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881.
Raul Zamora-Ros Valerie Cayssials Mazda Jenab Joseph A. Rothwell Veronika Fedirko Krasimira Aleksandrova Anne Tjønneland Cecilie Kyrø Kim Overvad Marie-Christine Boutron-Ruault Franck Carbonnel Yahya Mahamat-Saleh Rudolf Kaaks Tilman Kühn Heiner Boeing Antonia Trichopoulou Elissavet Valanou Effie Vasilopoulou Giovanna Masala Valeria Pala Salvatore Panico Rosario Tumino Fulvio Ricceri Elisabete Weiderpass Torkjel M. Sandanger Cristina Lasheras Antonio Agudo Maria-Jose Sánchez Pilar Amiano Carmen Navarro Eva Ardanaz Emily Sonestedt Bodil Ohlsson Lena Maria Nilsson Martin Rutegård Bas Bueno-de-Mesquita Kay-Thee Khaw Nicholas J. Wareham Kathryn Bradbury Heinz Freisling Isabelle Romieu Amanda J. Cross Paolo Vineis Augustin Scalbert 《European journal of epidemiology》2018,33(11):1063-1075
Polyphenols may play a chemopreventive role in colorectal cancer (CRC); however, epidemiological evidence supporting a role for intake of individual polyphenol classes, other than flavonoids is insufficient. We evaluated the association between dietary intakes of total and individual classes and subclasses of polyphenols and CRC risk and its main subsites, colon and rectum, within the European Prospective Investigation into Cancer and Nutrition (EPIC) study. The cohort included 476,160 men and women from 10 European countries. During a mean follow-up of 14 years, there were 5991 incident CRC cases, of which 3897 were in the colon and 2094 were in the rectum. Polyphenol intake was estimated using validated centre/country specific dietary questionnaires and the Phenol-Explorer database. In multivariable-adjusted Cox regression models, a doubling in total dietary polyphenol intake was not associated with CRC risk in women (HRlog2?=?1.06, 95% CI 0.99–1.14) or in men (HRlog2?=?0.97, 95% CI 0.90–1.05), respectively. Phenolic acid intake, highly correlated with coffee consumption, was inversely associated with colon cancer in men (HRlog2?=?0.91, 95% CI 0.85–0.97) and positively associated with rectal cancer in women (HRlog2?=?1.10, 95% CI 1.02–1.19); although associations did not exceed the Bonferroni threshold for significance. Intake of other polyphenol classes was not related to colorectal, colon or rectal cancer risks. Our study suggests a possible inverse association between phenolic acid intake and colon cancer risk in men and positive with rectal cancer risk in women. 相似文献
882.
How Many Imputations are Really Needed? Some Practical Clarifications of Multiple Imputation Theory 总被引:1,自引:0,他引:1
Multiple imputation (MI) and full information maximum likelihood (FIML) are the two most common approaches to missing data
analysis. In theory, MI and FIML are equivalent when identical models are tested using the same variables, and when m, the number of imputations performed with MI, approaches infinity. However, it is important to know how many imputations
are necessary before MI and FIML are sufficiently equivalent in ways that are important to prevention scientists. MI theory
suggests that small values of m, even on the order of three to five imputations, yield excellent results. Previous guidelines for sufficient m are based on relative efficiency, which involves the fraction of missing information (γ) for the parameter being estimated, and m. In the present study, we used a Monte Carlo simulation to test MI models across several scenarios in which γ and m were varied. Standard errors and p-values for the regression coefficient of interest varied as a function of m, but not at the same rate as relative efficiency. Most importantly, statistical power for small effect sizes diminished as
m became smaller, and the rate of this power falloff was much greater than predicted by changes in relative efficiency. Based
our findings, we recommend that researchers using MI should perform many more imputations than previously considered sufficient.
These recommendations are based on γ, and take into consideration one’s tolerance for a preventable power falloff (compared to FIML) due to using too few imputations. 相似文献
883.
