Approximately 900,000 people or around three per cent of those eligible for a My Health Record have opted out of the system since July 16, a figure that is in line with expectations, the Australian Digital Health Agency says.

However, while awareness of the system and people's ability to opt out has grown in that period, a Senate inquiry into the MyHR has heard that four in 10 people are still unaware they will have a record created for them in two months.