Changes in EEG order in neuroleptically treated normal volunteers during a voluntary movement task.

15 normal volunteers were treated over three weeks with haloperidol (HAL) and in the third week additionally with biperidene (BIP). The order of the EEG spectra at different topographical locations and in different frequency bands during a movement task was analyzed using uncertainty analysis (UA), a multivariate analysis technique based on information-theoretical methods. Different patterns of drug-induced changes were found. HAL decreases the theta and alpha band order at the fronto-central lateral areas but increases it at the fronto-central midline in the theta band and at the parietal areas in the alpha band. With the exception of the fronto-central midline locations, BIP more or less counterbalances the effect of HAL. Volunteers felt unwell and had motor disturbances during HAL and felt well again during HAL + BIP. Reaction time values were increased during HAL and normalized during HAL + BIP.

Quality management in managed care.

Managed care creates a corporate environment in which competitiveness demands close attention to quality. Although the health care sector may benefit from solutions derived in other industries, it attaches unique importance to noneconomic, intangible factors. Adequate cost-utility analysis must take such factors into account instead of relying on artificial numerical values.

Changes in functionally determined order processes of the EEG in a motor task due to various dosages of biperidene.

Animal experiments have demonstrated that the cholinergic system plays an important role in the activation of the cerebral cortex in conjunction with motor activities. In order to study the significance of the cholinergic system in the generation of voluntary movements in man, the effects of the anticholinergic drug biperidene on EEG states were analyzed. The effects depend strongly on the dosage and are shown in various frequency bands, topographic loci and time periods. Different functional significances of various frequency bands were found. In the alpha band motoric control processes are seen as an expression of mechanisms which substitute the cholinergic system. A shift of functions from the theta to the delta band with the increase of the medication seems to parallel an enhancement of motivational or volitional effort. The emergence of highly ordered EEG states is seen to be meaningful in view of the underlying processes of voluntary movements.

Program evaluation: considerations of effectiveness, efficiency and equity.

Health programs should be effective in reaching their objectives and should do so through efficient use of scarce resources. Moreover, the benefits should be equitably distributed among the targeted beneficiaries. The individual desirability of these attributes of program success is unquestioned, but their mutual compatibility should be. Narrowly based programs might be very efficient, whereas expansion into more difficult areas could be costly. Moreover, the difficult areas are likely to comprise disadvantaged groups that are inequitably served at present.The paper argues that measures of effectiveness, efficiency and equity need to be more sharply defined, so that trade-offs in program emphasis can be objectively assessed. Methods of analysis that make the trade-offs clear are pre-sented and applied to real data taken from a family planning study in India.

Applicability of industrial sampling techniques to epidemiologic investigations: examination of an underutilized resource.

In carrying out surveys to estimate disease prevalence or health services coverage in a region, investigators are often interested in identifying communities or other subareas in which the problem of interest is especially severe. In view of the large number of subareas to be examined, the investigator seeks rapid methods of assessment that require minimum sampling in each. Lot quality assurance sampling, developed more than 60 years ago to meet industrial quality control needs, has been found to serve public health purposes as well. Curiously, other more recent and more powerful industrial techniques have not received the recognition they deserve. Several of them are discussed in this paper and likely applications are cited. They fall into two categories: 1) lot acceptance methods to depict static conditions in a population and 2) more dynamic process monitoring methods for continuous surveillance. Under the first category, techniques of double sampling and sequential sampling are described. Reduced and tightened scrutiny, control charts, and exponential smoothing are highlighted as especially promising approaches under the process control category.

Blood viscosity in small tubes: effect of shear rate, aggregation, and sedimentation.

Apparent viscosity was determined in vertical glass tubes (ID 30.2-132.3 microns) with suspensions of human red cells in A) serum, B) saline containing 0.5 g/100 ml albumin, C) plasma, and D) plasma containing Dextran 250 at a feed hematocrit of 0.45. Pressure-flow relationships were obtained in a range of pseudo-shear rates (mu) between 0.15 and 250 s-1. Relative viscosities in the nonaggregating suspensions (A and B) were found to increase monotonically with decreasing mu. The Fahraeus-Lindqvist effect was present in the entire range of mu. In the two aggregating suspensions (C and D), viscosities increased initially in larger but not small tubes with declining mu and fell in all tubes at some characteristic mu (usually below 10 s-1). Viscosity reduction was greater in the larger tubes and in suspensions with greater aggregation tendency. With suspension D, the Fahraeus-Lindqvist effect was eliminated in the lowermost shear-rate range. The cell-free marginal zone increased in width (to a maximum of approximately 40% of tube radius) as viscosity declined. Measurements of viscosity and cell-free marginal zone were also performed with suspension C in tubes mounted in horizontal position. In contrast to vertical tubes, a monotonic increase in viscosity was found with decreasing mu, associated with cell sedimentation and development of a cell-free layer only in the upper portion of the tubes.

Uncertainty analysis of human EEG spectra: a multivariate information theoretical method for the analysis of brain activity.

