Carolina Population Center
Carolina Population Center
Goldberg S.K.,University of North Carolina at Chapel Hill |
Halpern C.T.,University of North Carolina at Chapel Hill |
Halpern C.T.,Carolina Population Center
Perspectives on Sexual and Reproductive Health | Year: 2017
CONTEXT: The typical understanding of sexual debut as first vaginal intercourse is often irrelevant to sexual minority youth. Better understanding of sexual initiation patterns among these youth is necessary to inform efforts to safeguard their sexual and reproductive health. METHODS: Early sexual experiences were examined among 1,628 female and 526 male sexual minority participants in Waves 1 (1994–1995) and 4 (2008) of the National Longitudinal Study of Adolescent to Adult Health. Latent class analyses identified initiation patterns distinguished by the timing, sequence and spacing of first experiences of sexual behaviors. Multinomial logistic regression analyses assessed correlates of various patterns. RESULTS: Initiation classes for females were categorized as typical debut (representing 41% of the sample, characterized by vaginal intercourse and short spacing between first two behaviors); dual behavior debut (35%, characterized by vaginal and oral sex in the same year); early sexual debut (17%, characterized by average debut at 13, vaginal intercourse, and anal sex before 18); and delayed debut with oral sex (6%). Male classes were single behavior (50%, characterized by oral sex and longer spacing); multiple behavior (32%, characterized by vaginal and oral sex); early anal sex (11%, characterized by anal intercourse before 18); and very early debut (6%, characterized by oral sex and average debut at 10). Class membership was associated with socioeconomic status for females; age and sexual victimization for males; and race, ethnicity and religiosity for both. CONCLUSIONS: Initiation patterns of sexual minority youth differ between genders and involve noncoital behaviors and characteristics beyond timing. Copyright © 2017 by the Guttmacher Institute
News Article | April 19, 2017
The Centers For Disease Control and Prevention notes that over one-third of U.S. adults suffer from obesity. Americans spend roughly $1,429 more on medical bills and care of obese people, when compared to people with normal weight. One of the main reasons behind this serious condition is the consumption of soft drinks. In 2014, in a bid to cut down the sales and consumption of sugar-sweetened beverages or SSBs, tax on these drinks was introduced in Berkeley, California. This move was the first of its kind in the United States. At the time, people were apprehensive as to how a tax would cut down soda sales, but apparently the method has been successful in reducing soda sales. Since the tax was levied, the sales of soft drinks in Berkeley has declined by more than 9 percent. Moreover, a new study reveals that there has been a substantial increase in sales of bottled water. Health officials in Berkeley were optimistic that increased prices of unhealthy drinks would deter people from purchasing them and, therefore, proposed levying a substantial tax on SSBs. The soda tax proposal received approval in November 2014 and came into effect in the region from Jan. 1 2015. The tax added one cent per fluid ounce to the soft drink can or bottle. Therefore, according to the tax rules a person has to pay 12 cents extra for a 12-ounce soda can, which was earlier priced at $1. Similarly, one has to pay an additional 68 cents for a 2-liter soft drink bottle, which was priced just a little over $2 before the tax was levied. Added costs to SSBs makes them more expensive and may convince a thirsty individual, who is short on cash, to opt for water instead. Moreover, other than diverting people to a healthy lifestyle, the tax also provides the city with added revenue. Researchers from the Carolina Population Center at the University of North Carolina and the Public Health Institute teamed up to observe the link between the SSB tax and soda sales, price, consumer spending, and many more factors. "This study examines the association of the first penny per ounce SSB excise tax in the United States, in Berkeley, California, with beverage prices, sales, store revenue/consumer spending, and usual beverage intake," shared the researchers. This is not the first time a study has been conducted in Berkeley to see whether the SSB tax has had any desired effect on the population and its soda drinking habits. A similar study was conducted in fall 2016 and showed that SSB consumption in Berkeley decreased by 21 percent. The study also revealed that after the SSB tax was imposed, water consumption in Berkeley increased by 63 percent. The 2016 fall study on Berkeley SSB tax was published in American Journal of Public Health. The researchers studied the SSB sales in Berkeley from March 1, 2015 to Feb. 29, 2016. During this period, the researchers observed the prices of soft drinks at 26 stores in Berkeley. The team also looked into the point-of-sale scanner data of more than 15 million SSB items at two supermarket chains, three stores in Berkeley, and six more stores in the nearby cities. The researchers also conducted a telephonic survey with 957 residents in Berkeley. After a thorough examination, the researchers found that sales of SSBs in Berkeley declined by 9.6 percent during the study period. On the other hand, the sales of bottled water increased by 15.6 percent during the same time period. Taking into account the fact that Berkeley already had a low consumption rate of SSBs, the additional decline surprised the researchers. "I didn't think we'd get much effect at all," said Barry Popkins, one of the researchers of the study. The findings of the study have been published in journal PLOS Medicine, on Tuesday, April 18. © 2017 Tech Times, All rights reserved. Do not reproduce without permission.