Halileh S Abu-Rmeileh N Watt G Spencer N Gordon N 《Maternal and child health journal》2008,12(5):606-612
The objective of this cross sectional study is to look at determinants of birth weight and their association with the gender
of the baby in 2,795 full term children living in the occupied Palestinian territory, derived from a stratified random sample
of 2,994 households in the West Bank and 2,234 households in the Gaza Strip. The response rate was 85%. Multivariable analysis
using analysis of variance for mixed models showed that sex and birth order, maternal age and education and to a lesser extent
region were determinants of birth weight for all children. The effect of maternal education on birth weight differed for female
and male infants, tending to be relatively unchanged for male infants and with mean birth weights increasing with maternal
education in female infants. The effect of birth order differed by maternal age, with mean birth weight increasing with maternal
age for first and second births; but being unaffected by maternal age for infants of birth order greater than two. We conclude
that birth weight is influenced by common biological determinants across cultures, but is also influenced by social, ethnic,
and environmental factors that are culture specific, of which some might be gender related.
相似文献
Samia HalilehEmail: |
884.
Su M Liu M Tian DP Li XY Zhang GH Yang HL Fan X Huang HH Gao YX 《European journal of epidemiology》2007,22(1):43-48
The purpose of our study was to investigate the temporal malignant tumor incidence rates among the 70,000 residents at the
relatively isolated Nanao Island in South China Sea. The data on all malignant tumor cases from Nanao Cancer Registry during
1995–2004 were coded, computerized, and analyzed using the software SPSS10.0. The tumor incident cases, crude incident rate,
age-standardized incidence rate, their sex distribution and temporal trend were assessed. A total of 1450 new cancer cases
(990 males and 460 females) were identified. The annual average age-standardized incidence rate (ASR) of malignant tumors
was 208.18/100,000. The age-standardized incidence rate of the ten leading cancers in both sexes combined per 100,000 population
were 74.47 for esophageal cancer (EC), 34.81 for cardiac cancer (CC), 25.66 for liver cancer, 26.01 for lung cancer, 18.52
for stomach cancer, 4.45 for nasopharyngeal cancer, 3.91 for breast cancer, 2.53 for colon/rectum cancer, 2.45 for bladder
cancer and 1.92 for pancreatic cancer. These ten types of cancers make up to 93% of all cancer cases, with EC and CC being
the most prevalent and making up 52% of the total cases. The incidence rates of esophagus, liver, lung, breast, nasopharyngeal,
and colon/rectum cancers showed increasing trends during the period from 1995 to 2004 in Nanao Island. Astounding the EC ASR
were 72–150/100,000 among male and 26–64/100,000 among female in Nanao Island during 1995–2004. The EC incidence rate in Nanao
population is among the highest across the world, which suggests that there are potential genetic and/or environmental factors
affecting this particular population. 相似文献
885.
Annaheim B Rehm J Neuenschwander M Gmel G 《International journal of public health》2007,52(4):233-241
Summary Quitting hash. The readiness for behaviour change among cannabis users in Switzerland.
Objectives: The study aims to identify factors that are associated with the willingness of adolescents and young adults to modify their
cannabis use. It is hypothesized that frequency of use, cannabis-related problems and age of onset are associated with their
willingness to change.
Methods: In 2004, a survey on cannabis use was conducted among 13 to 29 year-olds living in Switzerland. Of the 5025 participants 593
had taken cannabis during the past six months. They were then asked about their willingness to change. Three groups of users
were compared: those not willing to change, those considering change, and those determined to change. Pearson Chi-square-tests
and logistic regressions were performed to test the hypotheses.
Results: Experience of problems motivates users to start thinking about changing their behavior. Frequent use and early onset are associated
with young people not making the transition from considering changing behavior to resolving to do so.
Conclusions: The need to perceive problematic use as a first step towards change and the inhibiting effect of dependencerelated factors
on the transition from consideration to determination calls for tailored intervention approaches that are matched to the willingness
to change.
Eingereicht: 10. Dezember 2005; überarbeitet: 13. September 2006; Angenommen: 6. M?rz 2007 相似文献
886.
Feng Xie Shu-Chuen Li Ron Goeree Jean-Eric Tarride Daria O’Reilly Ngai-Nung Lo Seng-Jin Yeo Kuang-Ying Yang Julian Thumboo 《Quality of life research》2008,17(4):595-601
Objective Our aim was to cross-culturally validate Chinese Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) in
patients with knee osteoarthritis (OA) scheduled for total knee replacement in Singapore.
Methods Chinese WOMAC was translated from the original English version following standard guidelines. Patients were asked to complete
a questionnaire containing the WOMAC (twice within 6 days), the Short Form 36 (SF-36), and the EuroQoL EQ-5D. Reliability
was assessed using Cronbach’s alpha and intraclass correlation coefficients (ICC), dimensionality using item-to-domain correlations
and factor analyses. Convergent and discriminant construct validity was assessed using six each a priori hypotheses.
