OBJECTIVE: To examine the precision and completeness of information in medical records for evaluating the appropriateness of operative indications for lumbar disc surgery. DESIGN: Retrospective review of records. SETTING: University department of neurosurgery, Switzerland. SUBJECT: 100 patients. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Proportion of pre-defined, detailed appropriateness criteria present in the records. Proportion of cases that could unequivocally be classified as to the appropriateness of the indication for operation. RESULTS: The criteria were present and precise for 52 of the items (range 9-90); present but imprecise for 38 of the items, and absent for 10. Because of this imprecision, the appropriateness of only 7 of the operative indications could be unequivocally assessed retrospectively. CONCLUSION: Medical records are of limited use in assessing the appropriate management of care. The process of care should therefore be evaluated prospectively.