The quality and comparability of child care data in U.S. surveys.

This paper examines the quality and comparability of child care data obtained from eight waves of data from four nationally representative data sources: the National Longitudinal Survey of Youth (1986 and 1988), the Survey of Income and Program Participation (1986, 1987, 1988, and 1990), the National Child Care Survey, and the National Survey of Families and Households. We examine whether different study designs and survey techniques for asking questions about child care produce similar results on both the levels and determinants of child care. We identified four main sources of difference in the data sets that could impact the quality and comparability of child care research: when the interview is conducted; screening questions used to determine who is asked about child care; the population of parents and children represented in the survey; and the way child care questions are asked. Our findings indicate that summer interviews and screening on mother's work status produce the largest differences in the levels and effects of child care across these studies. Even after removing the effects of summer interviews and screening questions, however, substantial differences exist across the studies.

Reexamining the link of early childbearing to marriage and to subsequent fertility.

Using data from the 1980, 1985, and 1990 Current Population Surveys, we show that the link between early fertility and nonmarital births has become stronger. Women who give birth earlier are increasingly likely to be unmarried. In contrast, we find a weaker association between first births at young (versus older) ages and (1) a rapid pace of subsequent childbearing and (2) higher completed fertility. We discuss possible causes and consequences of these changes.

Geographic information systems, spatial network analysis, and contraceptive choice.

How does family planning accessibility affect contraceptive choice? In this paper we use techniques of spatial analysis to develop measures of family planning accessibility, and evaluate the effects of these geographically derived measures in a multilevel statistical model of temporary method choice in Nang Rong, Thailand. In our analyses we combine spatial data obtained from maps and Global Positioning System (GPS) readings with sociodemographic data from surveys and administrative records. The new measures reveal (1) important travel time effects even when family planning outlets are close by; (2) independent effects of road composition; (3) the relevance of alternative sources of family planning supply; and (4) the importance of the local history of program placement.

Education and the changing age pattern of American fertility: 1963-1989.

Using pooled data from the 1980, 1985, and 1990 Current Population Surveys, we describe fertility trends by age and education for the period 1963-1989. Interest focuses on whether the effects of education have changed across this period. We show that women with college degrees experienced dramatic shifts toward later ages of childbearing. This shift is consistent with arguments we develop about the increased opportunity for women to pursue careers and about changes in the availability of child care.

The initiation of adolescent sexual and contraceptive behavior during changing times.

This paper examines changes in the initiation of adolescent sexual and contraceptive behavior in the United States between 1978 and 1988. Since a number of contextual changes occurred during this time period including a focusing of public attention on adolescent pregnancy along with the widespread publicity surrounding AIDS, we expected that the response to these events not only would change over time, but would also vary across social groups. Using data from Cycles III and IV of the National Survey of Family Growth, we find that the overall population patterns of earlier initiation of sexual intercourse and increased use of condoms at first intercourse are not found in all segments of the population. In general, the effects of race, religion, mother's education, and age changed during this time period. The long-term trend of younger age at first intercourse was halted for Blacks, and reversed for White, fundamentalist Protestants, but continued for all other Whites. Overall, patterns throughout the decade suggest that pressures from parents, religious groups, and others either lead to a later age at first intercourse, or use of contraception, but not both. A notable exception is that increased maternal education leads to both a later age at first intercourse and a higher likelihood of using contraception at first intercourse.

PIP: Over the period 1978-88, the US public gave increasing attention to adolescent pregnancy and AIDS. In that context, one might expect changes in the initiation of adolescent sexual and contraceptive behaviors. The authors examined such changes. The analysis of data from the third and fourth cycles of the National Survey of Family Growth failed to demonstrate the existence of trends toward the earlier initiation of sexual intercourse and increased use of condoms at first intercourse in all population segments. The effects of race, religion, mother's education, and age changed during the period. The long-term trend of younger age at first intercourse continued for all Whites except those who are fundamentalist Protestants, ended for Blacks, and reversed for White, fundamentalist Protestants. Overall patterns throughout the decade suggest that pressures from parents, religious groups, and others lead to either a later age at first intercourse or use of contraception, but not both. Increased maternal education, however, leads to both a later age at first intercourse and a higher likelihood of using contraception at first intercourse.

Community and contraceptive choice in rural Thailand: a case study of Nang Rong.

This paper blends quantitative with qualitative data in an investigation of community and contraceptive choice in Nang Rong, Thailand. Specifically, it develops an explanation of 1) method dominance within villages, coupled with 2) marked differences between villages in the popularity of particular methods. The quantitative analysis demonstrates the importance of village location and placement of family planning services for patterns of contraceptive choice. The qualitative data provide a complementary perspective, emphasizing the importance of social as well as physical space and giving particular attention to the structure of conversational networks.

