Table 3

Cluster Analysis of Higher Grade* Prostate Cancer Cases – Maryland Cancer Registry, 1992–1997


Radius (km)
# Block groups in Cluster
# Higher Grade Cases Expected
# Higher Grade Cases Observed
Relative Risk
P Value

Map 2. Unadjusted Analysis






     Cluster 1
5.99
550
522.5
669
1.28
.001
     Cluster 2
44.93
201
305.3
210
0.69
.001
     Cluster 3
10.34
173
253.9
176
0.69
.004
     Cluster 4
5.93
38
93.8
49
0.52
.017
Map 3. Adjusted Analysis **






     Cluster 1
14.81
292
487.3
362
0.74
.001
     Cluster 2
54.65
162
247.6
164
0.66
.003
     Cluster 3
8.27
80
99.6
156
1.56
.013
Map 4. Adjusted Analysis ***






     Cluster 1
6.02
554
444.0
643
1.45
.001
     Cluster 2
48.62
1181
1825.4
1587
0.87
.001
     Cluster 3
30.88
99
155.8
94
0.60
.004

* Among cases with a histologic grade, those cases graded as 3 or 4 vs. 1 or 2.

** Expected Rate Adjusted for Race, Age, Year of Diagnosis.

*** Expected Rate Adjusted for Age, Race, Year of Diagnosis, and Area-Level Census Characteristics.

Klassen et al. International Journal of Health Geographics 2005 4:1   doi:10.1186/1476-072X-4-1