4.7 Determining if Treatment Data Are Different Than Baseline Predicts

In single-subject research, basic effects provide evidence that the intervention might have caused a change in the behavior. We identify a basic effect when the treatment data are different from what we would have predicted based on baseline. Remember, the purpose of baseline is to predict what would happen if baseline continued. To do this, we first estimate the slope in the baseline phase and extend that into the treatment phase. Then, we’ll compare the data in the treatment phase to what we predicted would happen if baseline continued.