~のではないかと (I fear/think that)

A hedging frame [clause] + (の)ではないかと + [verb of thinking/fearing/worrying], literally 'thinking/fearing isn't it the case that X?' Used to softly express worry, tentative opinion, or guess. The の may be dropped after a noun predicate (腱鞘炎ではないかと思う) or kept for verb/adjective predicates (断るのではないかと心配する).