[Odds ration and relative risk: confounded effects?]. / Odds Ratio und Relatives Risiko: Vermengte Effekte?

This paper defines some epidemiological and arithmetrical terms. Three examples demonstrate confounded effects between age and exposure to risk factors. For prognostic purposes the cross-product ratios are not helpful.

[Critical commentary about the CARE study]. / Kritischer Kommentar zur CARE-Studie.

After a brief description of the CARE-Study this paper demonstrates: Complications of the coronary arteriosclerosis occur independent of the cholesterol- and LDL concentrations. Consequences are discussed.

[Cholesterol and coronary sclerosis]. / Cholesterin und Koronarsklerose.

This paper defines the terms logic, cause, and risk. Furthermore this paper shows; High serum cholesterol concentrations do not cause the sclerosis of the coronary arteries. Therefore, interventions are useless.

[Butter and total cholesterol]. / Butter und Gesamtcholesterin.

This paper gives reasons for the following statements: 1. Restricted consumption of butter does not influence the physiological cholesterol levels. 2. An association between high cholesterol levels and the incidence of coronary sclerosis can not be demonstrated. 3. Hitherto all intervention trials do not show any effect. 4. No longer serum cholesterol can be considered as a factor of risk.

Recent results of the German Thorotrast study--epidemiological results and dose effect relationships in Thorotrast patients.

The German Thorotrast Study includes 5159 Thorotrast patients and 5160 control patients. 887 Thorotrast patients and 660 control patients could be clinically and biophysically examined and followed-up. The mean age at injection or hospitalization in the case of the control group was 28 yr. The mean injected volume of Thorotrast was calculated to be 24.7 ml and the X-ray films of 249 Thorotrast patients showed paravascular deposits. In the meantime 432 Thorotrast patients and 122 patients of the control group have died. Among the deceased patients we have registered (Thorotrast vs control): hepatic tumors 152/0; myeloproliferative diseases 10/0; Hodgkin's diseases 2/0; non-Hodgkin's lymphomas 5/1; bronchogenic carcinomas 13/6; pleural mesothelioma 1/0; bone sarcoma 1/1(?); sarcoma at injection site 1/0; hepatic cirrhosis 90/6; bone marrow failure 8/1; other neoplastic diseases 46/19; other non-neoplastic diseases 151/88. The cumulative incidence of liver tumors depends on the dose rate to liver tissue and is not influenced by the age at injection. A dose effect relationship for the myeloproliferative diseases is not yet apparent.

Recent results of the German Thorotrast study--statistical evaluation of animal experiments with regard to the nonradiation effects in human thorotrastosis.

Our first long-term animal experiment made use of 1920 female Wistar rats divided into 20 groups of 96 animals each. These were injected at 12 weeks of age with different volumes and different dosages of Thorotrast which was enriched with 230Th to enhance the alpha-energy emission rate. The purpose of the study was to evaluate the effects due to the colloidal substance and the radiation. In the main experiment, 12 groups of rats were injected intravenously with 60, 120 and 300 microliters Thorotrast. 230Th was added to some Thorotrast preparations so that the total alpha-energy emission rate varied by factors of 1, 2, 5 and 10 relative to normal Thorotrast. Two groups were injected with 12 and 60 microliters of 50-fold enriched Thorotrast. One group was given 600 microliters of normal Thorotrast. In addition, we had 5 control groups, 1 NaCl and 4 Dextrin groups. The latter were injected with 60, 120, 300 or 600 microliters of Dextrin. The first animals died 8 months after injection, and the last 11 animals were killed 41 months after starting the experiment. The number of animals that developed a hepatic or splenic tumor increased by a factor of 10 in the highest dose-rate groups compared to controls. Our results demonstrated a linear correlation between the dose-rate and the number of primary hepatic and splenic tumors. It appeared that the volume of injected Thorotrast, by itself, had little influence on the number of tumors. However, at a constant dose-rate of 10, a 50-fold increase in the volume of Thorotrast (12-600 microliters) decreased the minimal tumor-appearance time by about 250 days.

Radiological kidney size in childhood.

Kidney length (KL), renal area and renal parenchymal area were measured on i.v. urograms of 255 children without apparent kidney disease age 0 to 14 years. These parameters were compared with age, body height, body surface area and the distance between the 1st and 4th lumbar vertebral body. In addition, renal parenchymal thickness was determined at the upper and lower poles. Mean values for normal KL were significantly greater on the left side than on the right side requiring separate growth charts. A mean increase in KL of 6.3 mm for the left and 6.0 mm for the right kidney was calculated for a change of 10 cm body height. A small kidney is defined by a KL below--2 SD for the corresponding body height and/or a quotient of right KL/left KL outside +/- 2 SD from the mean value. Localised loss of renal parenchyma is reflected by an increased or decreased quotient of the upper to the lower polar thickness and reduction of total kidney mass by a diminished bipolar parenchymal thickness related to body height.

[Planning of psychotropic drug trials. Statistical evaluation. Hypotheses and methods]. / Planung von Psychopharmakaprüfungen. "Statistische Auswertung". Voraussetzungen und Methoden.

Any reasonable evaluation presupposes a precise question. Furthermore it is necessary to eliminate all factors of disturbance, which are able either to simulate or to mask a result of evaluation. The most important of these factors is the psychiatrist himself. Therefore, experimental designs have to taken in account the factor psychiatrist. Criteria of the effects of any drug must be relevant with regard to comparison of two or more drug effects. The reproduciability of criteria is very desirable, but a wish-fulfilment under the most circumstances. Because criteria should be independent and mutually exclusive, all scales like the Hamiltons one are not suitable for evaluation. Finally one should use as few criteria as possible. Models of evaluation are described for the most frequent questions in connection with clinical trials in psychopharmacology.

[Statistics and comparative pharmacokinetics (author's transl)]. / Statistik und vergleichende Pharmakokinetik

An example stresses the point of well established routines, which are usual in comparative pharmacokinetics today. It seems to be necessary to analyse the problem carefully, before starting any pharmacokinetical trial.