The historical calendar as a method of estimating age: The experience of the Moroccan multi-purpose sample survey of 1961-63

Abstract In censuses and surveys in most African countries it has become the practice to estimate informants' age by the method of the historical calendar. This involves an attempt to relate a remembered historical event, occurring during the subject's childhood, with his age at the time. This paper attempts a first evaluation of the method with particular reference to the 1961-63 multi-round survey in rural Morocco. It is shown that in practice the method is highly complex and easily misunderstood by interviewers and respondents. An attempt to lay down a precise procedure by means of a very detailed questionnaire appeared to yield at best only marginally more accurate results than the simpler procedure used in an earlier round. The more complex questionnaire did, however, introduce new patterns of misuse by the interviewer. There was evidence that the historical calendar gave somewhat better data than eye estimates, but results were highly defective for both methods. It is clear that the method is far from perfect. Interviewer training and supervision remain the key to accurate age determination. If the potential benefits of the complex historical calendar method are to be realized, training and supervision need to be even more thorough than where simpler methods are used.     

Note on the use of statistics of total fertility to provide estimates of crude birth rates

It is shown that estimates of the total fertility by age of mother can be used to give good rough approximations to birth rates in under-developed countries and that this method is likely to be more accurate than the collection of historical data relating to particular calendar periods.     

The contribution of medical measures to the decline of mortality from respiratory tuberculosis: An ageperiod-cohort model

The decline of mortality in the more developed nations has been related to two major influences, economic development and the introduction of medical measures. The contribution of medical measures has been a source of continuing controversy. Most previous studies employ either a birth cohort or calendar year arrangement of mortality data to address this controversy. The present study applies an age-period-cohort model to mortality from respiratory tuberculosis in England and Wales, Italy, and New Zealand in an attempt to separate economic influences from that of medical measures. The results of the analysis indicate that while the overall contribution of medical measures is small when examined by calendar year, specific birth cohorts both in Italy and in England and Wales benefited substantially from these measures. The environmental conditions in New Zealand, however, were such that the introduction of medical measures barely affected declining mortality levels from respiratory tuberculosis.     

A reply to Kim's comment

This reply criticizes Kim's note as incorrectly characterizing the essential feature of the method proposed for life table construction. The method suggested for estimating N(a), the number attaining age 2 during the intercensal period, is to make a separate estimate of the contribution to N (a) made by each single-year cohort that attains 'a' during the period between censuses. Each cohort estimate is constructed by interpolation, utilizing as data the recorded number in the relevant single-year cohorts in the 2 censuses. 2 methods of interpolation were proposed. 1 is an iterative procedure that constructs a preliminary life table by linear interpolation for each cohort and then derives more refined interpolation factors from this preliminary life table. The other procedure derives interpolation factors on the assumption that the proportionate distribution of deaths by age as each cohort moves from the earlier to the later census date is the same as the proportionate distribution of deaths by age over the same age range in a model life table. The advantage of the proposed procedure is that it supplies better estimates of N (a) than do alternative methods. The author concedes that a life table calculated from accurately recorded deaths and an accurately enumerated population would ordinarily be superior. However, he also notes that in the absence of registered deaths data, there is no precise enough conventional method to yield accurate values of average intercensal single-year age-specific mortality rates from nothing more than 2 accurate censuses 11 years apart. A common procedure for calculating life expectation at a very advanced age is to calculate the reciprocal of the death rate among persons over the age in question.     

Determinants of contraceptive switching behavior in rural Sri Lanka

This study examines the influence of a selected set of determinants of contraceptive method switching in rural Sri Lanka. Of interest is the question of how change in contraceptive practice at the individual level can account for patterns observed at the aggregate level. Based on calendar data on contraceptive use over a 3-year period, collected for more than 3,000 married women in a 1986 survey, the multivariate analysis shows that women who attain all or a significant proportion of their desired fertility tend to switch to more effective methods. Women who experience method failure tend to switch methods, usually to a type that is more effective. The woman's background determinants of age and education have small but significant effects on method switching, whereas the effect of household economic well-being is not significant. There is strong indication that rural couples are practicing contraception in a nonrandom fashion, switching methods in accordance with changes in their fertility motivations and contraceptive experience.     

Effects of targets and aggregation on the propagation of error in mortality forecasts

Official forecasts of mortality depend on assumptions about target values for the future rates of decline in mortality rates. Smooth functions connect the jump‐off (base‐year) mortality to the level implied by the targets. Three alternative sets of targets are assumed, leading to high, middle, and low forecasts. We show that this process can be closely modeled using simple linear statistical models. These explicit models allow us to analyze the error structure of the forecasts. We show that the current assumption of perfect correlation between errors in different ages, at different forecast years, and for different causes of death, is erroneous. An alternative correlation structure is suggested, and we show how its parameters can be estimated from the past data.

