Cardiovascular Access · Canada · Geometric Centroids

Drive Time to Nearest PCI-Capable Hospital — Geometric Centroids

Distance measured from the geometric centroid of each census division — the mathematical midpoint of the land area. For Canada’s massive northern and rural census divisions, this places the measurement point in uninhabited wilderness, dramatically overstating the true distance to care. Compare with the population-weighted centroid map.
<30 min7.4% of regions
30–90 min20.9% of regions
>90 min71.6% of regions
72%
of census divisions beyond 90 min
using geometric centroids
7%
of census divisions under 30 min
CDs containing a PCI center
30
PCI-capable centers nationally
CIHI & provincial directories
0
PCI centers in PEI, Yukon,
NWT, or Nunavut

Geometric Centroids and the Canadian Geography Problem

Canada’s census divisions are often enormous — Nord-du-Québec alone is larger than France. Its geometric centroid sits in the subarctic, over 700 miles from the nearest PCI center. The three territories have zero PCI access regardless of centroid method. Even southern census divisions like Thunder Bay District in Ontario have geometric centroids deep in boreal forest, far from the hospital that sits within their borders. Census divisions containing a PCI center are classified as <30 min. This map uses the naive approach to contrast with the population-weighted version.

Data: PCI centers from CIHI Cardiac Care Quality Indicators and provincial cardiac program directories (30 centers). Distance from geometric census division centroids to nearest PCI center via haversine formula. Drive time: miles × 1.3 road factor ÷ 45 mph + 15 min overhead. Census divisions containing a PCI center are classified as <30 min.

Visualization by Anish Koka MD · AnishKokaMD.Substack.com