Organophosphate flame retardants (OPFRs), including Tris (1,3-dichloro-isopropyl) phosphate (TDCPP), triphenyl phosphate (TPP), and isopropylated triphenyl phosphate (ITP), are increasingly used in ...consumer products because of the recent phase out of polybrominated diphenyl ether (PBDE) flame retardants. OPFRs have been widely detected in adults and have been linked to reproductive and endocrine changes in adult males. Carcinogenicity and damage to immunologic, neurologic and developmental systems have been observed in human cell lines. Young children are especially vulnerable to OPFR exposure, but little is known about exposure levels or exposure risk factors in this population. We examined parent-reported demographic and dietary survey data in relation to OPFR urinary metabolite concentrations in 15- to 18-month old toddlers (n = 41). OPFR metabolites were detected in 100% of subjects. The metabolite of TPP, diphenyl phosphate (DPP) was detected most commonly (100%), with TDCPP metabolite, bis(1,3-dichloro-2-propyl) phosphate (BDCPP), detected in 85–95% of samples, and ITP metabolite, monoisopropylphenyl phenyl phosphate (ip-DPP), detected in 81% of samples (n = 21). Toddlers of mothers earning <$10,000 annually had geometric mean DPP concentrations 66% higher (p = 0.05) than toddlers of mothers earning >$10,000/year (7.8 ng/mL, 95% CI 5.03, 12.11 and 4.69 ng/mL, 95% CI 3.65–6.04, respectively). While no dietary factors were significantly associated with OPFR metabolite concentrations, results suggested meat and fish consumption may be associated with higher DPP and BDCPP levels while increased dairy and fresh food consumption may be associated with lower DPP, BDCPP, and ip-DPP levels. Research with larger sample sizes and more detailed dietary data is required to confirm these preliminary findings.
•100% of toddler urine contained organophosphate flame retardants metabolites.•Maternal income impacted toddler diphenyl phosphate (DPP) concentrations.•Toddler dietary factors were below level of significance but showed trends.
Advances in medical technology and public health are changing the causes and patterns of pediatric mortality. To better inform health care planning for dying children, we sought to determine if an ...increasing proportion of pediatric deaths were attributable to an underlying complex chronic condition (CCC), what the typical age of CCC-associated deaths was, and whether this age was increasing.
Population-based retrospective cohort from 1980 to 1997, compiled from Washington State annual censuses and death certificates of children 0 to 18 years old.
For each of 9 categories of CCCs, the counts of death, mortality rates, and ages of death.
Nearly one-quarter of the 21 617 child deaths during this period were attributable to a CCC. Death rates for the sudden infant death syndrome (SIDS), CCCs, and all other causes each declined, but less so for CCCs. Among infants who died because of causes other than injury or SIDS, 31% of the remaining deaths were attributable to a CCC in 1980 and 41% by 1997; for deaths in children 1 year of age and older, CCCs were cited in 53% in 1980, versus 58% in 1997. The median age of death for all CCCs was 4 months 9 days, with substantial differences among CCCs. No overall change in the age of death between 1980 to 1997 was found (nonparametric trend test).
CCCs account for an increasing proportion of child deaths. The majority of these deaths occur during infancy, but the typical age varies by cause. These findings should help shape the design of support care services offered to children dying with chronic conditions and their families.
Regular sleep schedules are an important part of healthy sleep habits. Although television viewing is associated with altered sleep patterns and sleep disorders among children and adolescents, the ...effect of television viewing on the sleep patterns of infants and toddlers is not known.
To test the hypothesis that television viewing by infants and toddlers is associated with having irregular naptime and bedtime schedules.
We used data from the National Survey of Early Childhood Health, a nationally representative, cross-sectional study of the health and health care of children 4 to 35 months of age. Our main outcome measures were whether children had irregular naptime and bedtime schedules. Our main predictor was hours of television watched on a daily basis. We performed multivariate logistic regression analyses, adjusting for a variety of factors including demographic information, measures of maternal mental health, and measures of family interactions, to test the independent association of television viewing and irregular naptime and bedtime schedules.
