Current issues of ACP Journal Club are published in Annals of Internal Medicine

Quality Improvement

A poster graph tracking system in private practice increased influenza immunization in elderly patients

ACP J Club. 1991 Sept-Oct;115:63. doi:10.7326/ACPJC-1991-115-2-063

Source Citation

Buffington J, Bell KM, LaForce FM, and the Genesee Hospital Medical Staff. A target-based model for increasing influenza immunizations in private practice. J Gen Intern Med. 1991 May/Jun;6:204-9.



To assess the effect of a poster graph tracking system on influenza immunization rates of elderly patients seen in private physicians' offices. The goal for immunization was ≥ 60%.


Randomized controlled trial.


13 private practices with 45 physicians in the Rochester, New York, USA, area participating in a Medicare Influenza Vaccination Demonstration Project from September to December, 1989.


Patients were ≥ 65 years of age and had been cared for at least once in the office of a physician affiliated with the Genesee Hospital within the previous 2 years. Of 56 eligible physicians, 45 agreed to participate. The 13 practices were stratified by size and randomized to group 1 (control, 17 physicians), group 2 (poster, 13 physicians), or group 3 (poster and postcard, 15 physicians). Group 1 had 4772 patients (aged ≥ 65 y), group 2 had 2149, and group 3 had 3604.


Physicians in groups 2 and 3 attended an introductory information session, then were sent posters on which weekly and cumulative immunization totals were graphed. The posters were to be prominently displayed. In addition, patients in group 3, were mailed a postcard reminder. Group 1 had no intervention. Immunization vaccine was provided free for all patients, either at the physician's office or at public clinics.

Main outcome measure

Percentage of patients who were immunized against influenza, obtained from billing records.

Main results

All intervention practices complied with graph completion. 66% and 67% of patients were immunized in groups 2 and 3, respectively, compared with 50% in group 1 (P < 0.001 for both comparisons with group 1). 34% of group 1 patients, compared with 50% for group 2 and 54% for group 3, were immunized in their physicians' offices (P < 0.001 for both). 16% of both group 1 and group 2 patients were immunized in a public clinic, compared with 13% of group 3 patients (P < 0.001). Postcard reminders increased office immunizations by 8% (P < 0.01), but when overall rates (office plus public clinic) were compared, this difference dropped to < 2% and no difference was seen between groups 2 and 3.


A poster graph tracking system, prominently displayed, increased rates of immunization against influenza among the patients (aged 65 years or older) of physicians in private practice to above the target rate of 60%. Additional mailing of postcards to the patients did not affect overall rates of immunization.

Source of funding: Not stated.

Address for article reprint: Dr. F.M. LaForce, The Genesee Hospital, 224 Alexander Street, Rochester, NY 14607, USA.


This study provides important evidence that it is possible to increase vaccination rates in private group practices. However, higher-than-expected rates were seen in the control group and in the intervention groups, and unfortunately the study design does not allow determination of which intervention was responsible for the increased rates. There were several additional interventions in study groups 2 and 3: a baseline information session; visits by project staff and visits every 2 weeks to monitor charting, and the charting itself in both groups; and a postcard reminder to patients in group 3. In all 3 groups, there were 3 interventions not typically seen in U.S. private practices: baseline identification of the target population, the availability of free vaccination, and auditing at the end of the study for compliance with vaccination in the target group.

We do not know from the results of this study whether postcards alone might have been as effective as charting alone, because no group received only the former intervention. We are not told if the postcard reminder was neutral or addressed health beliefs. (As cited by the authors, the latter approach has been found to be associated with a higher vaccination rate.) We are not told if any of the practitioners were in solo practice. The findings may not be generalizable to such settings because, as the authors note, competition occurred among practitioners in the practices. We do not know whether the experimental interventions would have been less effective, equally effective, or even more effective in a setting where vaccination was not free, and whether we would have seen a difference between the 2 intervention groups.

Despite these limitations to generalizability, this paper should serve as a stimulus to programs to increase immunization roles in private practice settings.

Martin F. Shapiro, MD
University of CaliforniaLos Angeles, California, USA