the power of surface modelling

The Power of Surface Modelling

Bryan Clarke

2015 HiNZ Conference

Thanks to ….

Overview

• Mapping 101 using John Snow’s Cholera discovery in 1854• Trend mapping for KPIs to look for opportunities for improvements• Localised mapping of a pharmacy to look at market penetration• Specific medication mapping using trend and penetration mapping

Progress since John Snow

Thematic Mapping• Boundaries are arbitrary• Boundaries don’t change

as the underlying data changes

• Boundaries are often related to non-healthcare functions (eg voting, rating)

• Uncommunicative and statistically invalid

Transactions or trends?

Scenario One: Regional Example

Where can the KPIs be improved to the greatest effect?

Life Threatening Incidents(1 month)

● Met target (1)

● Missed target(0)

Percentage Surface● 100%● 0 %

Incident Density Surface ● Highest density● High density

Bang for Buck Surface ● Highest opportunity● High opportunity

Scenario Two: Specific PharmacyExample

http://www.stats.govt.nz/Census/2013-census.aspx

Population Density● Highest density● Lowest density

Patient Density● Highest density● Lowest densityϨ 500m Driving distance contours Scale: Kilometres

Market Penetration● 60% penetration● 10% penetration

𝑀𝑎𝑟𝑘𝑒𝑡 𝑃𝑒𝑛𝑒𝑡𝑟𝑎𝑡𝑖𝑜𝑛=𝑃𝑎𝑡𝑖𝑒𝑛𝑡𝐷𝑒𝑛𝑠𝑖𝑡𝑦 /𝑃𝑜𝑝𝑢𝑙𝑎𝑡𝑖𝑜𝑛𝐷𝑒𝑛𝑠𝑖𝑡𝑦Scale: Kilometres

Driving distance● Closest to pharmacy● Farthest from any pharmacy (4km)

Driving distance fromBastins● up to 500m● up to 1km● up to 1.5kms

Customer growth● Greater opportunity● Reduced opportunity

Scenario Three: Specific SmokingMedication Example –Champix vs Habitrol

Population Density● Highest population● Lowest population



UrbanSmokerDensity● Highest density● Lowest density


UrbanSmokerPercentage● 35% ● 5%

Market Penetration● 60% penetration● 10% penetration

Scale: Kilometres

Ratio● Champix ● Habitrol

Ϩ Pharmacymarket contours (5% intervals)

Scale: Kilometres


Deprivation● Least deprived● Most deprived

Scale: Kilometres

http://www.stats.govt.nz/Census/2013-census.aspxScale: Kilometres


Deprivation● Least deprived● Most deprived

Scale: Kilometres


● High smoker density ● Low smoker density http://www.stats.govt.nz/Census/2013-census.aspx

Advantages of Surface Analysis• Computation is not particularly intensive• Easy to understand• Easy to compare different data sets• Anonymise the data (without the need for meshblocks)• Communicative• Can be statistically validated• Automated and served up from the cloud

the power of surface modelling

Healthcare