Study designs of evaluations included in the review
The inclusion criteria specified studies using a controlled trial design.
Specific interventions included in the review
The inclusion criteria specified interventions using mass mailings direct to Medicare beneficiaries to increase the uptake of influenza vaccination. The authors stated that mass mailings are not the same as reminders sent by the patient's clinic or personal physician. The specific interventions included personalised letters, form letters, postcards, letter and brochure, or no mailing.
Participants included in the review
The inclusion criteria specified Medicare beneficiaries. The Medicare participants were aged 65 years or older.
Outcomes assessed in the review
The reviewers did not specify any inclusion criteria for the outcomes. The reported outcome was the change in the rate of the Medicare beneficiaries' response to the mass mailings.
How were decisions on the relevance of primary studies made?
Two physician reviewers selected studies for the review and resolved any disagreements by consensus.