The phrase "a valid substitute for" is correct and usable in written English.
It can be used when discussing alternatives or replacements for something, indicating that one option can effectively replace another.
Example: "In this recipe, applesauce can be a valid substitute for oil, providing moisture without the added fat."
Alternatives: "an acceptable replacement for" or "a legitimate alternative to".
Therefore the use of sheep suppressively treated with effective anthelmintics appears to be a valid substitute for gastrointestinal nematode-free lambs in field experiments.
In a six-page decision rejecting a request from alternative schools for exemption from the Regents exams, Mr. Mills said that the schools could not be excused because advocates had failed to present evidence that portfolios were a valid substitute for the test.
When David Cameron set up the National Citizen Service along with his "big society" initiative in 2011, there was no indication that the NCS would eventually siphon off youth service budgets: this four-week summer citizenship scheme cannot be considered a valid substitute for year-round youth provision.
In the past few years, collagen matrices (CM) have been studied as a valid substitute for free gingival grafts, in particular the porcine CM Mucograft (Geistlich Biomaterials GmbH, Baden-Baden, Germany).
This study reported that oral fluid was a valid substitute for serum sampling for patients on chronic oral morphine therapy.
Two Norwegian studies have shown that CDR staging is a valid substitute for a dementia assessment among nursing-home patients to rate dementia and dementia severity [ 60, 61].
It's apparently a very old idea going back thousands of years, and we know that in pseudoscience circles age is a perfectly valid substitute for "evidence that is actually works".
However, for healthcare researchers around the world who did not have a readymade CMI at hand, the search for a valid substitute has always been a painstaking process.
We believe the use of OSR DNA to be a valid substitute since none of the primer sequences for either assay will be present in non-transgenic soya or oilseed rape.
Displacement interactions were as frequent as aggressive interactions, seemed to be most reliable for computing hierarchy parameters and constitute a valid substitute to decided aggressive interactions to build hierarchies.
This was again important for simplification of future protocols as arterial cannulation could be omitted if venous sampling was proven to be a valid substitute.
