NFP update: researcher cites need to improve instruction

In the Philippines more and more couples are practicing natural family planning (NFP), but there is a need to improve instruction on this method to increase its effectiveness. Calendar rhythm has been the most popular technique of NFP, but failure rates have been high. This could be changed by improved calendar rythm instruction and the introduction of newer, more effective natural techniques like the basal body temperature, cervical mucus, and symptothermal methods. Dr. John E. Laing, in a paper entitled "research on Natural Family Planning in the Philippines," examines the trends in NFP and summarizes major findings of past research related to NFP and the status of current research. It also discusses the implications of such findings for the National Population Program and the needs for current research. Cting World Fertility Survey (WFS) data on 19 developing countries, Laing states that the Philippines is second only to Peru in current and past use of the rhythm method. He also indicates that since the start of the National Population Program in 1971, rhythm has been offered as an official program method. Yet, in the early years of the program rhythm was not promoted as actively as the other family planning methods. In the last few years, program, officials have become more interested in NFP. 1976 National Acceptor Survey (NAS) data showed that rhythm reduced fertility by 78% compared to the condom's 79%, oral contraceptive's 94%, and the IUD's 98%. A comparison of data from the 1972, 1974, and 1976 NAS indicated a decline in continuation rates and an increase in overall pregnancy rates for all methods except rhythm. The overall pregnancy rate of rhythm declined, but there was no significant change in continuation rate. Laing suggests that probably, while the national population program was increasingly recruiting less motivated couples to try other methods, the rhythm acceptors, who were largely self initiated, mantained earlier levels of motivaton. Evidence points to the widespread use of crude formulas that do not take into account individual variations in cycle length. Many users do not even fully understand the mechanism by which rhythm affects fertility. There is also little knowledge among acceptors of the new and more reliable techniques of NFP for identifying the safe and unsafe periods. Despite problems, a considerable number of acceptors still prefer rhythm to other methods. The commission on population has embarked on a solution to some of the problems by committing itself to the training of volunteers of community-based organizations, particlarly lay leaders. 3 large scale projects are planned for this purpose.     

International migration in Asia and the Pacific: trends,problems, and recommendations

Like other parts of the world, the Asia and Pacific region has experienced mass movements of the population within and across countries. This report presents the issues and problems discussed, and the recommendations given at the Expert Group Meeting on International Migration in Asia and the Pacific, held in 1984 in Manila. The 9 issues discussed include: 1) available data on international migration are often inconsistent, incomplete, and inadequate for a thorough analysis of the migration situation; 2) the conventional economic theory of migration, and the modern view are different, but related; 3) are internal and international migration 2 distinct phenomena, or are they simply opposite ends of a continuum ranging from short-distance moves within a country to long-distance moves across national boundaries?; 4) permanent migration from Asia and the Pacific to the US, Canada, Australia, and New Zealand has risen sharply over the the past few years; 5) international migration could have considerable effects on the size, composition, growth, and structure of the populations of both sending and receiving countries; 6) temporary labor migration to the Middle East increased rapidly in the recent past; 7) temporary labor migration has benefits and costs to the home country and to the returning workers and their families; 8) refugee movements within and from Asia have had significant repercussions, not only in the lives of the migrants themselves, but also in the national policies and social structures of the asylum countries; and 9) international migration, if properly controlled and organized, could work for the benefit of every country involved.     

Agency in Fertility Decisions in Western Europe During the Demographic Transition: A Comparative Perspective

We use a set of linked reproductive histories taken from Sweden, the Netherlands, and Spain for the period 1871–1960 to address key issues regarding how reproductive change was linked specifically to mortality and survivorship and more generally to individual agency. Using event-history analysis, this study investigates how the propensity to have additional children was influenced by the number of surviving offspring when reproductive decisions were made. The results suggest that couples were continuously regulating their fertility to achieve reproductive goals. Families experiencing child fatalities show significant increases in the hazard of additional births. In addition, the sex composition of the surviving sibset also appears to have influenced reproductive decisions in a significant but changing way. The findings offer strong proof of active decision-making during the demographic transition and provide an important contribution to the literature on the role of mortality for reproductive change.     

On the Failure of the Bootstrap for Matching Estimators

Matching estimators are widely used in empirical economics for the evaluation of programs or treatments. Researchers using matching methods often apply the bootstrap to calculate the standard errors. However, no formal justification has been provided for the use of the bootstrap in this setting. In this article, we show that the standard bootstrap is, in general, not valid for matching estimators, even in the simple case with a single continuous covariate where the estimator is root‐N consistent and asymptotically normally distributed with zero asymptotic bias. Valid inferential methods in this setting are the analytic asymptotic variance estimator of Abadie and Imbens (2006a) as well as certain modifications of the standard bootstrap, like the subsampling methods in Politis and Romano (1994).