Protecting Patient Privacy in Digital Health Systems

Digital systems make health data easier to use, and easier to misuse. Protecting patient privacy has to be designed in from the start, not added at the end.

Four practical principles

1. Collect only what you need. Data you never gather cannot leak.
2. Limit who can see what. Give each role the minimum access its work requires.
3. Protect data everywhere. That means in transit, at rest, and in backups.
4. Keep an audit trail. Know who accessed which record, and when.

Masking sensitive values

When data is shown in reports or logs, hide what readers don't need to see. A simple helper for phone numbers might look like this:

function maskPhone(phone: string): string {
  const hidden = Math.max(phone.length - 5, 0);
  return phone.slice(0, 3) + "*".repeat(hidden) + phone.slice(-2);
}

maskPhone("0911223344"); // "091*****44"

Privacy is not a feature to add later; it is part of the foundation.