The phrase "are not able to validate" is correct and usable in written English.
You can use it when discussing the inability to confirm or verify something, often in a technical or formal context.
Example: "Due to the missing documentation, we are not able to validate the authenticity of the claim."
Alternatives: "cannot confirm" or "are unable to verify."
This permits us to expect that the results produced by SIMPRO in functional mode are valid, although we are not able to validate the entire set of metrics measured by our simulator due to the unavailability of measurements performed with the same metrics by the CCVC authors.
Researchers are told stuff, but we are not able to validate it in a real way because nobody is making purchases.
Thus cloud users are not able to validate that the trusted services are behaving as expected, nor are they able to determine which cloud providers are the most trustworthy.
Although we are not able to validate this assumption using these data, evidence among the Kenyan Kipsigis has shown that current parental wealth was a reliable measure of the household wealth in which daughters grew up (Borgerhoff Mulder 1989).
Although we are not able to validate it due to the lack of DNA from the subject's parents, it raises a possibility that this variant could be a de novo mutation in this individual.
Finally, though we were not able to validate our models externally, we used the bootstrapping technique for validation that is considered as the preferred method for internal validation [ 40].
We were not able to validate or develop acceptable logistic mortality models or thresholds for C. nootkatensis or T. plicata.
The study was not able to validate the injuries recorded in the register with any other source of information (e.g. records of patients admitted to hospital) in the time available.
Due to rarity of CIS specimens, we were not able to validate up-regulation of gene expression directly.
Unfortunately, we were not able to validate this further due to the lack of good quality antibodies able to detect the MALT1-API2 protein.
For the main explanatory variables, we had to rely on an individual's response on physical and psychiatric illnesses and symptoms for lifetime and 12 months respectively, and we were not able to validate these self-reported diagnoses.
