Latin America and the Caribbean Region population projects : 1990-91 Edition / Latin America and the Caribbean Region population projects : 1990-91 Edition

New estimates of trends in demographic indicators from the 1970s and revised projections for all countries and economies in the Region

Age-specific growth rates: the legacy of past population dynamics.

Recent developments in population mathematics have focused attention on a function that is widely available but rarely examined: the set of age-specific growth rates in a population. In particular, this set of rates is sufficient for translating the current birth rate and age-specific mortality rates into the current age distribution. This growth-rate function contains all of the pertinent features of a population's demographic history that are required to relate major demographic functions for a particular period to one another. This article presents an expression for the age-specific growth rate and uses it to derive an equation for age distribution. We show how the value of the age-specific growth rate is determined by a population's demographic past and present various sets of growth rates corresponding to stylized demographic scenarios. Several noteworthy sets of growth rates observed in human populations are discussed. Finally, we explain why age-specific growth rates make it possible to determine the age distribution solely from information on current demographic conditions.

Stability over time in the distribution of population forecast errors.

A number of studies in recent years have investigated empirical approaches to the production of confidence intervals for population projections. The critical assumption underlying these approaches is that the distribution of forecast errors remains stable over time. In this article, we evaluate this assumption by making population projections for states for a number of time periods during the 20th century, comparing these projections with census enumerations to determine forecast errors, and analyzing the stability of the resulting error distributions over time. These data are then used to construct and test empirical confidence limits. We find that in this sample the distribution of absolute percentage errors remained relatively stable over time and data on past forecast errors provided very useful predictions of future forecast errors.

Using Medicare data for short-run projections of the elderly population.

As the elderly population of the United States grows in absolute number and as a proportion of total population, accurate projections of that population become increasingly important for sound policy decisions. Cohort component techniques are typically used for state and local projections of the elderly population, but are often outdated or even nonexistent for many local areas. This paper suggests an alternative approach, based on Medicare data and simple projection techniques. Projections for several base periods and projection horizons are made for all states and for counties in Florida and are compared with actual Medicare enrollment. On the basis of these comparisons it appears that Medicare data and simple projection techniques can produce very useful short-run projections of the elderly population for states and local areas.

Population, environment, medicine and global sustainability.

The final two decades of this century see our planet in a highly perilous condition. This paper, after touching on the problem of nuclear proliferation, goes on to consider three other issues overpopulation, environmental depredation and the future of medical practice all of which are of high salience. The section on population concentrates on the time required for numbers to stabilize at two children per family. Europe is likely to attain stabilization before 2050, North America and the USSR by 2100. In the developing world South and East Asia could also be in balance by the beginning of the twenty-second century; but the situation in Africa vis-à-vis population growth is much more serious and stabilization cannot be anticipated until about 2150. Destruction of life support systems on a massive scale continues, particularly in developing countries. Much of Asia, Africa and Latin America is riddled with soil erosion; expanding populations of humans and livestock are proving a notable catalyst to desertification; the 'firewood crisis' is deepening as slowly but surely the earth is being deforested. There is little convincing evidence that the major aims of the World Conservation Strategy maintenance and responsible utilization of essential ecological systems, preservation of genetic diversity are being obeyed anywhere in the world. In the more sustainable society of the future engineering medicine with its proclivity for resource depletion will be less attractive. Rather will the emphasis be on prevention and on attempting to delineate the environmental factors known to be responsible for an increasing number of diseases. The likely pattern of morbidity and mortality in the twenty-first century is discussed. Geriatric medicine will hold pride of place; the incidence of cancer will rise markedly, and as an increasing number of Third World nations undergo the process of development diseases, which up till now have mainly affected affluent technological societies, it will spread throughout the planet.

Population, food and nutrition during the remainder of this century: Part I. World prospects.

People mainly depend on food that can be produced on arable land. However, the amount of this land is strictly limited and is less than is generally assumed. Particularly in the developing countries it is usually very fully exploited, but the crop yields obtained are poor and all too often the productive capacity is steadily decreasing. Efforts to improve conditions were often successful, but they have been largely arrested by the rapid rise in the cost of energy. These improvements were partly responsible for a slight rise in the standard of living, sufficient to cause a corresponding slight reduction in the awesome rate at which the population was increasing. For the same reason this encouraging tendency can no longer be expected; indeed it will be reversed. Other adverse effects must be expected from this new factor which will increase the gravity of a situation already so very serious. More and more people cannot be nourished by land that is becoming less and less productive. But how can the nations be awakened from their mutual suspicions and fears? From their preoccupation with creating ever more deadly tools of destruction? How can they be made to see the magnitude of the danger which will affect them all? Is there not an urgent need for them to draw on their immense resources and engage in a concerted effort, on an adequate scale, to win what is becoming a war for survival?

Population, food and nutrition during the remainder of this century: Part II. South Africa.

Whether South Africa can grow enough food over the next 20 years to meet the needs of a population estimated to be increasing by up to 1 million a year depends primarily on the extent, nature and condition of its natural resources and secondly on how they will be conserved and used. These, together with other relevant matters, are the subjects considered for both White and Black areas, especially as they affect the production of our basic foodstuff--maize. The maize production potential of the homelands is considerable, but at present they are largely dependent on imports obtained from White farms. Possible reasons for this unhealthy state of affairs are discussed. What can be done to enable the homelands to make their contribution to the food supplies of the country?

Population forecasts for health planning: an assessment of the state of the art.

Health planning agencies make use of age-sex detailed forecasts of population. This article evaluates sources of forecasts, notes the essential role of assumptions in forecasts, and indicates the general quality of techniques for projecting components of population change. It clarifies for health planners what demographers can--and can not--deliver.

The elderly in family practice: an evaluation of the geriatric visiting nurse.

The Geriatric Visiting Nurse (GVN) is a health-care professional who, assisted by a checklist, screens patients in their homes, carries out basic tests, and facilitates effective follow-up of patients. Utilization of the GVN in a rural Well-Elderly Clinic associated with the University of Iowa Department of Family Practice is described, and the GVN's participation in the clinic is compared with the screening services provided for physicians by geriatric nurses in advanced communities in various countries. Subject to careful planning, the GVN can play an important role in case-finding, and can, when incorporated into the family practice team, promote efficient utilization of the physician's time.