Adolescent contraceptive method choices.

This article analyzes determinants of contraceptive method choices among adolescent women in the United States. By using data from the 1982 National Survey of Family Growth, we examined factors that differentiate users of various methods early in the sexual careers of teenaged women. We find that patterns of method choice not only vary by race and region within the United States but also change over the teenager's life course. In addition, among teenagers who did not use a method at first sex, the likelihood of adopting a method soon thereafter was low for both whites and blacks and was unaffected by social structural characteristics.

Medical and contraceptive reasons for sterilization in the United States.

Over the past two decades, the proportion of sterilizations--for both contraceptive and noncontraceptive reasons--among women of reproductive age (WRA) has risen in the United States. In 1982, more than one in ten WRA were sterilized for noncontraceptive, or medical, reasons. However, the rationales these women had for undergoing sterilization were not always clear-cut; often a mixture of medical and contraceptive reasons were given. In this study, Cycle III data from the National Survey of Family Growth, 1982, were used to investigate the determinants of different types of sterilization decisions--sterilizing for contraceptive, medical, or "mixed" reasons. It is important to recognize this "mixed" component of sterilization motivation. Parity and, to a lesser degree, education have consistent effects on differentiating these types of rationales, which appeared to have somewhat different patterns among black and white women.

Racial differences in contraceptive choice: complexity and implications.

Previous research has failed to generate consensus about why black fertility has persistently exceeded that of whites in the United States. In an effort to shed light on this question, this article examines black/white differences in sociodemographic factors affecting contraceptive choice. Using data from the 1976 and 1982 National Surveys of Family Growth, we find a complex pattern of black/white differences. Not only does contraceptive choice vary by race, but the effects of such variables as age, marital status, and education also differ between blacks and whites. For example, compared with whites, black married women avoid coital methods, and compared with blacks, white women shift contraceptive behavior more as they change marital status. The complex nature of the racial differences in contraceptive choice are interpreted as reflecting differences in marriage patterns and trends.

Analyzing fertility histories: do restrictions bias results?

The straightforward tests we have conducted lead to two major conclusions. First, parameter estimates, such as the proportions that practice contraception or that breastfeed, can be biased in data restricted to the last closed and open interval. This is particularly true the further back in time one goes. However, the second conclusion is that these restrictions do not bias estimates of the structure of the relationships predicting fertility. This may seem surprising, and perhaps even magical. The reason is that multivariate life table techniques allow one to reach the same conclusion even if the proportions in various categories are altered by a criterion such as limiting the analysis to intervals begun by the last and next-to-last live births. Limiting the analysis in this way means that there are fewer short intervals and thus fewer cases of intervals with characteristics associated with short intervals (e.g., no contraceptive use, no breastfeeding, or infant mortality). As long as the model specified in the multivariate life table is an appropriate one, that is, it is not misspecified, and as long as the skew produced by the WFS restriction is not too extreme, then the multivariate life table procedures can produce unbiased estimates of the structure of the relationships predicting birth interval dynamics. Thus even though the WFS data are in fact inappropriate for some simple parameter estimation procedures, they appear to be adequate for the more complex multivariate procedures of the sort used here. Several caveats must be added to the foregoing results. First, we have performed this test in only one country, Korea; it is possible that the same results might not be obtained in other countries. We expect, however, that they would. Second, our procedure only looks at the first 40 months of experience in the birth interval. A procedure that incorporates the long tails of the birth interval distribution may obtain different results. In fact, we caution against analyzing the tail of the distributions using data from the normal WFS sample, since these would be most affected by the restriction to last closed and open intervals. Third, the extent to which these results are generalizable to other types of substantive problems is unknown at present. We suspect, however, that examining the determinants of lengths of breastfeeding will produce similar results. Finally, even with multivariate procedures, it would be highly misleading to impose the WFS restrictions and then examine trends in the length of birth intervals.(ABSTRACT TRUNCATED AT 400 WORDS)

The effect of marital dissolution on contraceptive protection.

An analysis of data from the 1973 and 1976 National Surveys of Family Growth indicates that although marital disruption affects contraceptive practice, the patterns of contraceptive behavior among separated women who remain sexually active are very similar to those of women who remain married. Women about to separate rely less on barrier methods than do continuously married women, and this pattern persists after separation. It is likely that coitus-related methods are less frequently used because they require cooperation between the spouses. In addition, coitus-related methods are probably used less after separation because these methods are less effective, and unintended pregnancies are less desirable in the intermarital or postseparation period. As might be expected, both before and after separation, women who experience marital dissolution are less likely than the continuously married to be sexually active. The difference is greater after separation, but the major finding is the similarity of separated and continuously married women with respect to both coitus and contraceptive protection.

