Do we know what inappropriate laboratory utilization is? A systematic review of laboratory clinical audits

OBJECTIVE: Laboratory utilization has steadily increased, and some studies suggest inappropriate utilization. Therefore, we wished to assess studies that measure inappropriate laboratory use in light of methodological criteria. DESIGN: Systematic review of published studies. DATA SOURCES: MEDLINE, HEALTHSTAR, and EMBASE databases were searched from 1966 to September 1997 using a broad and inclusive strategy with no language restriction. In addition, the references of all retrieved studies and 3 textbooks on diagnostic testing were hand-searched. STUDY SELECTION: All studies that provided and applied criteria for inappropriate laboratory use. DATA EXTRACTION: Studies were categorized based on whether the criteria were implicit (objective criteria for inappropriate utilization not provided or very broad) or explicit. Guidelines for evaluation were applied to each study by a single reviewer. DATA SYNTHESIS: Forty-four eligible studies were identified. Eleven studies used implicit criteria for inappropriate laboratory utilization and contained small numbers of patients or physicians. Most did not adequately assess the reliability of the implicit criteria. Thirty-three studies used explicit criteria based on the appropriateness of test choice, frequency, and timing, as well as the probability of a positive result. There were large variations in the estimates of inappropriate laboratory use (4.5%-95%). Evidence supporting the explicit criteria was frequently weak by the standards suggested for therapeutic maneuvers, but was nonetheless compelling based on principles of physiology, pharmacology, and probability. CONCLUSIONS: Many studies identify inappropriate laboratory use based on implicit or explicit criteria that do not meet methodological standards suggested for audits of therapeutic maneuvers. Researchers should develop alternative evidentiary standards for measuring inappropriateness of laboratory test use.     

Pore, surface and fillet moisture in centrifuged beds of coarse coal

The moisture content of the coarse coking coal product from the centrifuges of preparation plants was investigated to evaluate the contribution of three types of water: that held internally in pores, that in fillets at points of contacts between the particles, and the moisture covering the surface. A standardised laboratory centrifuge test was used to measure the total non-centrifugable moisture (NCM) content and also the quantity held in internal pores, called NCM_i. The fillet moisture NCM_f was estimated by means of a formulation which relies on experimentally measured holdup volumes, supplemented by a physical model. The surface moisture NCM_s could then be derived by difference. The NCM_f, which depends on the body force, the particle size and the surface tension and contact angle of the liquid, ranges from effectively zero for large particles to 10% for fines. The surface moisture NCM_s is of the order of 0.5% for high rank coals and increases to 1.5% for lower rank coals.     

3H]paroxetine binding is altered in the hippocampus but not the frontal cortex or caudate nucleus from subjects with schizophrenia

[3H]Paroxetine binding to particulate membrane from tissue, obtained at autopsy, from the hippocampus, frontal cortex, and caudate nucleus from subjects who had or had not had schizophrenia was measured. The density of [3H]paroxetine binding to membranes from subjects who had or had not had schizophrenia did not differ. Similarly, the affinity of [3H]paroxetine binding in the frontal cortex and caudate nucleus was not different. By contrast, the affinity of [3H]paroxetine binding to hippocampal membrane from subjects who had schizophrenia was significantly lower than the affinity of binding for the nonschizophrenic subjects (0.40 +/- 0.06 vs. 0.26 +/- 0.02; p < 0.05). As [3H]paroxetine binds to the serotonin transporter, these data suggest that the serotonin transporter is altered in the hippocampus in subjects with schizophrenia.     

Pharmacologic atrial natriuretic peptide reduces human leg capillary filtration

Atrial natriuretic peptide (ANP) is produced and secreted by atrial cells. We measured calf capillary filtration rate with prolonged venous-occlusion plethysmography of supine healthy male subjects during pharmacologic infusion of ANP (48 pmol/kg/min for 15 min; n = 6) and during placebo infusion (n = 7). Results during infusions were compared to prior control measurements. ANP infusion increased plasma [ANP] from 30 +/- 4 to 2,568 +/- 595 pmol/l. Systemic hemoconcentration occurred during ANP infusion: mean hematocrit and plasma colloid osmotic pressure increased 4.6 and 11.3%, respectively, relative to preinfusion baseline values (p < 0.05). Mean calf filtration, however, was significantly reduced from 0.15 to 0.08 ml/100 ml/min with ANP. Heart rate increased 20% with ANP infusion, whereas blood pressure was unchanged. Calf conductance (blood flow/arterial pressure) and venous compliance were unaffected by ANP infusion. Placebo infusion had no effect relative to prior baseline control measurements. Although ANP induced systemic capillary filtration, in the calf, filtration was reduced with ANP. Therefore, pharmacologic ANP infusion enhances capillary filtration from the systemic circulation, perhaps at upper body or splanchnic sites or both, while having the opposite effect in the leg.     

Sudden death in sheep associated with Clostridium sordellii

Clostridium sordellii was isolated from 37 sheep, in 29 flocks, which died suddenly between 1993 and 1995. The sheep were of all ages, but the most severe gross lesions affected lambs four to 10 weeks of age. In older weaned lambs and ewes the gross changes were less marked and more variable. Thirty sheep suffering from a variety of other conditions were examined and C sordellii was not isolated. The isolation of C sordellii has been reported only twice before from sheep in Britain, and on both occasions no detailed investigations were described. The evidence from this study indicates that C sordellii should be considered when investigating the cause of sudden death in sheep of all ages in Britain.     

Transphyseal vessel involvement in repair of metaphyseal retained cartilage

A foal with retained cartilage in the distal metaphysis of the right and left radii and third metacarpal bones had abnormal physeal vasculature. In areas where cartilage was retained, vessels crossed the physis, and branched at the physeal-metaphyseal junction or at the site of retained cartilage. Vessels appeared to be involved in re-initiation of endochondral ossification and in the repair reponse to the presence of retained cartilage. In areas where the physis was radiographically and histologically normal, no vessels crossed the physis. A function of transphyseal vessels may be as a reserve blood supply in areas of metaphyseal abnormality, at a stage of maturity when metaphyseal vessels are not well developed.     

A framework for analysis of data quality research

Organizational databases are pervaded with data of poor quality. However, there has not been an analysis of the data quality literature that provides an overall understanding of the state-of-art research in this area. Using an analogy between product manufacturing and data manufacturing, this paper develops a framework for analyzing data quality research, and uses it as the basis for organizing the data quality literature. This framework consists of seven elements: management responsibilities, operation and assurance costs, research and development, production, distribution, personnel management, and legal function. The analysis reveals that most research efforts focus on operation and assurance costs, research and development, and production of data products. Unexplored research topics and unresolved issues are identified and directions for future research provided