— Order, Supreme Court, New York County, entered September 7, 1978, which modified the arbitrator’s award from $3,000, to $7,307.60, plus statutory interest, modified, on the law, without costs and disbursements, to the extent of remanding to the arbitrator for consideration of possible error in calculation, and otherwise aifirmed. In compulsory arbitration the test on review is "whether the award is supported by evidence or other basis in reason, as may be appropriate, and appearing in the record.” (Mount St. Mary’s Hosp. v Catherwood, 26 NY2d 493, 508.) This concept was expanded in Caso v Coffey (41 NY2d 153, 158) as follows: "An award may be found on review to be rational if any basis for such a conclusion is apparent to the court * * * it need only appear from the decision of the arbitrators that the criteria specified in the statute were 'considered’ in good faith and that the resulting award has a 'plausible basis’ ”. We cannot tell from the record the basis used by the arbitrator in reducing petitioner-respondent’s uncontested medical bills from $7,307.60 to $3,000. (See Insurance Law, § 671.) Concur— Kupferman, J. P., Birns and Ross, JJ.