The phrase "allowed to confirm" is correct and usable in written English.
You could use it to indicate that someone or something has been given authorization to verify or identify something. For example, "The police were allowed to confirm that the suspect was the one who committed the crime."
I am not allowed to confirm if the [surgery] has been done or not".
The combination with pressure measurement allowed to confirm that pressure peaks are achieved in correspondence of the water front.
"For the consumer in, say, Germany, this might represent hacking of their data by an Irish business on behalf of the UK state under a bulk warrant – activity which the provider is not even allowed to confirm or deny.
Management at the five-star hotel said they were not allowed to confirm or deny that the group had checked in or that their hotel was part of the investigation.
The experimental investigation performed in this paper allowed to confirm some theoretical hypotheses, such as that of considering the Keulegan Carpenter number (KC) as the key parameter which controls the phenomenon, to be confirmed.
Impedance measurements allowed to confirm the formation of insulating material and to estimate the dielectric constant of the oxides, which resulted to be monotonically increasing with increasing Ta content (from 9 for pure Al2O3 to 30 for pure Ta2O5).
Further observations of nine inconclusive systems (including seven NIQs) will allow to confirm (or not) their gravitational lens nature.
The presented experimental results allow to confirm the validity of the proposed FPAA based architecture.
Complementary structural investigation allows to confirm the influence of the component content in the glass composition revealed by the model.
The extended model allows to confirm some, but not all, assumptions commonly associated with point defect and mixed conduction type models.
Further experiments will allow to confirm or reject this hypothesis.
