Table 1.

Relative Strengths of Comorbidity Data Sources

Data Feature	Existing Clinical Trial Data	Prospective Cohorts of Cancer Patients	Retrospective Chart Review	Administrative Data	Linked Tumor Registry Administrative Data
Representative data set (reference No.)	Meyerhardt et al (20)	Prostate Cancer Outcomes Study (25)	Adult Comorbidity Evaluation-27 (10)	State and other hospital discharge data sets (31,32)	SEER-Medicare (33)
Captures severity of illness	++	+++	+++	+	++
Information on comorbidity	++	+++	+++	+	+
Complete cancer information	++++	+++	+++	-	+++
Captures other patient information (functional status, social support)	++	+++	+	+/−	+/−
Generalizability	+	++	++	++++	++++
Cost	+	++++	++	+	+

NOTE. + indicates “least”; ++++ indicates “greatest.”

Abbreviation: SEER, Surveillance, Epidemiology, and End Results.