What is the test for an order barring the testimony of a witness whose name was not revealed in answer to interrogatories?

The following factors have been held to support an order barring the testimony of a witness whose name was not revealed in answer to interrogatories requesting the names of all witnesses to an accident: (1) the answering party had willfully failed to reveal the witness' name; (2) the answer impeded the other party's trial preparation; (3) a continuance could not cure the defect; and (4) the answer did not go merely to evidence for which impeachment would be a remedy. (See Thoren v. Johnston & Washer, supra, 29 Cal.App.3d 270, 274-275, 105 Cal.Rptr. 276.)

In Campain v. Safeway Stores, Inc. (1972) 29 Cal.App.3d 362, 104 Cal.Rptr. 752, the failure of plaintiff to state at her deposition that she was damaged as to earnings or future earning capacity was held to bar her testimony as to such damages at trial. The appellate court reversed the trial court's ruling admitting her testimony because defendant had reasonably relied, to its prejudice, on the deposition answers in preparing for trial, and those had set at rest the issue of earnings. However, because a new trial could cure the defect, the appellate court ordered a new trial on the issue of damages.