The phrase "are causes of" is correct and usable in written English.
It can be used when discussing factors or elements that contribute to a particular outcome or effect.
Example: "The researchers found that several environmental factors are causes of climate change."
Alternatives: "contribute to" or "factors leading to".
Immobilization and space flight are causes of disuse osteoporosis.
Its size, demands, ambitions, and expense are causes of, rather than cures for, incompetence.
The lawyer, Charles W. Gittins, has said communications problems and poor command decisions are causes of many such Air Force accidents, including that of his client, Maj.
Organisational change, dealing with violent and unpredictable patients and experiencing harrowing and traumatic situations are causes of stress for staff, NHS Employers says.
The personal tragedies, in Mr. Ricketts's view, made Kipling "a sadder and a harder man" and are causes of the dark bluster that came in his later years.
It isn't enough for them to know in the abstract that sub-personal biases and epistemic vices are causes of diagnostic error.
Spontaneity and chance are causes of effects which though they might result from intelligence or nature, have in fact been caused by something incidentally.
Economists differ on the extent to which they think business and consumer confidence are causes of, rather than symptoms of, poor economic performance.
In health terms, red meat is strongly linked with bowel cancer, while meat and dairy products high in saturated fat are causes of obesity and heart disease.
Soldiers' welfare is neglected: poor food and lack of leave are causes of the high incidence of desertions and absences without leave.
Outsized executive pay, or a hedge-fund manager's billion-dollar year, are causes of inequality but also part of everything: how employees are trained, how college classes are taught, what books we read, how we design our homes.
