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author:("Lu, taiji")
1.  Informal care and health behaviors among elderly people with chronic diseases 
The mechanism by which social relationships influence health can be interpreted as a social network regulating one’s health behaviors. Based on the hypothesis that relatives, friends, or neighbors are sources of social support and may monitor one’s health behaviors, researchers have gotten significant and consistent results that a social network can regulate health behaviors. However, few empirical studies have been conducted to examine the role of informal care in the regulation of health behaviors, especially for elderly individuals with chronic diseases that can be controlled by healthy behaviors. This paper researched the effects of informal care on health behaviors—smoking control, dietetic regulation, weight control, and maintenance of exercise—among elderly patients with chronic diseases in China who are facing the challenge of aging.
We used the propensity score matching method to control the impacts of a very rich set of family and individual characteristics. The 2011–2012 national baseline data of the China Health and Retirement Longitudinal Study (CHARLS) was used.
Our findings showed that informal care could significantly help improve the health behaviors of elderly people. Informal care could improve the compliance of smoking control and dietetic regulation significantly. Elderly people with informal care smoked less and consumed more meals per day. For weight control, informal care helped decrease the possibility of weight gain of elderly people, but its impacts were not significant for BMI and weight loss. Last, for the elders, informal care could only help increase the probability of walking exercise; however, there was no significant result for moderate exercise.
Findings from this study highlight the importance of informal care among elderly people. Our results appeal to policy makers who aim to control chronic diseases that they should take informal care into account and provide appropriate policies to meet the demand of informal care for elderly people.
Electronic supplementary material
The online version of this article (10.1186/s41043-017-0117-x) contains supplementary material, which is available to authorized users.
PMCID: PMC5717826  PMID: 29208036
Informal care; Health behaviors; Chronic diseases; Elderly people; CHARLS; Propensity score matching method
2.  Social Structure and Depression in TrevorSpace 
We discover patterns related to depression in the social graph of an online community of approximately 20,000 lesbian, gay, and bisexual, transgender, and questioning youth. With survey data on fewer than two hundred community members and the network graph of the entire community (which is completely anonymous except for the survey responses), we detected statistically significant correlations between a number of graph properties and those TrevorSpace users showing a higher likelihood of depression, according to the Patient Healthcare Questionnaire-9, a standard instrument for estimating depression. Our results suggest that those who are less depressed are more deeply integrated into the social fabric of TrevorSpace than those who are more depressed. Our techniques may apply to other hard-to-reach online communities, like gay men on Facebook, where obtaining detailed information about individuals is difficult or expensive, but obtaining the social graph is not.
PMCID: PMC5421990
LGBT youth; social network analysis; social media; H.5.m. Information Interfaces and Presentation (e.g. HCI): Group and Organization Interfaces
3.  Exploring the impact of word-of-mouth about Physicians’ service quality on patient choice based on online health communities 
Health care service is a high-credence service and patients may face difficulties ascertaining service quality in order to make choices about their available treatment options. Online health communities (OHCs) provide a convenient channel for patients to search for physicians’ information, such as Word-of-Mouth (WOM), particularly on physicians’ service quality evaluated by other patients. Existing studies from other service domains have proved that WOM impacts consumer choice. However, how patients make a choice based on physicians’ WOM has not been studied, particularly with reference to different patient characteristics and by using real data.
One thousand eight hundred fifty three physicians’ real data were collected from a Chinese online health community. The data were analyzed using ordinary least squares (OLS) method.
The study found that functional quality negatively moderated the relationship between technical quality and patient choice, and disease risk moderated the relationship between physicians’ service quality and patient choice.
Our study recommends that hospital managers need to consider the roles of both technical quality and functional quality seriously. Physicians should improve their medical skills and bedside manners based on the severity and type of disease to provide better service.
PMCID: PMC5124243  PMID: 27888834
Online health communities; Word-of-mouth; Service quality; Technical quality; Functional quality; Patient choice; Disease risk
4.  Prevalence, Correlates, and Symptom Profiles of Depression among Men with a History of Military Service 
The purpose of this study was to examine the prevalence, correlates, and symptom profiles of depressive disorders in men with a history of military service.
Data was obtained from the 2006 Behavioral Risk Factor Surveillance System (BRFSS) survey. Multivariable logistic regressions were used to identify correlates of lifetime and current depression. Regularly occurring symptom profiles were identified via cluster analysis.
Prevalence of lifetime and current depression was similar in men with and without a history of military service. Lifetime diagnosis was positively associated with younger age and negatively associated with black minority status, married or cohabitation, and self-reported good health. Current depression was positively associated with other minority status (non-Hispanic non-black) and negatively associated with older age, some college, being in a relationship, and self-reported good health. A cluster of younger men who experience significant depressive symptoms but may not report depressed mood or anhedonia was identified.
