Evaluation of the coverage of linked Canadian Community Health Survey and hospital inpatient records.

BACKGROUND: Evaluation of the coverage that results from linking routinely collected administrative hospital data with survey data is an important preliminary to undertaking analyses based on the linked file.

DATA AND METHODS: To evaluate the coverage of the linkage between data from cycle 1.1 of the Canadian Community Health Survey (CCHS) and inpatient hospital data (Health Person-Oriented Information or HPOI), the number of people admitted to hospital according to HPOI was compared with the weighted estimate for CCHS respondents who were successfully linked to HPOI. Differences between HPOI and the linked and weighted CCHS estimate indicated linkage failure and/or undercoverage.

RESULTS: According to HPOI, from September 2000 through November 2001, 1,572,343 people (outside Quebec) aged 12 or older were hospitalized. Weighted estimates from the linked CCHS, adjusted for agreement to link and plausible health number, were 7.7% lower. Coverage rates were similar for males and females. Provincial rates did not differ from those for the rest of Canada, although differences were apparent for the territories. Coverage rates were significantly lower among people aged 75 or older than among those aged 12 to 74.