Methodologic and logistic issues in conducting longitudinal birth cohort studies: lessons learned from the Centers for Children's Environmental Health and Disease Prevention Research

In anticipation of the National Children's Study, lessons can be learned from the smaller birth cohort studies conducted by five Centers for Children's Environmental Health and Disease Prevention Research funded by the National Institute of Environmental Health Sciences and the U.S. Environmental Protection Agency. The populations studied are diverse in ethnicity and social class and reside in urban and rural environments. Although almost all of the centers chose to enroll participants through medical care facilities, they had to develop independent staffs and structures because of the overburdened medical care system. Some of the lessons learned by the centers include the importance of continuous funding, building community partnerships to conduct culturally appropriate research, hiring bilingual and bicultural staff from the community, prioritizing research goals, developing biorepositories to ensure future utility of samples, instituting quality control procedures for all aspects of specimen and data collection, maintaining frequent contact with study participants, ensuring ethical conduct of the research in a changing medical-legal climate, and communicating results in a timely and appropriate manner to participants and the wider community. All centers underestimated the necessary start-up time, staff, and costs in conducting these birth cohort studies. Despite the logistical complexity and added expenses, all centers emphasize the importance of studying the impact of environmental exposures on those children most at risk, those living in minority and low-income communities. These centers present barriers encountered, solutions found, and considerations for future research, with the hope that the lessons learned can help inform the planning and conduct of the National Children's Study.     

U.S. children with emotional and behavioral difficulties: data from the 2001, 2002, and 2003 National Health Interview Surveys

OBJECTIVE: This report presents selected prevalence estimates for children ages 4-17 years with difficulties in emotions, concentration, behavior, or being able to get along with others using data from the 2001, 2002, and 2003 National Health Interview Surveys (NHIS). METHODS: Data for the U.S. civilian noninstitutionalized population were collected using computer-assisted personal interviews (CAPI). In 2001, a total of 10,367 interviews were completed about sample children ages 4-17 years by the member of the household most knowledgeable about the child's health. The number of completed interviews about sample children ages 4-17 years was 9,512 in 2002 and 9,399 in 2003. Questions on children's emotional and behavioral difficulties from the Strengths and Difficulties Questionnaire (SDQ) were first asked in the NHIS in 2001. SUDAAN software was used to tabulate statistics shown in this report. RESULTS: In 2001, 2002, and 2003, approximately 5% of U.S. children ages 4-17 years had emotional or behavioral difficulties, and for approximately 80% of these children, there was an impact on their functioning. Children with difficulties in emotions, concentration, behavior, or being able to get along with others varied by sex, age, race, family structure, poverty status, and health insurance status. About 50% of these children were upset or distressed by their emotional or behavioral difficulties, and about 80% had difficulties that impacted their family life, friendships, learning, or leisure activities.     

Ethnicity and sampling bias in binge eating disorder: Black women who seek treatment have different characteristics than those who do not

OBJECTIVE: The current study investigated sampling bias as it affects recruited clinic samples of Black and White women with binge eating disorder (BED). METHODS: Clinical characteristics of a recruited clinic sample (35 Black and 302 White consecutively evaluated women) with BED were compared with a community sample of Black and White women with BED drawn from the New England Women's Health Project. The clinic and community groups met the same definition of BED and were assessed with identical methods. RESULTS: Among White women, the clinic and community samples differed on some features (higher body mass index [BMI], and greater eating concerns and shape concerns in the clinic sample) but these differences reflected small to moderate effects sizes. In contrast, among Black women, the clinic sample had substantially higher levels (large effect sizes) of several features of eating disorders (eating concerns, dietary restraint, and shape concern), higher (moderate effect size) BMI, but lower frequency of binge eating (moderate effect size) than the community sample. A comparison of Black and White women within the clinic sample revealed little difference in clinical presentation, except for the significantly higher BMI among Black women. CONCLUSION: A sampling bias appears to exist between both White and Black recruited clinic samples of women with BED, although the bias appears to be substantially greater for Black women. Black women with BED who seek treatment have significantly different characteristics than those who do not.     