Curtis S.,University of North Carolina at Chapel Hill |
Sambisa W.,Carolina Population Center
International Perspectives on Sexual and Reproductive Health | Year: 2011
CONTEXT: Contraceptive discontinuation is a common event that may be associated with low motivation to avoid pregnancy. If this is the case, a substantial proportion of pregnancies that follow discontinuation will be reported as intended. METHODS: Demographic and Health Survey data from six countries (Bangladesh, the Dominican Republic, Kazakhstan, Kenya, the Philippines and Zimbabwe) over the period 1999-2003 were used to explore the proportions of pregnancies women reported as intended or unintended following various contraceptive behaviors. Multivariate logistic regression analysis was used to examine the characteristics of women who reported births as intended when they followed contraceptive failure or discontinuation for reasons other than a desire for pregnancy. RESULTS: The proportion of births reported as intended following contraceptive failure ranged from 16% in Bangladesh to 54% in Kazakhstan, and the proportion reported as intended following discontinuation for reasons other than a desire for pregnancy ranged from 37% in Kenya to 51% in Kazakhstan. In at least half the countries, associations were found between selected women's characteristics and their reports that births following either contraceptive failure or discontinuation were intended: Factors that were positively associated were women's age and the time elapsed between contraceptive discontinuation and the index conception; factors that were negatively -associated were increasing number of living children and reporting method failure as opposed to method discontinuation. CONCLUSION: These findings suggest that underlying variation in the motivation to avoid pregnancy is an important factor in contraceptive discontinuation.
Siddiqi A.,Carolina Population Center
Journal of Epidemiology and Community Health | Year: 2010
Background: Cross-national comparisons allow the examination of the malleability of associations between race and health. Racial inequities in chronic conditions, indicators of health status and behavioural risk factors between two similar advanced capitalist countries were compared. It was hypothesised that racial inequities will be mitigated in Canada compared with the USA. Methods: Population-based, cross-sectional data from the 2002-3 Joint Canada-USA Survey of Health (JCUSH) with 4953 adult respondents from the USA and 3455 from Canada. Models adjusted for age, sex, foreign birth, marital status, health insurance, education, income and home ownership. Results: Compared with the USA, racial inequities in health were attenuated in Canada. In the USA, racial inequities in chronic diseases and fair or poor self-rated health were largely driven by inequities found among the native born. Strikingly, in Canada, however, there were few significant racial inequities and those occurred exclusively among the foreign born. Within strata of race and foreign birth, Canadians fared better, with both white people and non-white people reporting better health than their American counterparts. Foreign-born Canadians and Americans were more similar to each other in terms of health than native-born Canadians and Americans. Only among the native born did American white people and American non-white people have higher adjusted odds of hypertension, diabetes and obesity than Canadian white people and Canadian non-white people respectively. Self-rated health was worse for non-white Americans than non-white Canadians regardless of foreign birth. Conclusion: The influence of race on health is context dependent. There is no necessary link between race and a variety of health indicators.