Data were available for 2068 children. Thirty-four percent of all children had irregular naptime schedules, and 27% had irregular bedtime schedules. Mean hours of television viewing per day were as follows: 0.9 hours/day (95% confidence interval CI: 0.8-1.0 hours/day) for children <12 months of age, 1.6 hours/day (95% CI: 1.4-1.8 hours/day) for children 12 to 23 months of age, and 2.3 hours/day (95% CI: 2.1-2.5 hours/day) for children 24 to 35 months of age. In our logistic regression model, the number of hours of television watched per day was associated with both an irregular naptime schedule (odds ratio: 1.09; 95% CI: 1.01-1.18) and an irregular bedtime schedule (odds ratio: 1.13; 95% CI: 1.04-1.24).
Television viewing among infants and toddlers is associated with irregular sleep schedules. More research is warranted to determine whether this association is causal.
Observational studies in humans have found associations between overstimulation in infancy via excessive television viewing and subsequent deficits in cognition and attention. We developed and tested ...a mouse model of overstimulation whereby p10 mice were subjected to audio (70 db) and visual stimulation (flashing lights) for six hours per day for a total of 42 days. 10 days later cognition and behavior were tested using the following tests: Light Dark Latency, Elevated Plus Maze, Novel Object Recognition, and Barnes Maze. In all tests, overstimulated mice performed significantly worse compared to controls suggesting increased activity and risk taking, diminished short term memory, and decreased cognitive function. These findings suggest that excessive non-normative stimulation during critical periods of brain development can have demonstrable untoward effects on subsequent neurocognitive function.
Impact factor: a valid measure of journal quality? SAHA, Somnath; SAINT, Sanjay; CHRISTAKIS, Dimitri A
Journal of the Medical Library Association,
2003, 2003-Jan, 20030101, Letnik:
91, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Impact factor, an index based on the frequency with which a journal's articles are cited in scientific publications, is a putative marker of journal quality. However, empiric studies on impact ...factor's validity as an indicator of quality are lacking. The authors assessed the validity of impact factor as a measure of quality for general medical journals by testing its association with journal quality as rated by clinical practitioners and researchers.
We surveyed physicians specializing in internal medicine in the United States, randomly sampled from the American Medical Association's Physician Masterfile (practitioner group, n = 113) and from a list of graduates from a national postdoctoral training program in clinical and health services research (research group, n = 151). Respondents rated the quality of nine general medical journals, and we assessed the correlation between these ratings and the journals' impact factors.
The correlation between impact factor and physicians' ratings of journal quality was strong (r2 = 0.82, P = 0.001). The correlation was higher for the research group (r2 = 0.83, P = 0.001) than for the practitioner group (r2 = 0.62, P = 0.01).
Impact factor may be a reasonable indicator of quality for general medical journals.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Objective. The purpose of this study was to characterize response rates for mail surveys published in medical journals; to determine how the response rate among subjects who are typical targets of ...mail surveys varies; and to evaluate the contribution of several techniques used by investigators to enhance response rates.
Methods. One hundred seventy-eight manuscripts published in 1991, representing 321 distinct mail surveys, were abstracted to determine response rates and survey techniques. In a follow-up mail survey, 113 authors of these manuscripts provided supplementary information.
Results. The mean response rate among mail surveys published in medical journals is approximately 60%. However, response rates vary according to subject studied and techniques used. Published surveys of physicians have a mean response rate of only 54%, and those of non-physicians have a mean response rate of 68%. In addition, multivariable models suggest that written reminders provided with a copy of the instrument and telephone reminders are each associated with response rates about 13% higher than surveys that do not use these techniques. Other techniques, such as anonymity and financial incentives, are not associated with higher response rates.
Conclusions. Although several mail survey techniques are associated with higher response rates, response rates to published mail surveys tend to be moderate. However, a survey's response rate is at best an indirect indication of the extent of non-respondent bias. Investigators, journal editors, and readers should devote more attention to assessments of bias, and less to specific response rate thresholds.
Most parents believe childhood obesity is a problem for society, but not for their own children. We sought to understand whether parents' risk assessment was skewed by optimism, the tendency to ...overestimate one's chances of experiencing positive events.
We administered a national web-based survey to 502 parents of 5-12-year-old children. Parents reported the chances that (a) their child and (b) 'a typical child in their community' would be overweight or obese, and develop hypertension, heart disease, type 2 diabetes and depression in adulthood. Respondents self-reported demographic and health information, and we obtained demographic and health information about the typical child using zip code-level census and lifestyle data. We used regression models with fixed effects to evaluate whether optimism bias was present in parent predictions of children's future health outcomes.