PIP: An analysis of data from the 1973 and 1976 National Surveys of Family Growth indicates that although marital disruption effects contraceptive practice, the patterns of contraceptive behavior among separated women who remain sexually active are very similar to those of women who remain married. The strategy of this study was to select a reference month (R) randomly from the monthly histories of women who were married throughout the observation period. This resulted in a set of reference months that are distributed in approximately the same fashion as the months in which the separations occurred. At the reference point, the study groups consisted of 1232 women about to separate and 14,237 women who would remain married. The number of cases declined with increasing distance from R; nonetheless, the estimates are remarkably stable over time. Between 1 month before separation and 4 month later (R+3), the proportion of separated women not exposed increase from 7 to 24%. However, during the same period, there is only a minor decline in the proportion of separated women who remain protected by pill use, and virtually no decline in the proportion sexually active and using the IUD. The proportion of separated women who were protected against pregnancy by use of these 2 methods dropped remarkably little--from 43% at R-3 to 37% at R+3. Women about to separate rely less on barrier methods than do continuously married women, and this pattern persists after separation. Whereas 87% of the continuously married continue to use these methods for the period in question, only 33% of separated women do so. It is likely that coitus related methods are less frequently used because they require cooperation between the spouses. In addition, coitus-related methods are probably used less after separation because these methods are less effective, and unintended pregnancies are less desirable in the intermarital or postseparation period. A marked reduction in protection by male sterilization occurs following separation. 75% of separated women, compared with 85% of married women, continued to use the pill after the reference month. As might be expected, both before and after the separation, women who experience marital dissolution are less likely than the continuously married women to be sexually active, 22% compared with 2%. The difference is greater after separation, but the major finding is the similarity of separated and continuously married women with respect to both coitus and contraceptive protection.

The transition to motherhood: the intersection of structural and temporal dimensions.

PIP: Prior work on the determinants of the 1st-birth process can be divided into 3 approaches: 1) time-series analysis focusing on description and determinants of trends; 2) cross-sectional studies examing childlessness or adolescent fertility; and 3) life-course studies dealing with the timing of fertility relative to other events. Drawing on these traditions, the conceptual framework places the 1st-birth process within, respectively, an aggregate-time dimension indicated by period or cohort, an individual-time dimension indicatedd by the respondent's age, and a social-structural dimension indicated by the respondent's spanning the 1955-1976 period, and examining conditional birth probabilities, the analysis incorporates each of these dimensions. Each dimension is important. Aggregate time exerts powerful and pervasive effects. Socio-structural variables have nonproportinal effects--tht is, their effects vary with time. The effects of the social-structural variables tend not to interact with the aggregate-time dimension. Finally, predictive power generally declines with inndividual time.^ieng

Measurement and replication: evaluating the consistency of eight U. S. fertility surveys.

This paper addresses the comparability of data from eight national fertility surveys conducted in the United States between 1955 and 1980. We examine the extent to which substantive conclusions about the levels and correlates of the timing of first birth vary across these data sources by comparing samples of women who were eligible to be included in more than one study. Results obtained from Ordinary Least Squares (OLS) and logistic regression analyses of several measures of timing indicate few study effects. Thus findings based on data from one survey can be replicated with comparable data from another. One notable exception is the relationship between contraceptive use prior to the first birth and the timing of that birth. The contraceptive variable appears to be poorly measured, leading to unstable estimates of the relationship. In general, our results suggest: (1) the feasibility of pooling data from the various surveys when modeling delayed childbearing; and (2) reasonable accuracy in assessing trends in the timing of first birth from multiple data sources.

Household structure and the tempo of family formation in comparative perspective.

Summary Previous research on the relationship between extended family residence and fertility has produced conflicting findings. In the present paper, we avoid a major shortcoming of past work by focusing on residence and fertility at a given stage of the life-cycle, i.e. the stage following first marriage. Results show that residence with husband's parents reduces age at marriage. Residence with wife's parents shows no such consistent effect. No evidence was found to support the claim that extended family residence consistently affects the length of the interval between marriage and the first birth. These findings are consistent across four cultural/ethnic groups.

Those ubiquitous fertility trends: United States, 1945-1979.

