[Evaluation of pipetting systems. II. Precision and accuracy of precision dispensers].

Objective: To evaluate the precision and accuracy of the liquid dispensers being used in our institution.

Material: A total of 15 dispensers (8 micro and 7 macro) of automatic, semiautomatic or manual types were evaluated. They had been in use from 0.

[Patient data for evaluating reference values].

Objective: To explore the use of data in patients as a way to evaluate the values of reference in clinical assays. Serum calcium (Ca) and phosphorus (P) were selected for this purpose.

Material: A total of 836 consecutive admissions in a 10 week period were revised.

Red cell indices in normal adults residing at altitude from sea level to 2670 meters.

Hemoglobin (Hb), packed cell volume (PCV), red blood cells (RBCs), mean cell volume (MCV), and mean cell hemoglobin concentration (MCHC) were measured by a single operator in a single laboratory by means of an electronic particle counter in 942 healthy adults (491 females and 451 males) residing at five altitudes: 0, 1000, 1860, 2220, and 2670 meters above sea level. The subjects were carefully screened clinically, and subjects with low transferrin saturation (less than 15%) were excluded. In both sexes there was a differential behavior as a function of altitude, of Hb and PCV on the one hand, and number of RBCs on the other.