It can also be difficult to establish cause and effect.

Major studies have been conducted in an effort to establish the cause of death.

The police have not yet been able to establish the cause of death for a man who was found floating in the river.

The experts were unable to establish the cause of death.

Because the study looked at correlations, it could not establish cause and effect.

A police investigation has been initiated to establish the cause of her death.

She added that the medical examiner's office may not be able to establish the cause of death for a few weeks.

"But it's hard to establish cause and effect," she said.

Their answers as to why they made this choice does not allow to establish the actual cause.

An autopsy was ordered to establish the cause of death.