Some estimates of the reliability of survey data on family planning

An opportunity to estimate the reliability of survey data on family planning is afforded by a longitudinal study of fertility in metropolitan areas of the United States. A probability sample of mothers was interviewed six months after the birth of their second child. Data were collected on a number of pregnancies, use of contraception, methods used, and the planning status of each pregnancy, in addition to a wide variety of social and psychological characteristics. Three years after the first interview, the same women were interviewed again and identical questions were asked about the same pregnancies. This paper reports an analysis of the consistency of responses in the basic fertility and contraceptive histories. Given the simplicity of the pregnancy histories, the relatively sophisticated sample interviewed, and the intensive preparation of the research, the reliabilities of data on family planning estimated here are assumed to approximate to an upper limit for such data at the present stage of development of survey techniques. Some suggestions for possible future improvement are included.     

Modelling the Inverse Association between Breastfeeding and Contraceptive Use

Previous studies of the inverse association between breastfeeding and contraceptive use have relied on current status data on at least one of the variables. In this paper we suggest a new way of modelling the joint temporal association of the adoption of contraception and the termination of breastfeeding over the course of a birth interval. The approach is implemented with survey data from rural Mexico. It involves first estimating a competing-risks model in which both hazards are considered simultaneous, together with a set of relevant covariates. Conditional analyses are then carried out to estimate the hazards of each event conditional on the timing of the other. By comparing the covariates, we gauge the extent to which the occurrence of one event raises or lowers the hazard of the other. The results show that, in rural Mexico, the timing of the termination of breastfeeding and that of starting contraceptive use are closely related, and that there exists a surprisingly neat interval of 120 days in which the action takes place.     

The Power of Jonckheere's Test

This paper discusses the power of Jonckheere's test under the ordered alternative hypothesis. It is shown that the power of the test is bounded significantly away from one under certain shift alternatives and sample sizes.     

CAN TRADE REALLY HURT? AN EMPIRICAL FOLLOW‐UP ON SAMUELSON'S CONTROVERSIAL PAPER

This paper investigates Samuelson's [Samuelson, P. A. “Where Ricardo and Mill Rebut and Confirm Arguments of Mainstream Economists Supporting Globalization.” Journal of Economic Perspectives, 18(3), 2004, 135–46] argument that technical progress of the trade partner may hurt the home country. We illustrate this prospect in a simple Ricardian model for situations with outward knowledge spillovers. Within this framework Samuelson's Act II effects may occur. Based on industry level panel data for 17 OECD countries for the period 1973–2000 we show econometrically that the outflow of domestic knowledge via exports or foreign direct investment (FDI) to the rest of the world may have a negative impact on industry output in the home country. This is particularly so when exporting to technologically less advanced countries and, more specifically, China. (JEL F10, F11, F14, O30)     

After Breast Cancer: Sexual Functioning of Sexual Minority Survivors

Research on sexual difficulties after cancer has neglected sexual minority women (SMW); for example, lesbian and bisexual women. Clinicians treating these women are therefore at a disadvantage as they lack information about sexual problems in this population. This study tested the hypothesis that SMW with breast cancer have poorer sexual function than SMW without breast cancer, distinguishing partnered from unpartnered women. Using convenience sample recruitment, we conducted a case-control study to compare survivors of breast cancers who are SMW, in other words, cases to controls, that is, SMW without cancer. Anonymous survey data were collected from 85 cases after they had completed active cancer treatment and 85 age- and partner-status matched controls with no history of any cancer. Participants' self-reported sexual frequency and sexual function measured by the Female Sexual Function Index were evaluated. Cases and controls did not differ in risk of sexual dysfunction or the level of overall sexual functioning; however, cases had lower sexual frequency and scored lower on desire and ability to reach orgasm, and higher on pain compared to controls. Results inform clinicians about sexual minority survivors' sexual domains affected by cancer. When discussing sexual problems and therapeutic options, sexual orientation should be ascertained.     

