Use of interval based quality indicators in blood pressure management to enhance quality of pay for performance incentives: comparison to two indicators from the Quality and Outcomes Framework.

BACKGROUND

Pay for performance incentives are becoming increasingly popular, but are typically based on only a single point-in-time measurement as an indicator of chronic condition management.

AIMS

To determine the association between three time-interval based indicators of suboptimal blood pressure (BP) control and two point-in-time indicators from the UK Quality and Outcomes Framework (QOF): BP5 (the percentage of patients with hypertension in whom the last BP in the previous nine months was < or = 150/90) and DM12 (the percentage of patients with diabetes in whom the last BP in the previous 15 months was < or = 145/85).

METHODS

We extracted classification data and BP measurements from four New Zealand general practices with 4260 to 6130 enrolled patients. Data were analysed for three indicators with respect to a nine-month evaluation period for patients with hypertension and a 15-month period for patients with diabetes: (1) two or more consistently high BP measurements spaced over > or = 90 days, (2) a high BP measurement followed by a lapse of >120 days in BP measurement and (3) no BP measurement for >180 days.

RESULTS

For the four practices, 65-81% of the patients satisfied BP5 and 59-68% of patients satisfied DM12. Of the hypertension patients satisfying BP5, 31% (95% CI: 28-33%) failed at least one of the three interval based indicators; 42% (95% CI: 39-46%) of the diabetes patients satisfying DM12 failed at least one of the three interval based indicators.

CONCLUSION

Considering only a point-in-time controlled BP measurement provides an incomplete view of the quality of BP management in patients with hypertension or diabetes over a period of time.