PIP: 1970-79 US fertility trends among differnet racial, regional, age, educational, parity, and socioeconomic subgroups in the population were examined, using own children data from the 1976 Survey of Income and Education (SIE) and the March Current Population Surveys (CPS) from 1968-80. In addition, cross-sectional differences in fertility for the subgroups were compared for 1970 and 1976, using multiple regression analysis. 1st, the appropriateness of using fertility rates obtained from own children data was assessed by comparing fertility rates obtained from the SIE data with those derived from vital statistic and census data. The comparative analysis confirmed that the SIE data yielded an accurate estimate of period fertility rates for currently married women, provided the subgroup samples were sufficiently large. CPS fertility estimates were also judged to be accurate if data from 3 adjacent survey years was pooled to increase sample size. Fertility trends for 5 educational groups were assessed separately for 1967-73. During this periold, there was a marked decline in fertility for all 5 groups; for the group with 5-8 years of education the decline was only 14%, but for the other 4 groups, which included women with 9-16 or more years of education, the decline in fertility ranged from 26-29%. In assessing the 1970-76 trends, the sample was restricted to own children, aged 3 years or less, of currently married women, under 40 years of age. Among whites, there was an overall 20% decline in fertility between 1970-76 and an overall fertility increase of about 2% between 1976-79. These trends were observed in all 28 white subgroups. A similar pattern was observed for blacks. There was an overall fertility decline of 24% between 1970-76, and this decline was apparent for all subgroups except women with college degrees. Betwen 1976-79, black fertility rates, unlike white rates, continued to decline, but the rate of decline was only 3%. Furthermore, the decline in almost all the black subgroups was markedly less than in the 1970-76 periold, and for many of the subgroups the trend was reversed and fertility increased. In summary, the fertility trends noted for 1970-79 were pervasive for almost all the subgroups for both blacks and whites; i.e., there was a marked decline in fertility between 1970-76 and than a reversal or slowing down of the decline during the 1976-79 for all black and white subgroups. Cross-sectional fertility differences in the subgroups in 1970 and in 1979 were quite similar, and fertility rates differed markedly for the separate subgroups. These differences do not, of course, explain the pervasive trends observed in the analysis of the fertility rates over time. A similar study assessing fertility trends among subgroups for the early 1940's through the late 1960s also revealed the pervasive nature of period fertility trends. Demographers have not as yet been able to explain these shifts in fertility that cut across all subgroups in the US and which also characterize the period fertility rates in other developed countries. Tables provided information on 1) total fertility rates by educational level and by geographical region for 1945-1975; 2) % change in number of own children less than 3 years of age among women under age 40 by maternal age, maternal education, initial parity, geographical region, and husband's income; and 3) mean number of own children less than 3 years of age among women under age 40 by maternal age, education, parity, region, and husband's income.^ieng

Intermediate variables and educational differentials in fertility in Korea and the Philippines.

This analysis compares the effects of contraceptive use and infant and fetal mortality on the pace of fertility in Korea and the Philippines and explores the mediating effects of these intermediate variables on educational differentials in childspacing. For both intervals initiated in a recent period before a sample survey, second, third and higher-order intervals are examined. Transitions within successive segments of interval exposure (qx values) are examined rather than cumulative transitions (1 - lx values). This methodological choice is substantively important because breastfeeding should primarily affect early segments of exposure and because it allows empirical examination of the timing of the effects of other variables such as contraceptive use. Further, this choice allows multivariate analysis within the structure of the life-table perspective. The results show substantial differences in patterns between Korea and the Philippines, indicate clearly the effect of each intermediate variable, and illustrate how educational differentials in fertility are affected by contraception and infant and fetal mortality.

Selectivity and the analysis of birth intervals from survey data.

PIP: Birth interval analysis is used increasingly by demographers because of the precision it allows in studying the effects of intermediate variables on fertility, and because of the new availability of retrospective birth history data from the World Fertility Survey. 3 principal methodological issues surrounding birth interval analysis are identified: data quality, the "censoring" problem, and selectivity bias. This technical report focuses on selectivity in the analysis of birth interval data from retrospective birth surveys. The nature of this generally unrecognized problem is reviewed, and strategies are suggested that will minimize or eliminate the bias in analyses of differentials and trends.^ieng

Earnings, relative income, and family formation.

The probability of first marriage for men who graduated from Wisconsin high schools in 1957 was analyzed with respect to their Social Security earnings records, Wisconsin income tax reports for parents, and other variables. The findings provide no support for Easterlin's hypothesis that marriage will occur earlier when young men judge their economic prospects favorably with respect to their parents' income. However, young men's earnings and time spent in schooling to increase them were found to be important influences on marriage timing. Additional schooling had little effect net of the time it absorbed.