‘I accept my son for who he is – he has incredible character and personality’: fathers’ positive experiences of parenting children with autism

Literature in the field of autism is largely deficit driven, with a focus on the inabilities of individuals and the negative experiences of families, often characterised by reductive assumptions and tragedy model interpretations. In addition, family-orientated research has generally overlooked the views and contribution of fathers of disabled children, with positive paternal narratives especially scarce. This study explored 198 father perspectives on perceived benefits of parenting their children with autism, gained in response to an open-ended question in an online survey. Key themes relate to appreciating children’s individual qualities, valuing the strong emotional bond, fathers’ own nurturing role and their associated personal development. Findings will be discussed in relation to models of childhood disability and fatherhood.     

Single motherhood by choice: A parenting alternative

The experience of single motherhood by choice has become more prevalent in the last twenty years and yet the literature reveals a dirth of information about this parenting style. This article delineates the experience of choosing single motherhood utilizing artificial insemination by donor. Several issues are examined: (a) emotional factors and personality characteristics of the mother, (b) physiological factors related to artificial insemination, (c) ethical and legal considerations of artificial insemination and single motherhood, and (d) various economic concerns related to single motherhood.Ann Potter completed her Ph.D. in counseling psychology at the University of Nebraska-Lincoln and is Assistant Professor of Nursing at Clarkson College of Nursing, 333 South 44th Street, Omaha, NE 68131. Her current research interests are children and families of alcoholics, nontraditional families including single motherhood by choice, and incest survivors.Patricia Knaub is Associate Dean of the College of Home Economics and Associate Professor of Human Development and the Family at the University of Nebraska-Lincoln. Her address is 105 Home Economics, University of Nebraska-Lincoln, Lincoln, NE 68583-0800. She completed her Ph.D. at Nebraska and current research interests include stress and coping strategies of farm families, successful remarriages, and issues related to conception, including transference of myths and artificial insemination.     

Population momentum: A wider definition

Summary Keyfitz has derived an elegant formula for estimating the ultimate size of an initially stable, growing population that abruptly reduces its fertility to replacement level. Reduction of fertility is achieved by the rather unrealistic device of dividing the original age schedule nffertility rates by the net reproduction rate. Only the inertia of the age distribution is thus accounted for, but not that of the fertility schedule. The key idea of an abrupt imposition of a fixed regimen capable in the long run of generating zero population growth may be retained, but the regimen made more realistic. By elaborating the population setting, such disparate ZPG regimens as reduction of marital fertility by contraception, delayed and/or less universal marriage, raised mortality risks, or permanent net out-migration may be formulated. Convergence of the populaton to stationarity becomes a two-phase process: a primary adjustment period of changing fertility rates followed by a period of age adjustment. The present paper treats what happens when a fixed ZPG sterilization regimen, defined by a minimum age of sterilization γ and constant continuous risk φ of sterilization among unsterilized wives aged γ to β, is imposed abruptly (or else progressively over an interval T) upon an initially stable, growing population. Additional sources of residual growth are: (1) the nine-month lag in sterilization effect owing to pregnancy: (2) the more youthful pattern of child-bearing under sterilization: (3) the extra adjustment period (of length β-γ-0.75) of changing fertility rates; and (4) any delays in exposing elements of the population to the sterilization regimen. Two questions are pursued. First, how important are the additional sources of residual growth? Secondly, how do their relative sizes vary as a function of the characteristics of the initial population?     

Age-related changes in maximal power and maximal heart rate recorded during a ramped test in 114 cyclists age 15-73 years

This study assessed age-related changes in power and heart rate in 114 competitive male cyclists age 15-73 years. Participants completed a maximal Kingcycle ergometer test with maximal ramped minute power (RMPmax, W) recorded as the highest average power during any 60 s and maximal heart rate (HRmax, beats/min) as the highest value during the test. From age 15 to 29 (n = 38) RMPmax increased by 7.2 W/year (r = .53, SE 49 W, p < .05). From age 30 to 73 (n = 78) RMPmax declined by 2.4 W/year (r = - .49, SE 49 W, p < .05). Heart rate decreased across the full age range by 0.66 beats . min( -1 ) . year( -1 ) (r = -.75, SE 9 beats/min, p < .05). Age accounted for only 25% of the variance in RMPmax but 56% in HRmax. RMPmax was shown to peak at age 30, then decline with age, whereas HRmax declined across the full age range.