The phrase "complex disease" is correct and usable in written English.
For example, you might use it in a sentence such as "Doctors are still trying to understand the complexities of the disease."
Cancer is a complex disease.
"But this is a complex disease.
"For anybody else, it is a complex disease," she says.
Still, perhaps this was the first sign of this complex disease.
Alzheimer's is an extremely complex disease that clearly involves a combination of environmental and genetic factors.
For example, many clinical trials exclude people with a complex disease or with multiple medical conditions.
Ultimately, we want to apply these techniques to important real-world problems like climate modelling or complex disease analysis, right?
Geneticists regard schizophrenia as a complex disease, meaning one to which many different mutated genes are thought to contribute.
Cancer is a complex disease, arising from the interaction of our genes with numerous factors in the environment.
"People have volunteered to participate anonymously in studies which explain some of the genetic explanations of common complex disease".
"Asthma is a complex disease, and any intervention aimed at the whole population will be potentially dangerous".
