As certain high school seniors work meticulously this month to finish their early applications to colleges, some may not realize that comments they casually make online could negatively affect their prospects.

“Students’ social media and digital footprint can sometimes play a role in the admissions process,”

Each official told me that it was not routine practice at his or her institution for admissions officers to use Google searches on applicants or to peruse their social media posts. Most said their school received so many applications to review — with essays, recommendations and, often, supplemental portfolios — that staff members wouldn’t be able to do extra research online. A few also felt that online investigations might lead to unfair or inconsistent treatment.