Results Chinese WOMAC was well accepted by the patients in the pilot test. The Chinese and English versions were therefore administered
to a consecutive sample of 131 Chinese- and 127 English-speaking subjects, respectively, with knee OA. Cronbach’s alpha exceeded
0.7 for all domains except for Chinese pain domain, whereas the ICC exceeded 0.7 for all domains. Hypothesized item-to-domain
correlations were observed for all items except for four items in Chinese physical function domain. The factor analyses yielded
seven and five factors with eigenvalues of more than 1.0 in the Chinese and English versions, respectively. A total of 10/12
a priori construct validity hypotheses were satisfied for the Chinese version. Weak correlations between WOMAC pain and SF-36
bodily pain and moderate correlation between WOMAC pain and EQ-5D anxiety/depression were observed.
Conclusions Chinese WOMAC was well accepted and demonstrated acceptable psychometric properties in Singaporean patients with severe knee
OA. 相似文献
887.
Hugenholtz NI Schaafsma FG Nieuwenhuijsen K van Dijk FJ 《International archives of occupational and environmental health》2008,82(1):107-115
OBJECTIVE: An intervention existing of an evidence-based medicine (EBM) course in combination with case method learning sessions (CMLSs) was designed to enhance the professional performance, self-efficacy and job satisfaction of occupational physicians. METHODS: A cluster randomized controlled trial was set up and data were collected through questionnaires at baseline (T0), directly after the intervention (T1) and 7 months after baseline (T2). The data of the intervention group [T0 (n = 49), T1 (n = 31), T2 (n = 29)] and control group [T0 (n = 49), T1 (n = 28), T2 (n = 28)] were analysed in mixed model analyses. Mean scores of the perceived value of the CMLS were calculated in the intervention group. RESULTS: The overall effect of the intervention over time comparing the intervention with the control group was statistically significant for professional performance (p < 0.001). Job satisfaction and self-efficacy changes were small and not statistically significant between the groups. The perceived value of the CMLS to gain new insights and to improve the quality of their performance increased with the number of sessions followed. CONCLUSION: An EBM course in combination with case method learning sessions is perceived as valuable and offers evidence to enhance the professional performance of occupational physicians. However, it does not seem to influence their self-efficacy and job satisfaction. 相似文献
888.
Background
Data on the effect of contraceptive methods, other than the condom, on HIV acquisition is not clear. The aim of this study was to describe hormonal contraceptive use, sexual behaviour and HIV prevalence among women in Cameroon in order to provide baseline information for future analytical studies. 相似文献889.
Annabelle M Wilson Anthea M Magarey Nadia Mastersson 《The international journal of behavioral nutrition and physical activity》2008,5(1):5
Background
Food behaviours, attitudes, environments and knowledge are relevant to professionals in childhood obesity prevention, as are dietary patterns which promote positive energy balance. There is a lack of valid and reliable tools to measure these parameters. The aim of this study was to determine the reliability and relative validity of a child nutrition questionnaire assessing all of these parameters, used in the evaluation of a community-based childhood obesity prevention project. 相似文献890.
Nur Najihah Izzati Mat Rani Xiang Yi Chen Zahraa M.Al-Zubaidi Hanisah Azhari Tzar Mohd Nizam Khaitir Pei Yuen Ng Fhataheya Buang Geok Chin Tan Yin Ping Wong Mazlina Mohd Said Adeel Masood Butt Azmy A.Hamid Mohd Cairul Iqbal Mohd Amin 《Asian Journal of Pharmaceutical Sciences》2022,17(1):102-119
This study focused on the encapsulation of vancomycin(VAN) into liposomes coated with a red blood cell membrane with a targeting ligand, daptomycin–polyethylene glycol–1,2-distearoyl-sn-glycero-3-phosphoethanolamine, formed by conjugation of DAPT and Nhydroxysuccinimidyl-polyethylene glycol-1,2-distearoyl-sn-glycero-3-phosphoethanolamine.This formulation is capable of providing controlled and targeted drug delivery to the bacterial cytoplasm. We performed MALDI-TOF, NMR and FTIR analyses to conf... 相似文献