center and treatments are provided sequentially in accordance with a workflow step 82 upon detection of a key performance indicator event step 84 the kpi record equivalent to the abandonment record described in respect of fig3 is updated with details of the last treatment or of the history of treatments provided to that caller step 86 along with relevant details of the kpi event total sales dollar amount or identifier of product s sold or the fact that the caller was ultimately referred to a supervisor if in decision 88 the cumulative correlation between kpis and treatments are evaluated for significance if they are not evaluated as having been significant i e the treatments played to a set of callers do not have a statistically positive or a negative correlation with a measured kpi then no action is needed step 90 and the process reverts to step 80 if however the kpi changes are evaluated as significant in accordance with the programmed rules for such an evaluation then the process proceeds to decision 92 in which an evaluation is made as to whether the treatments have improved the kpi or not if the kpi is improved such as for example if a positive correlation is noted between ancillary sales and the playing of a particular advertisement or the playing of a particular piece of music prior to an ivr session then in step 94 the treatment providing the positive influence is flagged for promotion if on the other hand the evaluation in decision 92 is negative.