The phrase "discern the effect of" is correct and usable in written English.
You can use it to indicate that something is being examined in order to determine the consequences, results, or impacts it may have. For example: "We must discern the effect of the new tax law on our business operations before we make any decisions."
This enables us to discern the effect of the clearing mechanism from the effect of the overnight trading halt.
It also means it is impossible to discern the effect of the tougher regime on the falling number of jobseeker's allowance (JSA) claimants.
Using broad-tuned ligands allowed us to discern the effect of bitter tastants on multiple features of asthma pathogenesis in mice.
To discern the effect of modern human activity on the loss of species requires determining how fast species disappeared in the absence of that activity.
To discern the effect of unsteady aerodynamics on road vehicle stability, large eddy simulation has been conducted to simulate the flow past simplified vehicle models.
A 2007 study by researchers at MIT and at another Washington think tank, the Brookings Institution, did find some benefits when it attempted to discern the effect of increased broadband penetration on job opportunities at a state level.
Using RT therefore seems to be an effective and promising strategy to better discern the effects of the room acoustics and to enhance the acoustical design of rooms for speech.
Three cohorts moved through these modules in different orders, allowing us to discern the effects of a specific training module and compare it to the other modules.
At Harris Farms in California's Central Valley, it is not difficult to discern the effects of the state's continuing drought.
Compared to my own studies, experiments like those designed to discern the effects of age and alcohol on laughter were captivating (both concluded that the more you drink/age, the less you understand, but the more you laugh).
Another large camera, known as the Dark Energy Survey, will swing into action at a mountaintop observatory in Chile, looking to discern the effects of dark energy on the history and evolution of the universe.
