OBJECTIVES Tight glycemic control of diabetic patients yields both clinical and financial benefits. Despite recommendations for HbA1C testing to assess the effectiveness of management plans on glycemic control, achieving adherence to recommendations for frequency of HbA1C testing continues to be a challenge. When prior authorization (PA) was required in the Leumit Health Fund of Israel for expensive diabetes medications, requests for these drugs were not reviewed until the patient had performed an HbA1C test (one test within the previous four months). This policy induced complete adherence to recommendations for testing amongst patients treated with target drugs. The purpose of this study was to ascertain whether revocation of the PA requirement resulted in inferior rates of HbA1C testing amongst new users of these drugs. METHODS Data on of new users of the target drugs and on HbA1C testing in these patients was extracted from EPR databases for the six-month post-revocation period. The proportion of patients who performed at least one HbA1C test during the four months prior to initiation of treatment and 95% confidence intervals were calculated. The data were stratified by month to detect possible trends in rates of testing during the post policy-change period. RESULTS After rescinding the PA requirement, HbA1C testing amongst incident users of the target drugs dropped from 100% during the PA period to rates of 85.6% (95% CI= 79.7, 91.5) to 94.4% (95% CI= 90.8, 97.9). Statistically significant variance in monthly rates of testing was not observed. CONCLUSIONS The PA requirement resulted in total performance of a lab test necessary to monitor drug-therapy outcomes in diabetic patients. When PA is implemented as a quality-assurance strategy, revocation should be accompanied by continuing-education efforts to maintain adherence to recommendations for appropriate care.