Using sexually transmitted infection biomarkers to validate reporting of sexual behavior within a randomized, experimental evaluation of interviewing methods

This paper examines the reporting of sexual and other risk behaviors within a randomized experiment using a computerized versus face-to-face interview mode. Biomarkers for sexually transmitted infection (STI) were used to validate self-reported behavior by interview mode. As part of a parent study evaluating home versus clinic screening and diagnosis for STIs, 818 women aged 18-40 years were recruited in 2004 at or near a primary care clinic in S?o Paulo, Brazil, and were randomized to a face-to-face interview or audio computer-assisted self-interviewing. Ninety-six percent of participants were tested for chlamydia, gonorrhea, and trichomoniasis. Reporting of STI risk behavior was consistently higher with the computerized mode of interview. Stronger associations between risk behaviors and STI were found with the computerized interview after controlling for sociodemographic factors. These results were obtained by using logistic regression approaches, as well as statistical methods that address potential residual confounding and covariate endogeneity. Furthermore, STI-positive participants were more likely than STI-negative participants to underreport risk behavior in the face-to-face interview. Results strongly suggest that computerized interviewing provides more accurate and reliable behavioral data. The analyses also confirm the benefits of using data on prevalent STIs for externally validating behavioral reporting.     

Comparison of the effectiveness of radiotherapy with photons, protons and carbon-ions for non-small cell lung cancer: A meta-analysis

Purpose: To provide a comparison between radiotherapy with photons, protons and carbon-ions in the treatment of Non-Small-Cell Lung Cancer (NSCLC), performing a meta-analysis of observational studies. Methods: Eligible studies on conventional radiotherapy (CRT), stereotactic radiotherapy (SBRT), concurrent chemoradiation (CCR), proton therapy and carbon-ion therapy were searched through a systematic review. To obtain pooled estimates of 2- and 5-year disease-specific and overall survival and the occurrence of severe adverse events for each treatment modality, a random effects meta-analysis was carried out. Pooled estimates were corrected for effect modifiers. Results: Corrected pooled estimates for 2-year overall survival in stage I inoperable NSCLC ranged from 53% for CRT to 74% for carbon-ion therapy. Five-year overall survival for CRT (20%) was statistically significantly lower than that for SBRT (42%), proton therapy (40%) and carbon-ion therapy (42%). However, caution is warranted due to the limited number of patients and limited length of follow-up of the particle studies. Conclusion: Survival rates for particle therapy were higher than those for CRT, but similar to SBRT in stage I inoperable NSCLC. Particle therapy may be more beneficial in stage III NSCLC, especially in reducing adverse events.     

18FDG-PET-CT in the follow-up of non-small cell lung cancer patients after radical radiotherapy with or without chemotherapy: An economic evaluation

BackgroundThe optimal follow-up strategy of non-small cell lung cancer (NSCLC) patients after curative intent therapy is still not established. In a recent prospective study with 100 patients, we showed that a FDG-PET-CT 3 months after radiotherapy (RT) could identify progression amenable for curative treatment in 2% (95% confidence interval (CI): 1–7%) of patients, who were all asymptomatic. Here, we report on the economic evaluation of this study.Patients and methodsA decision-analytic Markov model was developed in which the long-term cost-effectiveness of 3 follow-up strategies was modelled with different imaging methods 3 months after therapy: a PET-CT scan; a chest CT scan; and conventional follow-up with a chest X-ray. A probabilistic sensitivity analysis was performed to account for uncertainty. Because the results of the prospective study indicated that the advantage seems to be confined to asymptomatic patients, we additionally examined a strategy where a PET-CT was applied only in the subgroup of asymptomatic patients. Cost-effectiveness of the different follow-up strategies was expressed in incremental cost-effectiveness ratios (ICERs), calculating the incremental costs per quality adjusted life year (QALY) gained.ResultsBoth PET-CT- and CT-based follow-up were more costly but also more effective than conventional follow-up. CT-based follow-up was only slightly more effective than conventional follow-up, resulting in an incremental cost-effectiveness ratio (ICER) of € 264.033 per QALY gained. For PET-CT-based follow-up, the ICER was € 69.086 per QALY gained compared to conventional follow-up. The strategy in which a PET-CT was only performed in the asymptomatic subgroup resulted in an ICER of € 42.265 per QALY gained as opposed to conventional follow-up. With this strategy, given a ceiling ratio of € 80.000, PET-CT-based follow-up had the highest probability of being cost-effective (73%).ConclusionsThis economic evaluation shows that a PET-CT scan 3 months after (chemo)radiotherapy with curative intent is a potentially cost-effective follow-up method, and is more cost-effective than CT alone. Applying a PET-CT scan only in asymptomatic patients is probably as effective and more cost-effective. It is worthwhile to perform additional research to reduce uncertainty regarding the decision concerning imaging in the follow-up of NSCLC.     