The effect of the level of aggregation on the accuracy of mortality forecasts is considered. It is not clear whether or not age‐ and cause‐specific analyses have been more accurate in the past than analyses based on age‐specific mortality alone would have been. The major contribution of forecasting mortality by cause appears to have been in allowing for easier incorporation of expert opinion rather than in making the. data analysis more accurate or the statistical models less biased.     

Historical,Economic, and Political Contexts of Aging in African America

ABSTRACT

This article is an attempt to present some of the historical and political contexts of older women in general and to communicate pieces of the lives of African American older women, in particular. It presents some of the present day distortions as well as a sense of the historical, economic, and political realities of older African American lives, while trying to limit the use of the usual comparison approach to this topic.     

Urbanization and fertility: An event-history analysis of Coastal Ghana

In this article, we undertake an event-history analysis of fertility in Ghana. We exploit detailed life history calendar data to conduct a more refined and definitive analysis of the relationship among personal traits, urban residence, and fertility. Although urbanization is generally associated with lower fertility in developing countries, inferences in most studies have been hampered by a lack of information about the timing of residence in relationship to childbearing. We find that the effect of urbanization itself is strong, evident, and complex, and persists after we control for the effects of age, cohort, union status, and education. Our discrete-time event-history analysis shows that urban women exhibit fertility rates that are, on average, 11% lower than those of rural women, but the effects vary by parity. Differences in urban population traits would augment the effects of urban adaptation itself. Extensions of the analysis point to the operation of a selection effect in rural-to-urban mobility but provide limited evidence for disruption effects. The possibility of further selection of urbanward migrants on unmeasured traits remains. The analysis also demonstrates the utility of an annual life history calendar for collecting such data in the field.     

Relationships Among Older Women Living in a Nursing Home

SUMMARY

Literature suggests that women's skills in establishing close ties with other women help sustain them in old age by giving them a sense of control over their lives. This paper questions how such a notion may apply to women in a nursing home setting and contrasts women's experiences with those of men. It is a reanalysis of data from a previously reported study of institutionalized elders' social networks, this time with a specific focus on women residents' relationships with one another. Here, I consider the role of negative interaction in personal relationships, the meaning of intimacy and reciprocity in the nursing home context, and issues of age and gender. The final section, implications for practice and future research, includes a discussion of the opportunities for and constraints on relationship formation.     

The multistate life table with duration‐dependence

A method for generalizing the multistate, or increment‐decrement, life table to include rates which depend upon duration of exposure to risk, as well as upon age, is proposed. The method is built upon the linear approximation, called the linear integration hypothesis, developed mainly by Rogers and his colleagues. Although the use of rates indexed by duration categories leads to a substantial increase in the state space of the model, it is possible to arrange the rates in such a way that matrices to be inverted are no larger than those encountered in the usual multistate life table. In the more general approach it is possible to derive several new summary indices of the life‐table cohort's history, such as the mean and median time in current status, at any age. The method is illustrated using a simple four‐state marital‐status model which has appeared often in the literature; here, rates of divorce and widowhood vary by duration of marriage as well as age.     

Political History and Disparities in Safe Motherhood Between Guatemala and Honduras

Each year, worldwide, more than 500,000 women die of complications from childbirth, making this a leading cause of death globally for adult women of reproductive age. Nearly all studies that have sought to explain the persistence of high maternal mortality levels have focused on the supply of and demand for particular health services. We argue that inquiry on health services is useful but insufficient. Robust explanations for safe motherhood outcomes require examination of factors lying deeper in the causal chain. We compare the cases of Guatemala and Honduras to examine historical and structural influences on maternal mortality. Despite being a poorer country than Guatemala, Honduras has a superior safe motherhood record. We argue that four historical and structural factors stand behind this difference: Honduras's relatively stable and Guatemala's turbulent modern political history; the presence of a marginalized indigenous population in Guatemala, but not in Honduras, that the state has had difficulty reaching; a conservative Catholic Church that has played a larger role in Guatemala than Honduras in blocking priority for reproductive health; and more effective advocacy for maternal mortality reduction in Honduras than Guatemala in the face of this opposition.     