Parents had 40 times lower adjusted odds (OR=0.025, P<0.001, 99% CI: 0.006, 0.100) of predicting that their child (versus a typical child) would be overweight or obese in adulthood. Of the 20% of parents who predicted their child would be overweight in adulthood, 93% predicted the typical child would also be overweight in adulthood. Controlling for health and demographic characteristics, parents estimated that their children's chances of developing obesity-related comorbidities would be 12-14 percentage points lower those that of a typical child.
Parent risk assessment is skewed by optimism, among other characteristics. More accurate risk perception could motivate parents to engage in behavior change.
The benefits of continuity of pediatric care remain controversial.
To determine whether there is an association between having a continuous relationship with a primary care pediatric provider and ...decreased risk of emergency department (ED) visitation and hospitalization.
Retrospective cohort study. Setting and Population. We used claims data from 46 097 pediatric patients enrolled at Group Health Cooperative, a large staff-model health maintenance organization, between January 1, 1993, and December 31, 1998, for our analysis. To be eligible, patients had to have been continuously enrolled for at least a 2-year period or since birth and to have made at least 4 visits to one of the Group Health Cooperative clinics. MAIN EXPOSURE VARIABLE: A continuity of care (COC) index that quantifies the degree to which a patient has experienced continuous care with a provider.
ED utilization and hospitalization.
Compared with children with the highest COC, children with medium continuity were more likely to have visited the ED (hazard ratio HR: 1.28 1.20-1.36) and more likely to be hospitalized (HR: 1.22 1.09-1.38). Children with the lowest COC were even more likely to have visited the ED (HR: 1.58 1.49-1.66) and to be hospitalized (HR: 1.54 1.33-1.75). These risks were even greater for children on Medicaid and those with asthma.
Lower continuity of primary care is associated with higher risk of ED utilization and hospitalization. Efforts to improve and maintain continuity may be warranted.
Cross-sectional research has suggested that television viewing may be associated with decreased attention spans in children. However, longitudinal data of early television exposure and subsequent ...attentional problems have been lacking. The objective of this study was to test the hypothesis that early television exposure (at ages 1 and 3) is associated with attentional problems at age 7.
We used the National Longitudinal Survey of Youth, a representative longitudinal data set. Our main outcome was the hyperactivity subscale of the Behavioral Problems Index determined on all participants at age 7. Children who were > or = 1.2 standard deviations above the mean were classified as having attentional problems. Our main predictor was hours of television watched daily at ages 1 and 3 years.
Data were available for 1278 children at age 1 and 1345 children at age 3. Ten percent of children had attentional problems at age 7. In a logistic regression model, hours of television viewed per day at both ages 1 and 3 was associated with attentional problems at age 7 (1.09 1.03-1.15 and 1.09 1.02-1.16), respectively.
Early television exposure is associated with attentional problems at age 7. Efforts to limit television viewing in early childhood may be warranted, and additional research is needed.
Childhood diarrhea accounts for substantial morbidity and mortality worldwide. Multiple studies in children have shown that Lactobacillus, administered orally, may have antidiarrheal properties. We ...conducted a meta-analysis of randomized, controlled studies to assess whether treatment with Lactobacillus improves clinical outcomes in children with acute infectious diarrhea.
Studies were sought in bibliographic databases of traditional biomedical as well as complementary and alternative medicine literature published from 1966 to 2000. Search terms were "competitive inhibition," "diarrhea," "gastroenteritis," "Lactobacillus," "probiotic," "rotavirus," and "yog(h)urt." We included studies that were adequately randomized, blinded, controlled trials in which the treatment group received Lactobacillus and the control group received an adequate placebo and that reported clinical outcome measures of diarrhea intensity. These inclusion criteria were applied by blind review and consensus. The original search yielded 26 studies, 9 of which met the criteria. Multiple observers independently extracted study characteristics and clinical outcomes. Data sufficient to perform meta-analysis of the effect of Lactobacillus on diarrhea duration and diarrhea frequency on day 2 were contained in 7 and 3 of the included studies, respectively.
Summary point estimates indicate a reduction in diarrhea duration of 0.7 days (95% confidence interval: 0.3-1.2 days) and a reduction in diarrhea frequency of 1.6 stools on day 2 of treatment (95% confidence interval: 0.7-2.6 fewer stools) in the participants who received Lactobacillus compared with those who received placebo. Details of treatment protocols varied among the studies. A preplanned subanalysis suggests a dose-effect relationship.
The results of this meta-analysis suggest that Lactobacillus is safe and effective as a treatment for children with acute infectious diarrhea.
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