Reliability of collecting colorectal cancer stage information from pathology reports and general practitioners in Queensland

Abstract

Objective: To investigate the reliability of
collecting colorectal stage information from
pathology reports and general practitioners
in Queensland, Australia.-----
Methods: A longitudinal study of colorectal
cancer survivors conducted in 2003 and
2004 (n=1966, response rate=57%)
obtained stage information from clinical
specialists (n=1334), general practitioners
(GP) (n=1417) and by extracting stage
from pathology reports (n=1484). Reliability
of stage information was determined by
comparing stage from GPs and pathology
reports with that reported by the clinical
specialists, using a weighted kappa.-----
Results: GPs and pathology reports each
had a similar level of agreement with
clinical specialists, with kappa scores of
0.77 (0.75-0.80) (n=1042) and 0.78 (0.75-
0.81) (n=1152), respectively. Results were
similar when restricting to records staged
by all three methods (n=847). GPs had
similar levels of agreement with clinical
specialists within each stage, although
pathology reports tended to under-stage
patients in Stage D (0.37). Collapsing
stage into two categories (A or B, C or D)
increased the reliability estimates from the
pathology reports to 0.91 (0.88-0.93), but
there was little change in GP estimates
0.79 (0.75-0.83).-----
Conclusions: Extractions from pathology
reports are a valid source of broad stage
information for colorectal cancer.
Implications: In the absence of clinical
stage data, access to pathology records by
population-based cancer registries enables
a more accurate assessment of survival
inequalities in colorectal cancer survival.