Depression is as prevalent in men with a history of military service as it is in men without a history. Research should examine subpopulations of men with a history of military service in which depression may be more prevalent or burdensome. Younger men with significant depressive symptoms may be missed by standard depression screens and still be at elevated risk for negative outcomes associated with depressive disorders.
PMCID: PMC5064430  PMID: 20652680
Depression; Prevalence; Military Personnel; Veterans
5.  Associations Between the Department of Veterans Affairs' Suicide Prevention Campaign and Calls to Related Crisis Lines 
Public Health Reports  2014;129(6):516-525.
The Transit Authority Suicide Prevention (TASP) campaign was launched by the Department of Veterans Affairs (VA) in a limited number of U.S. cities to promote the use of crisis lines among veterans of military service.
We obtained the daily number of calls to the VCL and National Suicide Prevention Lifeline (NSPL) for six implementation cities (where the campaign was active) and four control cities (where there was no TASP campaign messaging) for a 14-month period. To identify changes in call volume associated with campaign implementation, VCL and NSPL daily call counts for three time periods of equal length (pre-campaign, during campaign, and post-campaign) were modeled using a Poisson log-linear regression with inference based on the generalized estimating equations.
Statistically significant increases in calls to both the VCL and the NSPL were reported during the TASP campaign in implementation cities, but were not reported in control cities during or following the campaign. Secondary outcome measures were also reported for the VCL and included the percentage of callers who are veterans, and calls resulting in a rescue during the study period.
Results from this study reveal some promise for suicide prevention messaging to promote the use of telephone crisis services and contribute to an emerging area of research examining the effects of campaigns on help seeking.
PMCID: PMC4187294  PMID: 25364053
6.  Parent and Child Psychopathology and Suicide Attempts among Children of Parents with Alcohol Use Disorder 
Parents with psychopathology such as alcohol use disorder (AUD) that confers risk for suicide attempt (SA) may have children who are more likely to develop such psychopathology and to attempt suicide, suggesting that risk may be “transmitted” from parents to children. We examined this phenomenon during the transition from childhood to adolescence, when risk for SA increases dramatically. A cohort of 418 children were examined at average age 9.4 (range 7–14) years at enrollment (Time 1, childhood) and approximately five years later, prior to reaching age 18 (Time 2, adolescence). One or both biological parents, oversampled for AUD, were also interviewed. Structural equation models (SEM) examined father-child, mother-child, and either/both parent-child associations. The primary outcome was SA over follow-up among offspring, assessed at Time 2. As hypothesized, parental antisocial personality disorder predicted conduct disorder symptoms in offspring both during childhood and adolescence (parent-child model, father-child model) and maternal AUD predicted conduct disorder symptoms during childhood (mother-child model). However, we did not find evidence to support transmission of depression from parents to offspring either during childhood or adolescence, and parent psychopathology did not show statistically significant associations with SA during adolescence. In conclusion, we conducted a rare study of parent-to-child “transmission” of risk for SA that used a prospective research design, included diagnostic interviews with both parents and offspring, and examined the transition from childhood to adolescence, and the first such study in children of parents with AUD. Results provided mixed support for hypothesized parent-child associations.
PMCID: PMC4059391  PMID: 24716789
adolescent; parent; suicide attempt; alcohol use disorder; risk factor
7.  Log-transformation and its implications for data analysis 
Shanghai Archives of Psychiatry  2014;26(2):105-109.
The log-transformation is widely used in biomedical and psychosocial research to deal with skewed data. This paper highlights serious problems in this classic approach for dealing with skewed data. Despite the common belief that the log transformation can decrease the variability of data and make data conform more closely to the normal distribution, this is usually not the case. Moreover, the results of standard statistical tests performed on log-transformed data are often not relevant for the original, non-transformed data.We demonstrate these problems by presenting examples that use simulated data. We conclude that if used at all, data transformations must be applied very cautiously. We recommend that in most circumstances researchers abandon these traditional methods of dealing with skewed data and, instead, use newer analytic methods that are not dependent on the distribution the data, such as generalized estimating equations (GEE).
PMCID: PMC4120293  PMID: 25092958
hypothesis testing; outliners; lon-normal distribution; normal distribution; skewness
8.  Prevalence and natural course of late-life depression in China primary care: A population based study from an urban community 
Journal of affective disorders  2012;141(1):86-93.