A problem in measuring infant mortality]

Infant mortality rates refer to the number of infant deaths in a given calendar year divided by the total number of births for the same year. It is argued that this definition presents a logical problem, such that if "infant" is defined as any child less than 1 year old, then the set of criteria for infants born in January of the given calendar year is totally different for that of infants born in December. Due to the tremendous significance of infant mortality rates in assessing the socioeconomic growth of a given area, discrepancies such as the problem presented cannot be easily overlooked, particularly where small populations are concerned. A more accurate yet problematic approach for small populations, i.e., calculating the rate of infant mortality based on infant birthdays, using proposed linear regression scheme is presented.     

Who decides the position for birth? A follow-up study of a randomised controlled trial

BackgroundPhysical benefits are suggested for women and their babies when women adopt an upright position of their choice at birth. Available care options during labour influence women's impressions of what intrapartum care is. This indicates that choice of birth positions may be determined more by midwives than by women's preferences.QuestionThe aims of this study were to investigate factors associated with adherence to allocated birth position and also to investigate factors associated with decision-making for birth position.MethodAn invitation to answer an on-line questionnaire was mailed.FindingsDespite being randomised, women who gave birth on the seat were statistically significantly more likely to report that they participated in decision-making and that they took the opportunity to choose their preferred birth position. They also reported statistically significantly more often than non-adherers that they felt powerful, protected and self-confident.ConclusionsMidwives should be conscious of the potential impact that birth positions have on women's birth experiences and on maternal outcomes. Midwives should encourage women's autonomy by giving unbiased information about the birth seat. An upright birth position may lead to greater childbirth satisfaction. Women's experience of and preferences for birth positions are consistent with current evidence for best practice.     

A comparison of three physical activity programs for health and fitness tested with older women: Benefits of aerobic activity,aqua fitness,and strength training

ABSTRACT

Inactivity has been associated with decreased quality of life of older people, and many physical activity programs are encouraged. However, the heterogeneity of the different exercise programs available is well recognized. The objective was to compare three physical activity programs (strength training, aqua fitness, and aerobic exercise) to discern the differences in the benefits achieved by each of them in older women over a period of 6 months. For that, a double-blind randomized trial sorted 347 women over 50 years old into three groups of exercise programs; they completed three sessions of evaluation that included the measurement of weight and body mass index and used the Senior Fitness Test (SFT) and SF-12 questionnaire. A t-test for related samples compared the evolution of each group, and ANOVA statistic was used to compare the effect of the different exercise programs. The results showed that women should consider performing aerobic activity up to age 60. After that age, aerobic activity or strength training can provide greater benefits.     

Mortality,past and future

The study of mortality in previous centuries and of the trends in recent decades helps to elucidate some present-day medical problems and to contribute to their solution. The author considers, from a historical and socio-economic point of view, the factors which, during the last 200 years, have influenced the trends of mortality. This analysis indicates the lines along which present research, aimed at reducing mortality and extending expectation of life, should be directed.

Infancy (0–1 year): In backward countries, the whole of infancy is a period of high mortality. In progressive countries, on the other hand, the main reproductive wastage is in the ‘perinatal’ period, that is to say, covering stillbirths and deaths during the first week of life. For example, even in New Zealand, the death risk per day is more than eighty times as high during the first week of life than in the following 358 days.

Historical studies and social class comparisons suggest that further reduction of perinatal mortality is likely to depend on socio-economic, housing and cultural factors rather than on improvements in obstetric skill. Evidence cited by the author indicates that a crucial factor may be to provide expectant mothers with adequate rest during the weeks immediately prior to delivery. In general, research into mortality in infancy is too much bounded by a purely medical point of view whereas a socio-medical approach is needed.

Childhood (1–14 years): There has been an immense reduction in childhood mortality during the last 200 years. Less than 200 years ago the mortality among children aged 1–4 and 5–9 years was thirty-three times, and among those aged 10–14 years twelve times, that of the present day. Future reduction of mortality among children will be primarily a function of social factors and trends.

Adolescence and maturity (15–49 years): One of the outstanding trends of the last 200 years has been a relative increase in tuberculosis mortality among those aged 15–49 years, whereas among children tuberculosis has become relatively less important

as a cause of death. Recently, however, there has been a decline in the relative importance of tuberculosis as a cause of death among the adolescent and mature and, among New York males, it now takes second place to the cardiovascular

diseases. The total mortality of people in this age group has fallen, since the sixteenth century, by 77% for men and 81% for women. No spectacular discoveries are needed to reduce the mortality of this group by a further third; in doing this, control of environment will be the important factor.

