The report, released to The Courier this week, reveals Matthew Ruff, 34, died from multiple injuries after the vehicle he was driving hit the bus on the Midland Highway near Sulky in June last year.

While the report does not establish blame or a definitive cause for the accident, it has investigated contributing factors, such as Mr Ruff's condition and the state of the car involved.

Two witnesses reported they saw Mr Ruff's car drift toward the centre of the road - one saw his car making "steady and not quick and jerky" movements, after pulling onto the highway without indicating before it reached Creswick and turned left towards Ballarat.

READ MORE:

A second, who saw the collision, was driving north behind the bus at the time, and saw Mr Ruff's car, travelling south, cross the centre line, before the bus moved to the right to avoid hitting the car.

The bus driver could only recall the blur of a motor vehicle in front to the left of his bus, and the noise of the impact - the bus then hit an embankment.

The point of impact was in the north-bound lane, about 1.94 metres in from the outside white line.

No skid marks were found prior to the point of impact from Mr Ruff's car.

The report notes Mr Ruff had been cutting firewood with friend the day before, and was still awake about 1.30am watching television.

He spoke to his mother on the telephone about 1.30pm on the day of the accident.

A toxicology analysis mentions the presence of amphetamine and methamphetamine in Mr Ruff's body, and forensic pathologist Clinical Professor David Ranson commented in the report "the contribution of amphetamine-like drugs to the circumstances of the death should be considered in relation to the behavioural factors that (the) class of drug can lead to".

The Victoria Police coronial investigation, begun on the day of the accident last year, found the road was slightly damp, traffic was light, and visibility was average.

The section of road was a straight single lane carriageway with double lines.

An examination of the car found that the driver's side front seat belt was "in the retracted position and showed no damage or 'scuffing'".

The Mechanical Investigation Unit did not consider that Mr Ruff was wearing a seat belt, as significant 'scuffing' would be expected to be present.

The Coroner expressed her sincere condolences to Mr Ruff's family.

Have you signed up to The Courier's variety of news emails? You can register below and make sure you are up to date with everything that's happening in Ballarat.