The phrase "subtle factors" is correct and usable in written English.
You can use the phrase when referring to small or difficult to define details that may impact a situation or outcome. For example, "The success of the project was influenced by a number of subtle factors, including the timing of the presentation and the reactions of key stakeholders."
Still, even more subtle factors may be at play.
More subtle factors also contributed to this outbreak.
So researchers have begun exploring more subtle factors, like crime, pollution and family support.
We respond to emotional cues and pheromones and all sorts of subtle factors.
Before prescribing pharmaceuticals, doctors must consider the benefits and risks for each patient, sometimes based on subtle factors in that individual's physiology or health profile.
The obvious reason for this is stereotyping on the part of white people in power, say many sports sociologists, but there could also be more subtle factors.
But in two days of interviews here and north of the Ohio River in Cincinnati, most young people acknowledged — or even insisted — that race was still a powerful if subtle factor among their peers.
Some observers attribute this discrepancy to overt discrimination, others to subtler factors, like an adversarial office culture or hours that eat away at family time.
But Eisinger homes in on a subtler factor: the professional psychology of élite federal prosecutors.
In light of this finding, evaluation of whether any KT strategy achieves its knowledge translation goal (e.g., build awareness, share knowledge, impact policy, change behavior or practice) and the subtle contextual factors that facilitate or hinder this outcome, is an essential component of the KT process, and is lacking in our current state of KT practice and science.
Beyond abstraction and imagery are subtle formal factors like circular compositions and meandering, interconnecting lines.
