GIS: Data
Data is obtained from several different sources
Geomatics Organizations
DMTI, First Base Solutions, NTDB
GPS
Collecting your own data
Remote Sensing
Extracting land information from Satellite Imagery
Digitizing
Using existing paper maps and making them digital
Accuracy of Data determines how powerful of a tool your GIS
is
Garbage in: Garbage Out
Often, more than 2/3 of the time to complete a GIS project
is spent on data preparation!

GIS in:
Human Environments Analysis Laboratory
Multi-Disciplinary Research Lab that uses GIS to:
Study relationships among environmental, economic, and
social factors, with the overall goal to:
identify effects of environmental factors (social and physical) on
population health and quality of life;
offer comprehensive solutions and support work of
municipalities, health units and non-profits;
improve planning and design of communities, to promote
health and quality of life for all.

Case Study:
A Children’s Health Atlas for SWOntario

Context:

Context:

People:

People:

People:

People:

People:

People: The Social Environment

Places: The Physical Environment

Patterns: Linking Environment & Health

Linking Foodscapes to Diet, Obesity & Health
• Obesity linked to diet of ‘fast’
foods 1
• High density of fast-food outlets
linked to unhealthy diet, obesity,
& related diseases 2
• Fast-food more prevalent in
poor neighbourhoods &
supermarkets more scarce 3
1
Ebbeling et al, 2002; Zive et al, 2002; Bowman et al, 2004; 2 Alter & Eny 2005; He et al, 2010;
3
Reidpath et al, 2002; Block et al, 2004; Austin et al, 2005; Larsen & Gilliland 2008

Mapping Evolution of a “Food Desert”
Neighbourhoods with poor access:
• households pay more for healthy food
• higher levels of food insecurity
• adults poorer diets, poorer health
(evidence NA for children)
Larsen & Gilliland 2008; 2009

Junk Food & Children’s Environments
London, Ontario
Junk food proximity:
• mean distance = 400m
Gilliland 2010; He et al 2011ab; Gilliland et al 2012

Junk Food & Children’s Environments
London, Ontario
Junk food density:
• highest around low SES schools
• influences purchasing,
consumption & BMI
Gilliland 2010; He et al 2011ab; Gilliland et al 2012

Physical Activity & Public Recreation Spaces
• Access to public parks & rec
facilities linked to ↑ PA &
↓obesity , especially for youth 1
• Parks are typically of poorer
quality in low-income areas 2 and
poor quality parks are rarely
used 3
• Walking leads to ↑ PA ↑ health, 4
walking/biking influenced by
environmental factors 5
1
CLFI 2009; Tucker et al, 2008; Huston et al., 2006; 2 Wolch et al. 2005; Coen & Ross, 2005;
3
Gilliland et al 2010; 4 Sesso et al, 1999; Lacroix et al, 1995; Oja et al, 1998; 5 Larsen et al 2009

Access to Public Recreation Spaces

Public park accessibility, quality and use
N=235
School survey:
• Greater access to
public rec opps linked
to more time spent on
MVPA & lower BMI
Park Quality Index:
• playground facilities
• sporting facilities
• comfort facilities
• aesthetics
Play Space
Needs Index:
Play Space Needs Level
• household income
• lone-parenthood
• household crowding
• dwelling type mix
• youth density
Gilliland et al 2006; Gilliland et al 2008; Tucker et al 2009; Gilliland et al 2012

Environmental Influences on Walking to School
Environmental indicators:
Distance between home & school
Land use mix
Density of street trees
Intersection density (‘connectivity’)
Number major streets crossed
Traffic volume
Retail density
Residential density
Dwelling type mix
Number railroads crossed
Sidewalk coverage
Pathway coverage
Streetlight coverage
Route directness
Crime along route
Larsen et al 2009, 2012

Environmental Influences on Walking to School
Environmental indicators:
Distance between home & school
Land use mix
Density of street trees
Intersection density (‘connectivity’)
Number major streets crossed
Traffic volume
Retail density
Residential density
Dwelling type mix
Number railroads crossed
Sidewalk coverage
Pathway coverage
Streetlight coverage
Route directness
Crime along route
Larsen et al 2009, 2012

Benefits of GIS
• Ability to manage and manipulate many massive datasets!

Benefits of GIS
• Quickly raise and test hypotheses, and to uncover
relationships which would otherwise be indiscernible!

Benefits of GIS
• Powerful analytical tools to discover, quantify, and
visualize spatial patterns!
E.g. ‘Model Builder’ helps us manipulate
large datasets and re-test hypotheses
E.g. ‘KDE’ one way to measure
and visualize density of spatial
phenomena

Recommendations
• GIS is fundamental for research and decision-making…
• Always carefully plan a project …
• Know your data limitations …
• Know your geography … hire a geographer!

Thank you…
For further info on GIS at Western:
• Geography Dept: GIS courses (www.uwo.ca/geog)
• Equinox: GIS data (http://equinox.uwo.ca)
• Map and Data Centre: (http://www.lib.uwo.ca/madgic)
• Human Environments Analysis Lab: (www.spatialists.com)
• Dr Jason Gilliland: advice (urbanprof@gmail.com)