The phrase "affect the extent of" is correct and usable in written English.
It can be used when discussing how one factor influences the degree or range of another factor.
Example: "The new policy will affect the extent of employee engagement within the organization."
Alternatives: "influence the degree of" or "impact the range of".
Educational differences between speakers strongly affect the extent of their vocabulary.
Both concentration and the molecular structure of the additives affect the extent of these alterations.
Processing conditions, specifically the solvent concentration, strongly affect the extent of primary cyclization.
Neither temporary shortage of capacity nor geographical dispersion of activities seem to affect the extent of subcontracting.
As an uninhabitable rock, it does not affect the extent of UK's territorial waters (which extends 200 nautical miles from St Kilda and so embraces Rockall) or its continental shelf.
Care was exercised to achieve precision in strain-rate control in these tests since strain-rate and temperature history do affect the extent of cavitation.
The state of mixing in a continuous flow vessel is shown to affect the extent of aggregation and the extent of aggregation at which mathematical gelation occurs.
Residual stress in ductile thin films is shown to significantly affect the extent of film plasticity and interfacial fracture energy during debonding in thin-film structures.
Interestingly, the factors that affect the extent of use of technological innovations do also affect that of clusters of management practices.
Nitrogen species survived in the first layer reaction were found to strongly affect the extent of desulfurization in the subsequent second layer reaction.
Ce additions were also found to reduce the oxidation rate and affect the extent of voids at the scale alloy interface.