Geographies of inequality: child pedestrian injury and walking school buses in Auckland, New Zealand

In the face of mounting concern at traffic congestion in the vicinity of schools and the associated risks of child pedestrian injury, the 'walking school bus' (WSB) idea has been rapidly adopted within metropolitan Auckland. WSBs involve volunteers guiding children to and from school in an orderly manner following established walking routes. This paper reports on a survey of the 34 Auckland primary schools which had adopted the scheme by November 2002. Despite rates of child pedestrian injury being highest in areas of socio-economic deprivation, our survey found WSB developments highly concentrated in low deprivation neighbourhoods. The inequitable socio-spatial distribution of WSBs in Auckland suggests that the ability to respond to road safety issues is closely correlated with socio-economic privilege. While our respondents identified a number of individual and community health benefits accruing from WSBs, we conclude that the initiative has a limited ability to address public health challenges originating within an inequitable and car-dominated urban political system.     

Contributions of social science to the alcohol field in an era of biomedicalization

In an era of biomedicalization where findings in genetic and neurobiological research are seen as "breakthroughs" by the media and hence by the general public, it is important for social scientists to acknowledge the effect of their contributions to the alcohol field not only to their own colleagues but also to the public at-large. Contributions of social science research to the development and evaluation of alcohol policies are illustrated in the following four areas: (1) alcohol epidemiological research focusing on the importance of examining drinking patterns and their relation to alcohol-related problems; (2) alcohol's contribution to the burden of disease; (3) alcohol control policies and their impact; and (4) brief interventions that provide strategies for at-risk drinkers as well as those who are alcohol dependent.     

‘Sorry,it's my first time!' Will patients consent to medical students learning procedures?

Context The clinical teaching of medical students is essential to medicine; however, medical students often may not inform patients of their inexperience. Hence patients do not have the opportunity to consent specifically to the procedures being performed by medical students. Objectives The purpose of this study was to determine whether patients, when informed of the inexperience of a medical student, would still consent to the procedure. Methods Adult emergency department patients (114) were enrolled if they required one of the following procedures: sutures, intravenous (i.v.) access or splinting. Patients were first surveyed about his or her perceptions of medical student performing procedures. The first-year medical student then informed the patient of their inexperience (the number of procedures they had performed successfully). Finally, the patient was asked to consent to the student performing the procedure (i.e. ‘this is my first/third time suturing, may I suture you?’) The main outcome measure was patient consent to the student performing the procedure. Results Only 48% of participants knew they could be the first patient on whom a medical student might perform a procedure. A total of 66% thought they should be told if a student was performing his or her first procedure on them. The majority of patients (90%) consented (69/80 i.v., 20/20 splints, 13/14 sutures). For 7 of the 12 refusals, it was the student's first time performing the procedure. Conclusion Most patients will allow medical students to perform minor procedures, even when informed of the student's inexperience.     

Survival of severe congenital diaphragmatic hernia has morbid consequences

Background/Purpose

Fetal tracheal occlusion (TO) was developed in an attempt to enhance prenatal lung growth and improve survival in fetuses with severe congenital diaphragmatic hernia (CDH). We conducted a randomized, controlled clinical trial in 24 fetuses with severe left CDH (liver herniated into the thorax and low lung-to-head ratio) to compare survival after endoscopic fetal TO vs standard perinatal care (control) and prospectively followed up the 16 survivors (9 control, 7 TO) to compare neurodevelopmental, respiratory, surgical, growth, and nutritional outcomes.

Methods

At 1 and 2 years old, subjects underwent evaluation consisting of medical and neurological history and physical, developmental testing, nutritional assessment, oxygen saturation and pulmonary function testing, chest radiograph, and echocardiogram. Growth and developmental measures were corrected for prematurity. Data were analyzed by Mann-Whitney rank sum test, Fisher's Exact test, and logistic and linear regression.

