[The 'Anemia in the midwife practice' standard issued by the Royal Dutch Organisation of Midwives: a risk of not recognizing iron deficiency and hemoglobinopathy]. / De standaard 'Anemie in de eerstelijns verloskundige praktijk' van de Koninklijke Nederlandse Organisatie van Verloskundigen (KNOV): risico voor het niet onderkennen van ijzergebrek en hemoglobinopathie.

The standard entitled 'Anaemia in the midwife practice' issued by the Royal Dutch Organisation of Midwives presumes that the only reason for iron therapy in pregnancy is the prevention of adverse pregnancy outcome due to a low haemoglobin level. Pregnant women are screened for iron deficiency anaemia by means of sequential testing of haemoglobin and mean corpuscular volume (MCV). As a result only 10% of pregnant women will receive iron supplements. This practice will lead to a deterioration in the already low iron status of Dutch premenopausal women. As the haemoglobin reference values are lower than hitherto used, only severely anaemic women will be detected. Due to the low diagnostic accuracy of the MCV test the subsequent selection will be an arbitrary one. The standard sets the cut-off values for haemoglobin in black women at an even lower level, which will reduce the number of haemoglobinopathies detected in the immigrant population. The non-carriers in this group will run an increased risk of adverse pregnancy outcome if these cut-off values are used. We are strongly in favour of the measurement of haemoglobin, erythrocyte indices and ferritin in early pregnancy. In this way, iron deficiency, iron deficiency anaemia, anaemia due to other causes and haemoglobinopathies, the latter highly underestimated in the standard, can be detected.

[Iron deficiency in premenopausal women and criteria for iron supplementation]. / Ijzergebrek bij premenopauzale vrouwen en criteria voor ijzersuppletie.

Currently iron deficiency is treated only when anaemia has developed. In premenopausal women a haemoglobin level lower than 7.5 mmol/l justifies the diagnosis of anaemia. Reference values for haemoglobin in women have, however, been established while excluding only the extreme iron-deficient group, in which no iron could be found in the bone marrow. Studies on iron substitution in sufficient dosage in premenopausal women recorded haemoglobin values rising up to > or = 8.0 mmol/l. Premenopausal women will benefit from iron supplementation to optimize haemoglobin values and iron stores. Their physical condition is directly proportional to haemoglobin values. When pregnancy occurs sufficient iron stores corresponding to a ferritin value of > or = 80 micrograms/l are beneficial to mother and child. There are no rational arguments to refrain from iron supplementation in premenopausal women with suboptimal iron stores.

A microcomputer network for the differential leucocyte count and the registration of red blood cell morphology.

A microcomputer network is described for the scoring of the differential leucocyte count and the registration of white and red cell characteristics. On each terminal keyboard, keys are assigned to white cell fractions (10), erythroblasts (1), red (13) and white (3) cell morphology and for graduations 1+ to 4+. Duplicate counts on different microscopes are collected by the master, averaged and forwarded to a printer. In the future we hope to transmit results directly to the laboratory computer. The use of the system is not restricted to the differential leucocyte count. An intelligent scoring board can help to alleviate the time-consuming task of entering qualitative and descriptive results into a laboratory computer.

Analytic precision in clinical chemistry and medical decisions.

A study was undertaken to answer the question: how precise do measurements in clinical chemistry have to be to contribute positively to patient treatment. Sixty-three senior specialists in internal medicine, working in university and teaching hospitals, were interviewed on a number of subjects related to medical decision-making. Hospital laboratories tested samples of quality-control sera to obtain information about intra- and interlaboratory variability. Data for normal range values were reported by laboratories. The tests evaluated in this study were: sodium, potassium, chloride, calcium, inorganic phosphorus, urea, creatinine, glucose, cholesterol, total protein, lactate dehydrogenase, alkaline phosphatase and hemoglobin. Three criteria were applied to test whether analytic precision met present medical needs: (1) the difference between normal range limits and action levels (a value prompting the clinician to action, e.g., repeated or additional testing, in the outpatient situation; (2) a medically significant change in a patient's condition, assuming an initial value in the near-abnormal range; (3) clinicians' feeling of satisfaction or dissatisfaction with laboratory performance. Except for calcium, median analytic precisions of laboratories participating in the study were adequate to record a change in the condition of a patient with a value in the near-abnormal range (second criterion). In order to distinguish the individual with a disease from the normal population, more tests need improvement: calcium, creatinine, glucose, cholesterol, total protein, alkaline phosphatase, lactate dehydrogenase and hemoglobin (first criterion). This finding largely agrees with physicians' satisfaction or dissatisfaciton (third criterion).

Quality control in clinical chemistry: the two-sample plot and improvement of laboratory performance.

A two-sample plot is often used to display test results in clinical chemistry external quality control programs. The use of control materials at different concentrations calls for a re-evaluation of the two-sample plot. A modification of the two-sample plot is presented. The axes of the graph are graduated in units of measurement rather than standard deviation intervals. The mean of all laboratories or a reference laboratory's value is entered as the target value. For each laboratory, repeated results for the same or similar control materials are recorded. Visual inspection of the graph gives immediate information as to the extent of intra-laboratory variability, the incidence of systematic errors in the laboratory, and the size and type of systematic errors (proportional or constant) with respect to the target value.