Dietary acrylamide intake and estrogen and progesterone receptor-defined postmenopausal breast cancer risk

Acrylamide, a potential human carcinogen, has been discovered in a variety of heat-treated carbohydrate-rich food products. Previously, dietary acrylamide intake was shown to be associated with endocrine-related cancers in humans. We assessed the association between dietary acrylamide intake and risk of postmenopausal breast cancer stratified by estrogen and progesterone receptor status. This study was embedded within the Netherlands Cohort Study on diet and cancer, which was initiated in 1986 enrolling 62,573 women aged 55–69 years at baseline. After 13.3 years of follow-up, 2225 incident breast cancer cases were ascertained, with hormone receptor status information for 43%. Cox proportional hazards analysis was applied to determine hazard ratios in quintiles of dietary acrylamide intake stratifying on estrogen receptor (ER) and progesterone receptor (PR) and smoking status. No association was observed for overall breast cancer or receptor-negative breast cancer risk, irrespective of smoking status. A statistically non-significantly increased risk of ER positive, PR positive and joint receptor-positive breast cancer was found in never-smoking women. The multivariable-adjusted hazard ratios were 1.31 (95% CI: 0.87–1.97, P _trend = 0.26) for ER+, 1.47 (0.86–2.51, P _trend = 0.14) for PR+, and 1.43 (0.83–2.46, P _trend = 0.16) for ER+PR+, when comparing women in the highest quintile of acrylamide intake (median 36.8 μg/day) to women in the lowest (median 9.5 μg/day). This study showed some indications of a positive association between dietary acrylamide intake and receptor-positive breast cancer risk in postmenopausal never-smoking women. Further studies are needed to confirm or refute our observations.     

"Expectant Parents": Study protocol of a longitudinal study concerning prenatal (risk) factors and postnatal infant development, parenting, and parent-infant relationships

ABSTRACT: BACKGROUND: While the importance of the infant-parent relationship from the child's perspective is acknowledged worldwide, there is still a lack of knowledge about predictors and long-term benefits or consequences of the quality of parent-infant relationships from the parent's perspective. The purpose of this prospective study is to investigate the quality of parent-infant relationships from parents' perspectives, both in the prenatal and postpartum period. This study therefore focuses on prenatal (risk) factors that may influence the quality of pre- and postnatal bonding, the transition to parenthood, and bonding as a process within families with young children. In contrast to most research concerning pregnancy and infant development, not only the roles and experiences of mothers during pregnancy and the first two years of infants' lives are studied, but also those of fathers. Methods/design The present study is a prospective longitudinal cohort study, in which pregnant women (N = 466) and their partners (N = 319) are followed from 15 weeks gestation until their child is 24 months old. During pregnancy, midwives register the presence of prenatal risk factors and provide obstetric information after the child's birth. Parental characteristics are investigated using self- report questionnaires at 15, 26, and 36 weeks gestational age and at four, six, 12, and 24 months postpartum. At 26 weeks of pregnancy and at six months postpartum, parents are interviewed concerning their representations of the (unborn) child. At six months postpartum, the mother-child interaction is observed in several situations within the home setting. When children are four, six, 12, and 24 months old, parents also complete questionnaires concerning the child's (social-emotional) development and the parent-child relationship. Additionally, at 12 months information about the child's physical development and well-being during the first year of life is retrieved from National Health Care Centres. DISCUSSION: The results of this study may contribute to early identification of families at risk for adverse parent-infant relationships, infant development, or parenting. Thereby this study will be relevant for the development of policy, practice, and theory concerning infant mental health.     

First-trimester placental vascular development in multiparous women differs from that in nulliparous women

Objective: Multiparas differ from nulliparas by delivering larger babies with larger placentas and by having a lower risk of developing placental syndromes. We postulate that these differences result from a different initial course of placental vascular development.

Study design: We measured placental flow index (FI), vascularization index (VI) and placental volume by 3D power Doppler and obtained blood samples at 8, 10 and 12 weeks pregnancy in 34 healthy nulliparous and 16 multiparous women with an uneventful pregnancy.

Results: Between 8 and 12 weeks multiparas differed from nulliparas in a more rapid initial rise in FI, a higher angiopoietin-2 (ang2) level at eight weeks and no decline in the VEGF/sVEGF-R ratio. Nevertheless, at 12 weeks the FI and placental volume were indistinguishable between both study groups.

Conclusions: These results combining serially measured placental vascularization, placental volume and circulating angiogenetic factors show initial differences in placental development, that howeve, did not maintain till the end of first trimester. The results support the concept that early placental vascular development differs between nulliparas and multiparas. Nevertheless, it is unclear whether these differences contribute to the development later on in pregnancy of intergroup differences in birthweight and incidence of placental syndromes.