Effects of the new diagnosis-related group-based payment system and the increased incentive policy rates on the utilization rate of diagnostic laboratory test in Korea

A new diagnosis-related group (DRG) based payment system has been implemented in most public hospitals in Korea. We investigated the effects of the new DRG system and its incentive policy on the utilization rate of diagnostic laboratory tests. Three groups were categorized; 36 hospitals under the new DRG system (participant group), 72 hospitals (control-1) matching with 36 participants according to the number of beds, and 42 tertiary hospitals (control-2). The patients of acute myocardial infarction, cerebral infarction, type 2 diabetes mellitus, and gonarthrosis receiving total arthroplasty were included. We analyzed the mean length of stay and the number of diagnostic laboratory tests conducted during hospitalization of the three groups according to the new DRG system and the incentive policy rates under the new DRG system. Before participating in the new DRG system, the number of diagnostic laboratory tests in the participant group was less than that in the two control groups for all four diseases. However, although the participant group’s length of stay decreased under the new DRG system, the number of diagnostic laboratory tests increased as the maximum incentive policy rate increased. The increment of the number of diagnostic laboratory tests was prominent in the period of a maximum of 35% incentive policy rates. Finally, the number of diagnostic laboratory tests of the participant group was similar to or exceeded that of the control-2 group. The new DRG system’s incentive policy rates played a driving force on the increased utilization rate of the diagnostic laboratory test. For preparing in advance for the change in incentive policy rates, monitoring and guidelines for the utilization of diagnostic laboratory tests are necessary.

The Utility of the Cl:PO4 Ratio in Patients With Variant Versions of Primary Hyperparathyroidism

Objective To determine the significance and impact of additional chloride testing as part of a diagnostic laboratory test battery for borderline primary hyperparathyroidism (pHPT). Study Design Retrospective database review of parathyroidectomy patients. Setting A tertiary care, academic health sciences center. Subjects and Methods Patients referred to a head and neck endocrine clinic for evaluation and treatment for pHPT. Results After exclusions, there were a total of 226 patients who underwent parathyroidectomy for primary hyperparathyroidism with the requisite preoperative and postoperative labs. Seventy-seven additional patients who had a thyroid operation for a nonmalignant cause were included as controls. Of the 303 total patients, 166 had normal calcium levels (<10.4 mg/dL), and 54 (32.5%) also exhibited hyperchloremia (>106 mmol/L). Of the 47 patients with normal calcium and parathyroid hormone (PTH) levels (<88 pg/mL), 6 (12.8%) had hyperchloremia, and of the 118 patients with normocalcemic pHPT, 48 (40.7%) were hyperchloremic. The area under the curve for the Cl:PO4 was 0.712. When using a cutoff of 33, the reported sensitivity and specificity of the curve were 58.4% and 28.6%, respectively. Conclusion The Cl:PO4 ratio was a moderately sensitive test for the diagnosis of the borderline variants of primary hyperparathyroidism. The Ca:PO4 ratio was superior to the Cl:PO4 ratio. Our data also showed the superiority of preoperative calcium and ionized calcium over PTH when predicting the presence of pHPT.

Methodology in Diagnostic Laboratory Test Research in Clinical Chemistry and Clinical Chemistry and Laboratory Medicine

Background: The application of epidemiologic principles to clinical diagnosis has been less developed than in other clinical areas. Knowledge of the main flaws affecting diagnostic laboratory test research is the first step for improving its quality. We assessed the methodologic aspects of articles on laboratory tests. Methods: We included articles that estimated indexes of diagnostic accuracy (sensitivity and specificity) and were published in Clinical Chemistry or Clinical Chemistry and Laboratory Medicine in 1996, 2001, and 2002. Clinical Chemistry has paid special attention to this field of research since 1996 by publishing recommendations, checklists, and reviews. Articles were identified through electronic searches in Medline. The strategy combined the Mesh term “sensitivity and specificity” (exploded) with the text words “specificity”, “false negative”, and “accuracy”. We examined adherence to seven methodologic criteria used in the study by Reid et al. (JAMA1995;274:645–51) of papers published in general medical journals. Three observers evaluated each article independently. Results: Seventy-nine articles fulfilled the inclusion criteria. The percentage of studies that satisfied each criterion improved from 1996 to 2002. Substantial improvement was observed in reporting of the statistical uncertainty of indices of diagnostic accuracy, in criteria based on clinical information from the study population (spectrum composition), and in avoidance of workup bias. Analytical reproducibility was reported frequently (68%), whereas information about indeterminate results was rarely provided. The mean number of methodologic criteria satisfied showed a statistically significant increase over the 3 years in Clinical Chemistry but not in Clinical Chemistry and Laboratory Medicine. Conclusions: The methodologic quality of the articles on diagnostic test research published in Clinical Chemistry and Clinical Chemistry and Laboratory Medicine is comparable to the quality observed in the best general medical journals. The methodologic aspects that most need improvement are those linked to the clinical information of the populations studied. Editorial actions aimed to increase the quality of reporting of diagnostic studies could have a relevant positive effect, as shown by the improvement observed in Clinical Chemistry.

Polymyalgia rheumatica

Polymyalgia rheumatica and temporal arteritis represent opposite poles of a single disease spectrum. In the former, girdle stiffness predominates; in the latter, frank vasculitis is demonstrable. There is no diagnostic laboratory test for polymyalgia rheumatica, and earlier reviews in 1993 and 1998 in this journal both drew attention to the difficulty in diagnosing polymyalgia rheumatica, particularly in the elderly.