The phrase "can be questionable" is correct and usable in written English.
It can be used when discussing something that may lack clarity, reliability, or certainty.
Example: "The validity of the research findings can be questionable, given the small sample size."
Alternatives: "may be dubious" or "could be uncertain."
Safety standards can be questionable.
Character interactions can be questionable.
Although many Americans report using them, their benefits can be questionable.
(Mr. McAnuff's visual taste can be questionable, as anyone who saw his overdesigned "Guys and Dolls" on Broadway might attest).
In my line of work, the quality of data can be questionable and a lot of information simply can't be taken at face value.
And, as in the case of Anne Glover, the chief scientist who was eased out, the motivations for some of its decisions can be questionable.
The quality of service can also be questionable.
Our correspondent says that safety protocols are often not observed at worksites in Vietnam, and the quality of construction materials can also be questionable.
As estimates from establishment surveys are usually over- or under-estimated, when compared with observations from tour-based surveys, Allen et al. [17] proposed asking for dwell time estimates according to vehicle type, as a way to increase precision, even though estimates' accuracy can still be questionable.
Data quality on causes of death is greater when obtained from hospital charts in comparison when obtained via death certificates of deaths occurring outside the hospital context, in which the nature of the cause of death can often be questionable.
How far this can be taken is questionable when even the nominations themselves resulted in snubs to some of the most streamed artists, such as Taylor Swift, whose best-selling Reputation was overlooked as a potential Album Of The Year.