Primary care is the most promising venue for the management of late-life depression in China. The current study was designed to establish the prevalence of major depressive disorder among older adults in primary care, and to examine the correlates, and the natural course of late-life depression over a year.
A sample of 1275 adults aged over 60 years was recruited from a primary care clinic in urban China for screening with PHQ-9, and 262 participants stratified by PHQ-9 score were interviewed to collect the presence of major depressive disorder (MDD), the availability of social support, and physical health and functional status. Participants were followed up for 12 months at 3-month intervals.
The estimated prevalence of MDD was 11.3% with the SCID interview. Increasing age, female gender, and lower educational level, living alone, low support from family, high medical illness burden, and impairment of daily function were significantly associated with MDD in later life. Less than 1% of these patients received treatments. More than 60% of patients with MDD at baseline remained depressed throughout the 12 month follow-up period; and only 3 patients had been treated during the 12-month follow-up.
The correlates of late-life depression observed here may not necessarily serve as risk factors guiding the development of future prevention strategies.
In an urban Chinese primary care setting, late-life depression was found to be a common condition. Few patients with MDD received treatment for their condition, and the majority remained depressed over the following year.
PMCID: PMC3566241  PMID: 22464006
Late-life depression; Chinese primary care; Prevalence; Correlates; Natural course
9.  Power analysis for cross-sectional and longitudinal study designs 
Shanghai Archives of Psychiatry  2013;25(4):259-262.
PMCID: PMC4054560  PMID: 24991165
10.  Predictors of Treatment Outcomes among Depressed Women with Childhood Sexual Abuse Histories 
Depression and Anxiety  2012;29(6):479-486.
A notable portion (21%) of female patients receiving treatment for depression in community mental health centers (CMHC) has childhood sexual abuse (CSA) histories. Treatment outcomes in this population are heterogeneous; identifying factors associated with differential outcomes could inform treatment development. This exploratory study begins to address the gap in what is known about predictors of treatment outcomes among depressed women with sexual abuse histories.
Seventy women with major depressive disorder and CSA histories in a CMHC were randomly assigned to Interpersonal Psychotherapy (n = 37) or usual care (n = 33). Using generalized estimating equations, we examined four pre-treatment predictor domains (i.e., sociodemographic characteristics, clinical features, social and physical functioning, and trauma features) potentially related to depression treatment outcomes.
Among sociodemographic characteristics, Black race/ethnicity, public assistance income, and unemployment were associated with less depressive symptom reduction over the course of treatment. Two clinical features, chronic depression and borderline personality disorder, were also related to less reduction in depressive symptoms across the treatment period.
Our results demonstrate the clinical relevance of attending to predictors of depressed women with CSA histories being treated in public sector mental health centers. Particular sociodemographic characteristics and clinical features among these women may be significant indicators of risk for relatively poorer treatment outcomes.
PMCID: PMC3383394  PMID: 22570264
adult survivors of child abuse; major depressive disorder; treatment resistance; community mental health services; IPT/interpersonal psychotherapy
11.  Effect of Thin Prep® imaging system on laboratory rate and relative sensitivity of atypical squamous cells, high-grade squamous intraepithelial lesion not excluded and high-grade squamous intraepithelial lesion interpretations 
CytoJournal  2013;10:6.
Automated screening of Thin Prep® Papanicolaou Tests has become increasingly common in clinical practice. Increased productivity has initiated laboratory use of the Thin Prep® Imaging System (TIS). Increased sensitivity is a potential additional benefit of TIS. Published studies have shown an increase in discovery of dysplastic cells. This study evaluates the effect of TIS on the incidence of atypical squamous cells high-grade squamous intraepithelial lesion not excluded (ASC-H) and high-grade squamous intraepithelial lesion (HGSIL) results on Thin Prep® Pap Tests by comparing TIS-assisted and manual screening findings and the diagnoses on subsequent follow-up in a screening population over a 1-year time period.
Materials and Methods:
A compilation of all ASC-H and HGSIL cases was prepared by conducting a computerized search over a 1-year period (7/06-6/07). The accumulated cases include Thin Prep Pap tests that were both TIS and manually screened. Follow-up results of cytologic and histologic cervical specimens were obtained for a time period extending to 2010. Interpretation utilizing TIS was in place 10 months prior to the study's initiation.
During the study period 70,522 Pap tests were performed in our laboratory. One third (33%) of Pap tests were screened with assistance of TIS. Manual screening was performed on 47,380 Pap tests of which 153 (0.32%) were interpreted as ASC-H and 164 (0.35%) were interpreted as HGSIL. During the same time period automated screening (TIS) was performed on 23,111 Pap tests. Interpretation of 62 (0.27%) cases provided an ASC-H result, while 71 (0.31%) were HGSIL. Follow-up cervical dysplasia by colposcopic biopsy and cone biopsy was distributed proportionally between TIS and manual screening for both ASC-H and HGSIL categories. Cervical intraepithelial neoplasia (CIN II/III) was identified on follow-up biopsy of 41% TIS cases and 45% manually screened cases for ASC-H. In the HGSIL subset 71% of TIS cases and 69% manually screened cases showed CIN II/III on follow-up. TIS was 26% less sensitive relative to manual screening for ASC-H cases and 3% less sensitive for HGSIL.
The similar rate of detection using TIS with an equal percentage of histologic correlation for ASC-H and HGSIL lesions on follow-up histology suggests patients screened by the TIS method are being sent for appropriate follow-up surveillance and treatment. A high-grade or possible high-grade lesion is as likely to be detected by TIS as by a manual screen. The similarities in relative sensitivity and specificity in a direct comparison between manual and TIS screening methodologies indicate that TIS compared to manual screening does not affect detection in patients with high-grade cervical lesions.
PMCID: PMC3623450  PMID: 23599725
Atypical squamous cells; automated screening; cannot exclude high-grade; high-grade squamous intraepithelial lesion; Thin Prep® Imaging System
12.  On Fitting Generalized Linear Mixed-effects Models for Binary Responses using Different Statistical Packages 
Statistics in medicine  2011;30(20):2562-2572.
The generalized linear mixed-effects model (GLMM) is a popular paradigm to extend models for cross-sectional data to a longitudinal setting. When applied to modeling binary responses, different software packages and even different procedures within a package may give quite different results. In this report, we describe the statistical approaches that underlie these different procedures and discuss their strengths and weaknesses when applied to fit correlated binary responses. We then illustrate these considerations by applying these procedures implemented in some popular software packages to simulated and real study data. Our simulation results indicate a lack of reliability for most of the procedures considered, which carries significant implications for applying such popular software packages in practice.
PMCID: PMC3175267  PMID: 21671252
Integral Approximation; Linearization; GLIMMIX; lme4; NLMIXED; R; SAS; ZELIG
13.  A Randomized Effectiveness Trial of Interpersonal Psychotherapy for Depressed Women With Sexual Abuse Histories 
Many depressed women seen in community mental health centers (CMHCs) have histories of childhood sexual abuse and are economically disadvantaged. Randomized trials are needed to test the effectiveness of evidence-based interventions in this population and setting. This study compared interpersonal psychotherapy with usual care psychotherapy among women in a CMHC.
Among 1,100 women seeking treatment in a CMHC, 230 (21%) had major depression and histories of childhood sexual abuse. Seventy women with major depression and sexual abuse before age 18 were randomly assigned to interpersonal psychotherapy (N=37) or usual care psychotherapy (N=33). Staff clinicians provided all treatments. Participants were assessed at study entry and at ten, 24, and 36 weeks after random assignment. Generalized estimating equations were used to examine change over time.
Compared with women assigned to usual care, women who received interpersonal psychotherapy had greater reductions in depressive symptoms (Hamilton Rating Scale, p=.05, d=.34; Beck Depression Inventory–II, p=.01, d=.29), posttraumatic stress disorder symptoms (p=.04, d=.76), and shame (p=.002, d=.38). Interpersonal psychotherapy and usual care yielded comparable improvements in social and mental health–related functioning.
Interpersonal psychotherapy compared favorably to usual care psychotherapy in a CMHC in improving psychiatric symptoms and reducing shame among sexually abused women. However, there is a critical need for continued research to develop more effective treatments for the social and psychiatric sequelae of interpersonal trauma and socioeconomic disadvantage.
PMCID: PMC3140209  PMID: 21459988
14.  Outcomes of Subsyndromal Depression in Older Primary Care Patients 
Most older persons in primary care suffering clinically significant depressive symptoms do not meet criteria for major or minor depression. We tested the hypothesis that patients with subsyndromal depression (SSD) would have poorer psychiatric, medical, and functional outcomes at follow-up than non-depressed patients, but not as poor as those with minor or major depression. We also explored the relative outcomes of three definitions of SSD to determine their relative prognostic value.
Prospective observational cohort study.
Primary care practices in Monroe County, NY.
481 primary care patients age ≥65 years who completed research assessments at intake and at least one year of follow-up evaluation.
Depression diagnoses and three definitions of SSD were determined by the Structured Clinical Interview for DSM-IV and the 24-item Hamilton Depression Rating Scale. Other validated measures assessed anxiety, cognition, medical burden, and functional status.
Patients with SSD had poorer 1-year lagged outcomes than non-depressed subjects in terms of psychiatric symptoms and functional status, often not significantly different than major or minor depression. Two of the SSD definitions identified subjects with poorer psychiatric and functional outcomes than the third SSD definition.
Clinicians should be vigilant in caring for patients with SSD, monitoring for persistent or worsening depressive symptoms including suicidality, anxiety, cognitive impairment, and functional decline. Researchers may use particular SSD definitions to identify individuals at higher risk of poor outcomes, to better understand the relationships of SSD to functional disability and to test innovative preventive and therapeutic interventions.
PMCID: PMC2827819  PMID: 20173424
depression; geriatrics; primary care
16.  The Effect of Interpersonal Psychotherapy for Depression on Insomnia Symptoms in a Cohort of Women with Sexual Abuse Histories 
Journal of traumatic stress  2009;22(6):634-638.
Insomnia frequently occurs with trauma exposure and depression, but can ameliorate with improvements in depression. Insomnia was assessed by the insomnia subscale of the Hamilton Rating Scale for Depression in 106 women with childhood sexual abuse (CSA) and major depression receiving Interpersonal Psychotherapy in an uncontrolled pilot (n = 36) and an immediately subsequent randomized controlled trial (n = 70) comparing IPT to treatment as usual. Depression improved in each study and in both treatment conditions; insomnia had smaller, non-significant improvements. Overall, 95 women (90%) endorsed insomnia on the Structured Clinical Interview for DSM-IV at baseline and, of those, 90% endorsed insomnia following treatment. Despite improvements in depression, insomnia persists for most women with CSA.
PMCID: PMC2798908  PMID: 19885874
17.  Connecting the Invisible Dots: Network-Based Methods to Reach a Hidden Population at Risk for Suicide 
Social science & medicine (1982)  2009;69(3):469-474.
Young lesbian, gay, and bisexual (young LGB) individuals report higher rates of suicide ideation and attempts from their late teens through early twenties. Their high rate of Internet use suggests that online social networks offer a novel opportunity to reach them. This study explores online social networks as a venue for prevention research targeting young LGB. An automated data collection program was used to map the social connections between LGB self-identified individuals between 16 and 24 years old participating in an online social network. We then completed a descriptive analysis of the structural characteristics known to affect diffusion within such networks. Finally, we conducted Monte Carlo simulations of peer-driven diffusion of a hypothetical preventive intervention within the observed network under varying starting conditions. We mapped a network of 100,014 young LGB. The mean age was 20.4 years. The mean nodal degree was 137.5, representing an exponential degree distribution ranging from 1 through 4,309. Monte Carlo simulations revealed that a peer-driven preventive intervention ultimately reached final sample sizes of up to 18,409 individuals. The network’s structure is consistent with other social networks in terms of the underlying degree distribution. Such networks are typically formed dynamically through a process of preferential attachment. This implies that some individuals could be more important to target to facilitate the diffusion of interventions. However, in terms of determining the success of an intervention targeting this population, our simulation results suggest that varying the number of peers that can be recruited is more important than increasing the number of randomly-selected starting individuals. This has implications for intervention design. Given the potential to access this previously isolated population, this novel approach represents a promising new frontier in suicide prevention and other research areas.
PMCID: PMC2768574  PMID: 19540641
adolescent suicide; adult suicide; human sexuality; network analysis; Internet; algorithms; lesbian; gay; bisexual
18.  On the Impact of Parametric Assumptions and Robust Alternatives for Longitudinal Data Analysis 
Models for longitudinal data are employed in a wide range of behavioral, biomedical, psychosocial, and health-care related research. One popular model for continuous response is the linear mixed-effects model (LMM). Although simulations by recent studies show that LMM provides reliable estimates under departures from the normality assumption for complete data, the invariable occurrence of missing data in practical studies renders such robustness results less useful when applied to real study data. In this paper, we show by simulated studies that in the presence of missing data estimates of the fixed-effect of LMM are biased under departures from normality. We discuss two robust alternatives, the weighted generalized estimating equations (WGEE) and the augmented WGEE (AWGEE), and compare their performances with LMM using real as well as simulated data. Our simulation results show that both WGEE and AWGEE provide valid inference for skewed non-normal data when missing data follows the missing at random (MAR), the most popular missing data mechanism for real study data.
PMCID: PMC2875790  PMID: 19688758
Augmented weighted generalized estimating equations; double robust estimate; missing at random; surrogacy assumption; weighted generalized estimating equations

Results 1-18 (18)