The phrase 'whether they require' is correct and usable in written English.
You can use it when you want to express uncertainty about the need or necessity for something. For example: We must carefully consider whether they require additional resources before allocating funds.
The key issue is that interactions and risks should be systematically assessed and explicit decisions made about whether they require discussion in a guideline, similar to the requirement for treatment benefits to be systematically and explicitly assessed.
Quarterly earnings should be analyzed only to determine whether they require any change to a stock's future valuation.
A recurring debate is whether large carnivores can be conserved in human used landscapes (land sharing) or whether they require specially designated areas (land sparing).
Further studies are needed to explore the differences between ILC molecular subtypes and to determine whether they require different therapeutic strategies.
Van Gaal may have asked United for at least the third time following Saturday's home defeat to Southampton whether they require him to walk away.
Because of ambiguities in state law, local groundwater authorities differ in whether they require companies to get permits for water wells drilled to supply frackers.
The psychologists asked students to respond to e-mail messages that were similar but differed in whether they required abstract or concrete thinking.
The court ruled against the government; it said that passport rules, whether they required consent from a married person's partner or not, should apply equally to men and women.
White became acquainted with Gustav Schmoeller, Rector of Berlin University, and sent inquiries to many American universities for him to ascertain whether they required Latin and Greek from candidates for the B.A. degree.
The only reasons to prefer a screening approach is if deworming drugs had negative effects on uninfected children (they do not), or if the costs of treating uninfected children in a mass campaign were greater than the costs of individually testing children to determine whether they required treatment (in fact it is much cheaper to mass treat than to diagnose and treat).
It asks whether workers "struggle[d] with the demanding working conditions," and whether they required public assistance.
