The phrase "affect the proportion of" is correct and usable in written English.
It can be used when discussing how one variable influences the ratio or distribution of another variable.
Example: "Changes in temperature can significantly affect the proportion of dissolved oxygen in water."
Alternatives: "influence the ratio of" or "impact the distribution of".
Delaying nest box access by 15 weeks did not significantly affect the proportion of eggs laid in nest boxes rather than on the floor (P = 0.40).
Based on survival analysis, although the rate at which cows were inseminated differed among treatments, treatment did not affect the proportion of cows pregnant by 300 DIM.
The day on which letrozole treatment was initiated did not affect the proportion of heifers that ovulated or the interval to ovulation.
We addressed two main questions: 1) does fire frequency affect the proportion of reproducing individuals and the intensity of each flowering and fruiting event?; and 2) does fire frequency influence the reproductive synchrony of species across the landscape?
In experiment 1, there was a tendency for the presynchronization protocol to affect the proportion of heifers ovulating in response to the first GnRH injection of the Cosynch + CIDR protocol.
The Dispatcher-Assisted Randomized Trial (DART) was designed to compare 2 types of dispatcher cardiopulmonary (CPR) instruction, but not intended to affect the proportion of arrest victims that received bystander CPR.
The BMJ already asks authors to declare "competing interests" and may soon shift to asking for "relevant interests", because its editors have found that such changes in terminology affect the proportion of people who own up quite significantly.
Birth rates and death rates, as they vary in time and place, necessarily affect the proportion of the population available to the different European countries for the economy and the armed forces.
The chemistry and pore structure of various types of column packing materials and of the salt additives to the mobile phase affect the proportion of the pore volume non-accessible to anions due to ion-exclusion and consequently the peak asymmetry and hydrophobic selectivity in reversed-phase chromatography of organic acids.
However, it is noteworthy that the activation threshold will not affect the proportion of resource saving.
"No H-1B visa policy will affect the proportion of students going into IT [information technology] fields.
