José ApontePublic Health Advisor

Module 7: Mapping12 June 2012

Epi Info™ 7 Introductory Training

Office of Surveillance, Epidemiology, and Laboratory ServicesEpidemiology and Analysis Program Office

Learning Objectives

After completing this module the participant will be able to:

Understand the fundamental concepts of Epi Map Familiarize with the Epi Map workspace Generate Case Cluster and Choropleth maps Understand some of the geo-referencing concepts Save images of maps

Launching Maps from EnterEnter can geocode addresses into latitude and longitude. A ‘Map’ button on the toolbar will open the maps module with this data already loaded. Internet access is required both to load the maps module and for geocoding.

Launching Maps from the MenuYou can also run the maps module right from the menu, but no data will be pre-loaded. Internet access is required.

Getting started with maps…

“Maps” Navigation Pane

Quick Start Guide Figure 5.2 Click Add

data layer Case Cluster

Click HIV.prjCase

Click “No” external data

Select Latitude & Longitude from the drop downs

Change satellite to Street

Quick Start Guide Figure 5.2 Resulting

map Zoom in to

Atlanta city (where the large dot with 117 cases is)

Use the navigator to do this

Zoom in to ATL

Hover over a dot with multiple cases

Click on a dot to get information about the case

Quick Start Guide Figure 5.3 & 5.4

Quick Start Guide Figure 5.5 & 5.6

More advance options include data filtering, and stratifying.

Adding choropleth layers with cenus info as the theme

Quick Start Guide Figure 5.7

• Set a filter

• Use age < 21

Quick Start Guide Figure 5.8

• Add the case layer again

• This time filter for age > 21

Quick Start Guide Figure 5.9 Resulting

map shows cases stratified by age

Note Map Gadget shows 2 layers

Other Features/Demos of “Maps” Create Time Lapse Save map project (updates as new data is

added) Save map image (paste into reports,

presentations) Right click map to add point marker, zone,

or label Add external Data Layer

Try a choropleth layer so you can demo changing colors Must have at least one geographic variable to link files

Add external Reference Layer (from map server) May use an internal/agency map server May use an external/public domain map server

INSTRUCTOR-LED DEMONSTRATION

Case Cluster Maps

Creating Choropleth Maps

Creating Choropleth Maps EPI Map can also represent data in a map to

interact with files shapefile data fields (.SHP) containing geographical locations.

Shapefiles files may also contain data on populations and other variables, and therefore can provide numerical data that form part of the representation.

Basic Mapping Rules There must be a geographic field in the

dataset that corresponds to a shape file.

Data to be mapped must be aggregated to a unique geographic field.

  Data being plotted must be in numeric

format

Shape Files .SHP contains polygon, line, or point

coordinates

.DBF contains names of features and optional info like population, area, alternate code systems, etc., in dBASE format

.shx, .sbn, .sbx files may or may not be included

All 5 (.DBF,.SHP,.SHX,.SBN,.SBX) files must be present, although they are referred to as one “shape file

INSTRUCTOR-LED DEMONSTRATION

Choropleth Maps

For more information please contact Centers for Disease Control and Prevention1600 Clifton Road NE, Atlanta, GA 30333Telephone, 1-800-CDC-INFO (232-4636)/TTY: 1-888-232-6348E-mail: cdcinfo@cdc.gov Web: www.cdc.gov

Questions?

Office of Surveillance, Epidemiology, and Laboratory ServicesEpidemiology and Analysis Program Office

The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention.