Zhen Chen

BACKGROUND: Endometriosis (EMS) causes debilitating pain and reduces quality of life. Whether pelvic floor muscle training (PFMT) provides independent, additive benefits beyond standard postoperative hormonal suppression remains unknown. M…

BACKGROUND: While metabolic syndrome and obesity are established risk factors for infertility, previous studies have neglected age-specific analyses and nonlinear associations, particularly in women aged 20-45 years, a critical demographic …

In clinical drug development, two fundamental questions must be addressed: what is the success rate of drugs in clinical trial; how does such rate change over time. Here, a dynamic strategy for calculating clinical trial success rate (ClinS…

Osteosarcoma is an aggressive form of bone cancer and affects the health in children and adolescents. Although conventional treatment improves the osteosarcoma survival, some patients have metastasis and drug resistance, leading to a worse …

In many diagnostic accuracy studies, a priori orders may be available on multiple receiver operating characteristic curves. For example, being closer to delivery, fetal ultrasound measures in the third trimester should be no less accurate t…

Endometriosis is a commonly encountered gynecological disease in women, which seriously affects the life quality of patients. In Chinese traditional medicine, Four Agents Decoction is utilized in the clinical treatment of endometriosis for …

Acute pancreatitis is an inflammatory disorder of the pancreas associated with substantial morbidity and mortality, which is characterized by a rapid depletion of glutathione (GSH). Cysthionine-β-synthase (CBS) is a key coenzyme in GSH synt…

Endometriosis is a hormone-responsive gynecologic disease, signifying its connotations across a woman's life span. Previous studies suggested that endocrine disrupting chemicals were risk factors for endometriosis. Nevertheless, little is k…

IMPORTANCE: Dietary supplements marketed for male fertility commonly contain folic acid and zinc based on limited prior evidence for improving semen quality. However, no large-scale trial has examined the efficacy of this therapy for improv…

In application of diagnostic accuracy, it is possible that a priori information may exist regarding the test score distributions, either between different disease populations for a single test or between multiple correlated tests. Few have …

In analysis of diagnostic data with multiple tests, it is often the case that these tests are correlated. Modeling the correlation explicitly not only produces valid inference results but also enables borrowing of information. Motivated by …

BACKGROUND: Body mass index (BMI) and endometriosis have been inversely associated. To address gaps in this research, we examined associations among body composition, endometriosis, and physical activity. MATERIALS AND METHODS: Women from …

Published findings from the Longitudinal Investigation of Fertility and the Environment (LIFE) Study regarding the relation between environmental chemicals and couple fecundity, as measured by time-to-pregnancy (TTP), are reviewed with a pa…

STUDY QUESTION: Is sexual and/or physical abuse history associated with incident endometriosis diagnosis or other gynecologic disorders among premenopausal women undergoing diagnostic and/or therapeutic laparoscopy or laparotomy regardless …

BACKGROUND: Endometriosis is a gynecologic disease reported to be associated with infertility and, possibly, adverse pregnancy outcomes. While considerable research focuses on pregnancy outcomes following diagnosis and/or treatment, few dat…

In estimating ROC curves of multiple tests, some a priori constraints may exist, either between the healthy and diseased populations within a test or between tests within a population. In this paper, we proposed an integrated modeling appro…

Bisphenol A, benzophenone-type UV filters, and phthalates are chemicals in high production and use including in a range of personal care products. Exposure of humans to these chemicals has been shown to affect endocrine function. Although s…

OBJECTIVE: To determine agreement on endometriosis diagnosis between real-time laparoscopy and subsequent expert review of digital images, operative reports, magnetic resonance imaging (MRI), and histopathology, viewed sequentially. DESIGN…

STUDY QUESTION: What are the pain characteristics among women, with no prior endometriosis diagnosis, undergoing laparoscopy or laparotomy regardless of clinical indication? SUMMARY ANSWER: Women with surgically visualized endometriosis re…

OBJECTIVE: To assess benzophenone-type ultraviolet (UV) filter concentrations, chemicals used in sunscreen and personal care products, and semen endpoints. DESIGN: Cohort. SETTING: Not applicable. PATIENT(S): A total of 413 men provided …

Multiple trace elements have estrogen receptor activity, but the association of these elements with uterine leiomyoma has not been defined. A cohort of 473 women aged 18-44 undergoing surgery for benign gynecologic indications provided whol…

To evaluate the association between persistent organic pollutants (POPs) and uterine fibroids, we used previously collected data from a cohort of women aged 18-44 years undergoing laparoscopy or laparotomy at 14 participating hospital surgi…

In diagnostic studies without a gold standard, the assumption on the dependence structure of the multiple tests or raters plays an important role in model performance. In case of binary disease status, both conditional independence and cros…

OBJECTIVE: To explore the relation between bisphenol A and 14 phthalate metabolites and endometriosis. DESIGN: Matched cohort design. SETTING: Fourteen clinical centers. PATIENT(S): The operative cohort comprised 495 women undergoing lap…