The recent hack into the database of the nation's largest healthcare group was a rude awakening and a vindication of the concern by many medical professionals about the sharing of what most would consider very private and personal information on a centralised database (Info on 1.5m SingHealth patients stolen in worst cyber attack; July 21).

Despite objections from the ground, the decision to get healthcare institutions to contribute data to a national health database, or the National Electronic Health Record, went ahead, with limits for doctors to have access to only their patients' data.

Unfortunately, there is no privacy setting when it comes to hackers.

People's reputations can be ruined when intimate details of their private lives get leaked out: online shaming of those diagnosed with sexually transmitted diseases, blackmailing the chief executive with early-stage dementia, to name some examples.

The sharing of medical information is important and helpful for doctors, but many people would rather limit access to sensitive information about themselves to as few people as possible.

Hackers and cyber-security teams are in a constant race for the upper hand. Centralised data serves as a huge honeypot for malicious individuals to try their hand at cracking a system. The National Health Servicein Britain, a country with advanced cyber capabilities, succumbed to this not too long ago, triggering a flood of concerns from doctors here.

The law to share all medical information may have been put on hold for now, but it will come into effect sooner or later. Knowing that we can never be 100 per cent sure about security, we should tweak the law to be a bit more accommodating.

By all means share information, but allow patients the choice of which pieces of information they do not wish to upload onto a central database.

Should patients one day choose not to share information with their doctors for fear of it going into the public domain, that will, ironically, be the day that the push for big data has failed us.

Peter Chen