Later maturity and old age (50 years and over): In the four centuries since the Renaissance the mortality of people over 50 years of age has been reduced by half. Among the factors contributing to this reduction is a fall in mortality due to tuberculosis. But even cancer, which is popularly supposed to have increased, used to be more common in the eighteenth century than it is now and to appear at an earlier. age. Moreover, there has been a change in the organs most commonly affected. The distribution of the greater proportion of cancer in a given population is a function of living conditions in the broadest sense of the term. Studies of groups exposed to carcinorelevant factors suggest that a high incidence of cancer in one organ is associated with a low incidence in other organs. But on many other causes of death at the older ages far more research is required, especially on the cardio-vascular-renal complex, and on the degenerative joint and bone diseases.     

A Cross-Cultural Study of Attitudes Toward and Beliefs About,Male Homosexuality

This study attempted to compare British and Japanese people's beliefs about the etiolology, manifestations, and changes of male homosexuality. A total of 208 participants completed, in their native language, a three-part questionnaire consisting of 81 items, which covered etiological explanations of homosexuality, general attitudes toward the concept and practice of homosexuality, and efficacy of strategies to change homosexuality. It was hypothesized that Japanese would exhibit more negative beliefs about homosexuality than the British and would tend to favor sociological explanations as possible etiological factors whereas British would prefer biological explanatory models. The Japanese were more unfavorable toward homosexuality, showing more reluctance in contact with homosexuals. However, while British supported biological models, Japanese' attitudes ranged widely from social, biological, to cognitive accounts. Implications for approaches to overcome social stigma in the Japanese society are discussed.     

Model-based Clustering of Sequential Data with an Application to Contraceptive Use Dynamics

ABSTRACT

Multi-state models describe the transitions people experience as life unfolds. The transition probabilities depend on sex, age, and attributes of the person and the context. Empirical evidence suggests that attributes that cannot be measured directly may at most be inferred from a long list of observable characteristics. A cluster-based, discrete-time multi-state model is presented, where transition probabilities are estimated simultaneously for several subpopulations of a heterogeneous population. The subpopulations are not defined a priori but are determined on the basis of similarities in behavior in order to determine which women exhibit similar characteristics with respect to method choice, method switch, discontinuation and subsequent resumption of contraceptive use. The data are from the life history calendar based on the Brazilian Demographic and Health Survey 1996. The parameters of the model are estimated using the EM algorithm. Seven subpopulations with heterogeneous transition probabilities are identified.     

Long- and short-term affective states in happiness: Age and sex comparisons

Data from 690 persons in three adult age groups were used to evaluate the generality of a componential model of happiness (Kozma et al., 1990). The model postulates that long- and short-term affective states combine in an additive manner to produce current happiness. The short-term components should be more susceptible to environmental manipulation than the long-term ones and should change more readily with an appropriate experimental manipulation. Subscales of the Memorial University Mood Scale (MUMS) were used to assess short-term affect while the experience subscales of the Memorial University of Newfoundland Scale of Happiness (MUNSH) and Diener's Long-term Satisfaction Scale were used to measure long-term affect. Overall current happiness was assessed by a seven-point avowed happiness rating scale. The Velten mood induction procedure was used to manipulate current affective state. In five of six comparisons, changes on short-term components were significantly greater than on long-term components. Age differences in reactivity to mood induction emerged only when a negative induction procedure was followed by a positive one. Under these conditions, the youngest cohort responded more consistently than the oldest cohort. An additive model, based on long- and short-term affect, age, and sex produced the best explanation for current happiness.     

A comment on Coale's life table construction

In a recent issue of Population Index, Coale (1984) described a method of deriving a life table for an intercensal period separated by T years from 2 census single-year age distributions of a closed population. This note examines the formula used by Coale and points out that although it works well for all practical purposes, the formula with his new growth rate is an approximation, not an identity as is assumed by Coale. The Coale formula involves more steps than the usual method of estmating mortality and yields less accurate results. Coale's formula is explained. In general, in the case under consideration, if a larger cohort is followed by a smaller cohort, the survival probability calculated by the formula exceeds unity, whereas if a smaller cohort is followed by a larger cohort, the calculated survival probability becomes less than unity. The size of the relative cohorts determines the degree of error in the calculated probability. The formula does not give the survival probability of unity as it should if it were an identity. The formula in the continuous time is an identity. Feeney's alternative method presented in Coale's Computational Appendix 3 produces an exact life table without using any formula. Feeney's method is, however, less accurate than the usual method, given the same data, because it omits some information. The Coale procedure losses its usefulness in that it requires extra data manipulation, only to yield less accurate results.