Background The laws providing the framework for acting and making decisions on behalf of adults who lack capacity in Hong Kong is mainly the Mental Health Ordinance (MHO). As a local geriatrician practising in a public hospital, we find that there are difficulties for the frontline healthcare workers in applying the laws.

Aim Improve the frontline healthcare workers in assessing the mental capacity of the elderly.

Methods We study a case, Mr. Au, aged 84 years old, nursing home resident, who had recently suffered from complete heart block but refusing pacemaker insertion. As a result of limited knowledge of the frontline healthcare workers in assessing his mental capacity and apply the laws principles, he had repeatedly admitted to hospitals for several times. We went through a literature research and compare our laws system with that in England and Wales, particularly the Mental Capacity Act (MCA 2005). Then we educate the results to the frontline healthcare workers.

Results An improvement in understanding of assessing the mental capacity of the elderly was found. A better understanding of the laws system was found. A consensus on how to conducting a best interest meeting was reached.

Discussion The frontline healthcare workers are confused in assessing the mental capacity of the elderly and applying the laws principles in Hong Kong, continuous educations or laws reforms may be required.

Conclusion The clarity of Mental Capacity Act from UK may act as a guide for our future reforms.