Evaluation of techniques for the presentation of laboratory data: support of pattern recognition.

Two tabular and two graphical techniques for the presentation of laboratory test results were compared in a reaction-time experiment with 22 volunteers. The experimental setup was designed to determine whether one or more of the presentation techniques facilitated the recognition of four predefined combinations of abnormal test results. Using a conventional, tabular presentation technique as a reference, faster median response times were obtained with each of the other three presentation techniques, irrespective of pattern.

Evaluation of techniques for the presentation of laboratory data. II: Accuracy of interpretation.

Four tabular and two graphical techniques for the presentation of laboratory test results were evaluated in a reaction time experiment with 25 volunteers. Artificial variables and values were used to represent sets of 12 laboratory tests to eliminate the possible effects of clinical experience. Analyses focused on four types of errors in interpretation.

Evaluation of techniques for the presentation of laboratory data. I: Time needed for interpretation.

Four tabular and two graphical techniques for the presentation of laboratory test results were evaluated in a reaction-time experiment with 25 volunteers. Artificial variables and values were used to represent sets of 12 laboratory tests to eliminate the possible effects of clinical experience. Analyses focused on reaction times for correctly classified sets of data.

Graphical non-linear representation of multi-dimensional laboratory measurements in their clinical context.

A polygon-based graphical representation of laboratory test results using nonlinear scaling is described. It is argued that the nonlinearity of the scale and the use of colors in the representation facilitates interpretation of the test result in its relationship to the standard reference range and critical clinical decision levels. Preliminary results suggest that this representation may be fruitfully used to enhance the efficiency of the information transfer from the clinical chemistry laboratory to clinicians.

A three-parameter Langmuir-type model for fitting standard curves of sandwich enzyme immunoassays with special attention to the alpha-fetoprotein assay.

In a simplified approach to the reaction kinetics of enzyme-linked immunoassays, a Langmuir-type equation y = [ax/(b + x)] + c was derived. This model proved to be superior to logit-log and semilog models in the curve-fitting of standard curves. An assay for alpha-fetoprotein developed in our laboratory with a sensitivity of 2 g/liter and a between-day coefficient of variation of about 15% was used for comparison of the different models.

Comparison of three different assay procedures for the determination of HbA1 with special attention to the influence of pre-HbA1c, temperature and haemoglobin concentration.

Three different methods for the measurement of glycated haemoglobin or HbA1, based on agar gel electrophoresis, ion-exchange and affinity chromatography were compared. All three showed acceptable precision (overall CV being less than 5%) and correlated well with each other (r greater than 0.945).

Effects of furosemide on biliary secretion, pancreatic blood flow, and pancreatic exocrine secretion.

The effects of furosemide on biliary secretion and on pancreatic hemodynamics and exocrine function were studied by quantitative flowmetry and timed collections of biliary and pancreatic exocrine secretion in the anesthetized dog. Biliary flow and the output of its components (Na+, K+, Ca, Mg, 3-OH bile salts, and bilirubin) increased significantly following a furosemide injection of 0.6 mg/kg and rose progressively to 75-150 per cent above basal levels as the furosemide dose was increased to 9.

[A rotary rasp as an aid in the foot care of cattle (author's transl)].

The use of a rotary metal rasp, mounted on a right-angled, as in aid in the foot care of cattle is described. The results obtained with this instrument were satisfactory. This device will save a considerable amount of (physical) labour as well as time, especially in cattle with particular hard feet (such as A.