Short time Fourier power spectra yield activity related data of the EEG. The mean power densities of frequency bands have proved a reliable descriptive parameter of that activity. Due to their distributional properties of these data their analysis by conventional statistics is restricted to nonparametric univariate or at most bivariate tests. In order to account for the many-relational characteristics of EEG data, uncertainty analysis was employed and specific data transformations were developed. This technique was applied to some of our experimental records. The results confirm prior knowledge of the functional diversity of brain areas and demonstrate the general applicability of uncertainty analysis to this problem. In addition, the spatio-temporal coordination of these activities suggests a systems interpretation: These neuronal processes follow the self-organizing principle.

Effect of shear rate variation on apparent viscosity of human blood in tubes of 29 to 94 microns diameter.

In order to test the hypothesis that the increase of vascular resistance observed in vivo at low flow rates is due in part to blood rheological properties, the apparent viscosity of human blood was measured in small tubes in a range of shear rates. Pressure-flow relationships were obtained in vertical glass tubes (29 to 94 microns i.d.) perfused with blood at hematocrits between 0.13 and 0.65. Viscosity of blood and plasma was calculated using Poiseuille's law. With the exception of data obtained in the largest tube at a hematocrit of 0.6, relative blood viscosity was found to be independent of shear rate in the range between 1 and 120 s-1. Microscopic observation revealed pronounced red cell aggregation at low shear rates. Velocity profiles obtained by the use of fluorescence-labelled red cells showed increased blunting with decreasing shear rate. The Fahraeus-Lindqvist effect was evident in a reduction of viscosity with tube size at a given feed hematocrit. The observed constancy of apparent blood viscosity with decreasing shear is attributed to the opposing effects of a cell-depleted marginal layer and red cell aggregation or deformation in the cell core. The findings indicate that the increase of vascular resistance at low arterial pressure cannot be explained by shear-dependent changes of apparent blood viscosity observed in macroviscometers.

Statistical analysis of interdependence of country health resource variables, with special regard to manpower-related ones.

The analysis reported here was the latest in a series of efforts to clarify the relative importance of the health system and of socioeconomic factors to a nation's general level of health. The study has also quantified national and regional deviations from the general pattern as a basis for selective investigation of the effects of planned interventions.The analysis was unusually comprehensive in that it included 131 WHO Member States. As in a number of other studies, socioeconomic factors were found to account for much of the national variation in life expectancy. Inclusion of health resource variables added a special lagged effect which ultimately accounted for 90% of life expectancy variation. Evidence was also obtained that socioeconomic factors may operate partially through the development of health resources. It appears, therefore, that though socioeconomic factors are necessarily linked to health improvement, they are not sufficient in the absence of corresponding development of a viable health services infrastructure.Residual deviations from the general pattern varied systematically by WHO region in 30% of the cases. Most notably, in the African Region the number of physicians is well below even the modest level expected on the basis of the socioeconomic situation in the region. There is, however, considerable variation within individual countries, and it was not possible to find any significant relationship between the WHO manpower development programme and the national health resource parameters. It is therefore concluded that statistical analysis is of limited applicability in this field.

The unmet demand for health services: a vital component in planning.

Consideration of unmet need as well as effective demand for health services is desirable for planning but frequently ignored. This paper reports an analysis of the findings from a national health survey conducted in Chile to obtain information on both met and unmet demand. The joint analysis proved feasible and highly informative. Total felt need tended to be relatively constant among population groups in comparison with differences in actual services utilization. Moreover, exceptions to this general finding revealed patterns that should improve our insights for health planning.

Alternative methods for determining resource requirements: the Chile example.

Many more or less attractive techniques have been proposed for statistical analyses involving multiple sources of variation, for example in examing the possible contributors to differential patterns of health services utilization and expenditure. A large scale investigation of such patterns among 10,000 household in Chile provided a useful basis for comparison of alternative analytical approaches. The multiple regression, Automatic Interaction Detection, and Multisort techniques were applied to the survey data deparately and in combination and results were compared. The Multisort technique was found to be the single most useful and convenient approach, but the most meaningful results were obtained from the systematic application of the three approaches combined.

Measurement and projection of the demand for health care: the Chilean experience.

Projection of the probable demand for health services over time is one of the most important-and difficult-aspects of the health planning process. Not only must the planner contend with many variables external to the health sector, but also with the difficult to predict correlations between the supply of health, services and the resultant demand. This article briefly reviews some of the principal demand projection methods in use and then describes in detail the one adopted in the Chilean health manpower study. The demand portion of the study in Chile involved three main elements: 1) a sample survey which measured the met and unmet demand for medical, dental, and hospital services as a function of six population variables (age, sex, location, income, educational level, and medical insurance status); 2) a baseline demand projection which takes into account the probable effects of changes in these six variables over ten and 20 years on the utilization of services; and 3) an alternative projection which postulates the fulfillment of certain targets for the improvement of health care. The approach offers the planner a number of important analytical and programmatic advantages compared with other methods now available and are discussed along with their limitations.

Methodologic issues in population planning: studies of alternative patterns of administrative organization.

PIP: A systematic framework for the organization of family planning programs includes the specification of the problems, the assessment of the resources available, and then the establishment of objectives regarding the program structure, process, and result. Some of principals involved in administration of family planning programs are the needs for 1) development in a national context; 2) marketing methods; 3) central policy planning; 4) operations-oriented research; 4) political support; and 5) evaluation. No single system of organization for family planning programs is optimal, but this analysis may help to define problems involved administration.^ieng