Fig. 2

Left: Relationship between an individual’s satisfaction score and probability of response. The dots represent nodes where the slope is allowed to change (satisfaction scores of 3, 5, 7, 9, 9.5). Right: Plot of the mean statisfaction score observed in responders and predicted by the model among all invited persons (responders and non responders). Each survey is represented by a circle. The diagonal line is the identity line, and the vertical distance between a circle and the identity line corresponds to non-response bias