Results

Infants with TO were significantly more premature at birth (control vs TO, 37.4 ± 1.0 vs 31.1 ± 1.7 weeks; P < .01). Growth failure (z score for weight <2 SDs below mean) was severe in both groups at 1 year of age (control vs TO, 56% vs 86%; P = .31). There was considerable catch-up growth by age 2 years (growth failure: control vs TO, 22% vs 33%; P = .19). There were no differences in other growth parameters. There were also no differences in neurodevelopmental outcome at 1 and 2 years. Supplemental oxygen at hospital discharge was a significant predictor of worse neurodevelopmental outcome at 1 and 2 years old (P = .05 and P = .02, respectively). Hearing loss requiring amplification has been diagnosed in 44% of the group (control vs TO, 44% vs 43%; P = 1.0).

Conclusions

In this group of infants with severe CDH, there were no differences in outcome at 2 years old despite significant prematurity in the TO group. Oxygen supplementation at hospital discharge identified the most vulnerable group with respect to neurodevelopmental outcome, but all infants had significant growth failure, and hearing impairment is a substantial problem in this population. Severe CDH carries significant risk of chronic morbidity.     

Low-dose photodynamic therapy increases endothelial cell proliferation and VEGF expression in nude mice brain

We tested whether low-dose photodynamic therapy (PDT) induces an angiogenic response in the normal brain of nude mice (n=20). Normal brains of nude mice were subjected to PDT at low doses (Photofrin: 2 mg/kg; optical: 2 J/cm² and 4 J/cm²). BrdU (50 mg/kg) was injected (intraperitoneally, i.p.) daily from PDT treatment to sacrifice (1 and 2 weeks after PDT). Laser scanning confocal microscopy, immunohistochemistry, and immunofluorescence staining were performed to assay angiogenic response. Morphological results show no significant tissue damage induced by PDT and two- and three-dimensional image analyses revealed no significant difference in vascular structure between the areas of exposure to PDT and contralateral areas in all mice. However, the number of BrdU immunoreactive cells were significantly increased in the areas of PDT treatment compared with contralateral hemisphere in both groups, and the number of BrdU-positive cells increased in a PDT-dose-dependent manner. Furthermore, immunohistochemical data indicate that PDT at these low doses significantly induces the expression of the vascular endothelial growth factor (VEGF) in PDT-treated regions in the 1-week group, but not in the 2-week group. These data indicate that low-dose PDT results in increased VEGF expression and endothelial cell proliferation in normal brains.     

Circulating androgen levels and self-reported sexual function in women

Context  It has been proposed that low sexual desire and sexual dysfunction are associated with low blood testosterone levels in women. However, evidence to support this is lacking. Objective  To determine whether women with low self-reported sexual desire and sexual satisfaction are more likely to have low serum androgen levels than women without self-reported low sexual desire and sexual satisfaction. Design, Setting, and Participants  A community-based, cross-sectional study of 1423 women aged 18 to 75 years, who were randomly recruited via the electoral roll in Victoria, Australia, from April 2002 to August 2003. Women were excluded from the analysis if they took psychiatric medication, had abnormal thyroid function, documented polycystic ovarian syndrome, or were younger than 45 years and using oral contraception. Main Outcome Measures  Domain scores of the Profile of Female Sexual Function (PFSF) and serum levels of total and free testosterone, androstenedione, and dehydroepiandrosterone sulfate. Results  A total of 1021 individuals were included in the final analysis. No clinically significant relationships between having a low score for any PFSF domain and having a low serum total or free testosterone or androstenedione level was demonstrated. A low domain score for sexual responsiveness for women aged 45 years or older was associated with higher odds of having a serum dehydroepiandrosterone sulfate level below the 10th percentile for this age group (odds ratio [OR], 3.90; 95% confidence interval [CI], 1.54-9.81; P = .004). For women aged 18 to 44 years, having a low domain score for sexual desire (OR, 3.86; 95% CI, 1.27-11.67; P = .02), sexual arousal (OR, 6.39; 95% CI, 2.30-17.73; P<.001), and sexual responsiveness (OR, 6.59; 95% CI, 2.37-18.34; P<.001) was associated with having a dehydroepiandrosterone sulfate level below the 10th percentile. Conclusions  No single androgen level is predictive of low female sexual function, and the majority of women with low dehydroepiandrosterone sulfate levels did not have low sexual function.