News Article | November 8, 2016
Providing pregnant and postpartum women in sub-Saharan Africa with multiple HIV self-tests can make it more likely their male partners will be tested for HIV compared to a standard approach of distributing invitation cards for clinic-based testing, according to a randomized trial published in PLOS Medicine by Harsha Thirumurthy of the University of North Carolina at Chapel Hill, USA, and colleagues. Low use of testing services in sub-Saharan Africa, particularly by men, is one of the key barriers to meeting targets that UNAIDS has set for HIV prevention. Moreover, efforts to encourage pregnant women and postpartum women to refer their partners for testing and to test as a couple, in order to help prevent mother-to-child transmission of HIV, have had limited success. Between June and October 2015, Thirumurthy and colleagues enrolled in their study 600 women seeking pregnancy and postpartum care at three facilities in Kisumu County, Kenya. All women enrolled were 18-39 years old, had a partner that was not known to be HIV-positive, and agreed to participate. Half the women were given two oral fluid-based HIV self-test kits to take home, instructions on use, and were encouraged to give a test to their male partner or to test with their partner if they felt comfortable. The other 300 women were given invitation cards to give their partner for HIV testing at a clinic. Over the following three months, women were followed up to determine if their partner had self-tested or visited a clinic to test for HIV. In the group that received HIV self-tests, 90.8 percent of partners were reported to have tested within 3 months of enrollment in the study. In the comparison group, 51.7 percent of partners were reported to have visited a clinic for HIV testing. Based on these results, self-tests led to 39.1% more partner testing than the control (95% confidence interval 32.4% to 45.8%, P "The promising results from this study suggest that secondary distribution of self-tests warrants further consideration as countries develop HIV self-testing policies and seek new ways to promote partner and couples testing," the authors say. The study was funded by the International Initiative for Impact Evaluation (TW2-02-02). HT acknowledges support from the Eunice Kennedy Shriver National Institute of Child Health and Human Development (K01HD061605). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. The authors have declared that no competing interests exist. Masters SH, Agot K, Obonyo B, Napierala Mavedzenge S, Maman S, Thirumurthy H (2016) Promoting Partner Testing and Couples Testing through Secondary Distribution of HIV Self-Tests: A Randomized Clinical Trial. PLoS Med 13(11): e1002166. doi:10.1371/journal.pmed.1002166 Department of Health Policy and Management, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America Department of Health Behavior, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America Carolina Population Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America IN YOUR COVERAGE PLEASE USE THIS URL TO PROVIDE ACCESS TO THE FREELY AVAILABLE PAPER:
Saville B.R.,Vanderbilt University |
Herring A.H.,University of North Carolina at Chapel Hill |
Herring A.H.,Carolina Population Center |
Koch G.G.,University of North Carolina at Chapel Hill
Statistics in Medicine | Year: 2010
We consider regulatory clinical trials that require a prespecified method for the comparison of two treatments for chronic diseases (e.g. Chronic Obstructive Pulmonary Disease) in which patients suffer deterioration in a longitudinal process until death occurs. We define a composite endpoint structure that encompasses both the longitudinal data for deterioration and the time-to-event data for death, and use multivariate time-to-event methods to assess treatment differences on both data structures simultaneously, without a need for parametric assumptions or modeling. Our method is straightforward to implement, and simulations show that the method has robust power in situations in which incomplete data could lead to lower than expected power for either the longitudinal or survival data. We illustrate the method on data from a study of chronic lung disease. Copyright © 2009 John Wiley & Sons, Ltd.
Lenhart P.M.,University of North Carolina at Chapel Hill |
Nguyen T.,Harvard University |
Wise A.,University of North Carolina at Chapel Hill |
Caron K.M.,University of North Carolina at Chapel Hill |
And 3 more authors.
American Journal of Perinatology | Year: 2014
Objective Reduced maternal plasma levels of the peptide vasodilator adrenomedullin have been associated with adverse pregnancy outcomes. We measured the extent to which genetic polymorphisms in the adrenomedullin signaling pathway are associated with birth weight, glycemic regulation, and preeclampsia risk. Study Design We genotyped 1,353 women in the Pregnancy, Infection, and Nutrition Postpartum Study for 37 ancestry-informative markers and for single-nucleotide polymorphisms in adrenomedullin (ADM), complement factor H variant (CFH), and calcitonin receptor-like receptor (CALCRL). We used linear and logistic regression to model the association between genotype and birth weight, glucose loading test (GLT) results, preeclampsia, and gestational diabetes (GDM). All models were adjusted for pregravid body mass index, maternal age, and probability of Yoruban ancestry. p values of < 0.05 were considered statistically significant. Results Among Caucasian women, ADM rs57153895, a proxy for rs11042725, was associated with reduced birth weight z-score. Among African-American women, ADM rs57153895 was associated with increased birth weight z-score. Two CALCRL variants were associated with GDM risk. CFH rs1061170 was associated with higher GLT results and increased preeclampsia risk. Conclusion Consistent with studies of plasma adrenomedullin and adverse pregnancy outcomes, we found associations between variants in the adrenomedullin signaling pathway and birth weight, glycemic regulation, and preeclampsia. Copyright © 2014 by Thieme Medical Publishers, Inc.
