Human Error Assessment and Reduction Technique - Disadvantages

Disadvantages

• The main criticism of the HEART technique is that the EPC data has never been fully released and it is therefore not possible to fully review the validity of Williams EPC data base. Kirwan has done some empirical validation on HEART and found that it had “a reasonable level of accuracy” but was not necessarily better or worse than the other techniques in the study. Further theoretical validation is thus required.
• HEART relies to a high extent on expert opinion, first in the point probabilities of human error, and also in the assessed proportion of EPC effect. The final HEPs are therefore sensitive to both optimistic and pessimistic assessors
• The interdependence of EPCs is not modelled in this methodology, with the HEPs being multiplied directly. This assumption of independence does not necessarily hold in a real situation.