Continuous opportunistic and systematic screening for hypertension with computer help: analysis of non-responders.

For two years an office computer was used to identify patients to prompt for opportunistic screening and call for systematic screening. After the two years 92% of patients on the list had had blood pressure readings recorded within the previous five years, of which 34% resulted from special prompts and 22% from screening letters. Those who failed to respond to letters were sent questionnaires, and their records were compared with those of screened patients. With the help of a microcomputer it is practicable to sustain a continuous screening rate of between 90% and 95%.