Halpern C.T.,University of North Carolina at Chapel Hill |
Halpern C.T.,Carolina Population Center |
Whitsel E.A.,UNC CH |
Wagner B.,UNC CH |
And 3 more authors.
Psychoneuroendocrinology | Year: 2012
Objectives: Longitudinal examinations of associations between daily stress, diurnal cortisol concentrations, and physiological parameters in population-based studies are needed. This study evaluates issues related to consent, collection, and protocol adherence for a low-burden saliva collection protocol. Methods: In the 2007 pretest (n=193) for Wave IV of the National Longitudinal Study of Adolescent Health (Add Health) a three-sample, one-day, unsupervised saliva collection protocol was pilot tested. Embedded experiments allowed for examination of adherence and effects of monetary incentives. Results: Although most (97%) study participants consented to collection, only about 80% actually mailed back samples. Use of a time-stamping TrackCap allowed comparison of self-reported and stamp-recorded collection times. Of returned samples, self-report of collection time was missing for about a quarter, and only about one in three respondents (of those for whom adherence was calculable) fully adhered to the collection protocol, indicating significant potential for bias. Consent, return, and protocol adherence were unrelated to key sociodemographic characteristics, and did not improve with higher monetary incentives or knowledge of being monitored. Conclusions: Despite the relatively low-burden collection protocol and use of multiple strategies thought to improve collection and protocol adherence, response and adherence were poor, leading to a decision to drop cortisol measurement from the Wave IV Add Health protocol. Large field studies should carefully evaluate the feasibility of collection and protocol adherence for unsupervised collection protocols before implementing costly, and potentially unusable, biological measurements. © 2011 Elsevier Ltd.
Thompson A.L.,Carolina Population Center |
Adair L.S.,Carolina Population Center |
Bentley M.E.,Carolina Population Center |
Bentley M.E.,University of North Carolina at Chapel Hill
Pediatrics | Year: 2013
OBJECTIVE: This study examines the development of television (TV) behaviors across the first 18 months of life and identifies maternal and infant predictors of infant TV exposure. METHODS: We used longitudinal TV exposure, maternal sociodemographic, and infant temperament data from 217 African-American mother-infant pairs participating in the Infant Care and Risk of Obesity Study. Longitudinal logistic models and ordered regression models with clustering for repeated measures across subjects adjusted for infant gender and visit were used to assess maternal and infant predictors of TV exposure and to test whether infants with both maternal and infant risk factors had higher odds of more detrimental TV exposure. RESULTS: Infants as young as 3 months old were exposed to an average of 2.6 hours of TV and/or videos daily, and nearly 40% of infants were exposed to .3 hours of TV daily by 12 months of age. Maternal TV viewing and maternal obesity and infant activity, fussiness, and crying were associated with greater infant TV exposure, whereas maternal education and infant activity were associated with having the TV on during most meals. Infants perceived as being more active or fussier had higher TV exposure, particularly if their mothers also had risk factors for higher TV exposure. Copyright © 2013 by the American Academy of Pediatrics.
Popkin B.M.,Carolina Population Center |
Popkin B.M.,The Interdisciplinary Center
Health Affairs | Year: 2010
Nationally representative surveys of food intake in U.S. children show large increases in snacking between the 1989-91 to 1994-98 and 1994-98 to 2003-06 periods. Childhood snacking trends are moving toward three snacks per day, and more than 27 percent of children's daily calories are coming from snacks. The largest increases have been in salty snacks and candy. Desserts and sweetened beverages remain the major sources of calories from snacks. © 2010 Project HOPE-The People-to-People Health Foundation, Inc.