Figure 2

Comparing change in performance in two areas: one with an intervention and one without*. * The Figure illustrates that attributing the change from 'Baseline' to 'Follow-up' in response to an intervention is likely to be misleading. This is because, in this instance, there is also an improvement in the 'Control'. Even with regard to the Control, it is uncertain whether the difference between the 'Intervention' and 'Control' (i.e. the 'Impact') can, in fact, be attributed to the programme or intervention. There may be other differences between the 'Intervention' and 'Control' settings that might have led to the observed difference in the indicator measured