Table 2

Patients Screened, Chart Audit Data

MeasureControl Practices (n=11)Intervention Practices (n=12)
Odds of improvement
 OR (95% CI)a0.80 (0.58–1.12)1.17 (0.86–1.59)
 OR=1, P valueb.18.32
 Breslow-Day, P value<.001.001
 Ratio of ORsc1.45
 Equal ORs, P value.10
Change in performance
 Average difference of proportions (95% CI)d−0.05 (−0.20 to 0.09)0.04 (−0.09 to 0.17)
 Change within group, P value.44.56
 Intervention effect, P value.33
  • OR = odds ratio, interpreted as the odds of screening at follow-up relative to the odds of screening at baseline.

  • a P value testing the null hypothesis of no improvement within group.

  • b P value testing whether the odds of improvement are homogeneous across practices within a group.

  • c Calculated as the odds of improvement under the intervention relative to the odds of improvement for the control group.

  • d For each practice, change was measured as the proportion screened at follow-up minus the proportion screened at baseline.