Corp. of Mercer Univ. v. Nat. Gypsum Co., 258 Ga. 365, 366(1) ( 368 S.E.2d 732) (1994); Hanna v. McWilliams, 213 Ga. App. 648 ( 446 S.E.2d 741) (1994). At the same time, however, a cause of action in negligence accrues and the statute of limitation begins to run when there is a negligent act coupled with a proximately resulting injury. U-Haul Co. c. v. Abreu Robeson, Inc., 247 Ga. 565, 566 ( 227 S.E.2d 497) (1981). The true test to determine when a cause of action accrues is to ascertain the time when the plaintiff could first have maintained her action to a successful result.