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author:("Li, nybelin")
1.  Evaluation of a Pilot Communication Skills Training Intervention for Minority Cancer Patients 
Journal of psychosocial oncology  2011;29(4):347-358.
The aim of this study was to pilot test in a minority cancer patient population a communication workshop to improve doctor-patient communication skills. Thirty-two patients participated. Eighteen evaluated a face-to-face workshop, while 14 completed surveys only. Participants in the workshop group completed the Patient Report of Communication Behavior (PRCB) before and after the workshop and a course evaluation. Participants did not differ on baseline PRCB scores. Post-test scores were significantly higher than pre-test scores (p<.01). All participants agreed or strongly agreed that they would use the communication skills; 93% agreed or strongly agreed that the skills would improve their healthcare.
PMCID: PMC4322131  PMID: 21966720
oncology; communication skills training; patient education; minority patients
2.  Femtosecond Laser Pulse Driven Melting in Gold Nanorod Aqueous Colloidal Suspension: Identification of a Transition from Stretched to Exponential Kinetics 
Scientific Reports  2015;5:8146.
Many potential industrial, medical, and environmental applications of metal nanorods rely on the physics and resultant kinetics and dynamics of the interaction of these particles with light. We report a surprising kinetics transition in the global melting of femtosecond laser-driven gold nanorod aqueous colloidal suspension. At low laser intensity, the melting exhibits a stretched exponential kinetics, which abruptly transforms into a compressed exponential kinetics when the laser intensity is raised. It is found the relative formation and reduction rate of intermediate shapes play a key role in the transition. Supported by both molecular dynamics simulations and a kinetic model, the behavior is traced back to the persistent heterogeneous nature of the shape dependence of the energy uptake, dissipation and melting of individual nanoparticles. These results could have significant implications for various applications such as water purification and electrolytes for energy storage that involve heat transport between metal nanorod ensembles and surrounding solvents.
PMCID: PMC4311257  PMID: 25634673
3.  Examining intuitive risk perceptions for cancer in diverse populations 
Health, risk & society  2014;16(3):227-242.
In this article we examine intuitive dimensions of personal cancer risk likelihood, which theory and empirical evidence indicate may be important elements in the risk perception process. We draw on data from a study of risk perceptions in three social groups, university students, men living in the community, and primary care patients living in urban area. The study took place in 2007-2011, in New York State (Garden City and New York City) and Boston, Massachusetts. This study used items developed from categories identified in prior qualitative research specifying emotions and attitudes activated in cancer risk determination to examine perception of cancer risks. Across three samples - university students (N=568), community men (N=182), and diverse, urban primary care patients (N=127) - we conducted exploratory factor and construct analyses. We found that the most reliable two factors within the five-factor solution were Cognitive Causation, tapping beliefs that risk thoughts may encourage cancer development, and Negative Affect in Risk, assessing negative feelings generated during the risk perception process. For these factors, there were high levels of item endorsement, especially in minority groups, and only modest associations with established cancer risk perception and worry assessments, indicating novel content. These items may prove useful in measuring and comparing intuitive cancer risk perceptions across diverse population subgroups.
PMCID: PMC4078890  PMID: 24999304
intuition; risk; risk perceptions; diverse populations; measure development; cancer risk perceptions; decision-making
4.  Dentists United to Extinguish Tobacco (DUET): a study protocol for a cluster randomized, controlled trial for enhancing implementation of clinical practice guidelines for treating tobacco dependence in dental care settings 
Although dental care settings provide an exceptional opportunity to reach smokers and provide brief cessation advice and treatment to reduce oral and other tobacco-related health conditions, dental care providers demonstrate limited adherence to evidence-based guidelines for treatment of tobacco use and dependence.
Guided by a multi-level, conceptual framework that emphasizes changes in provider beliefs and organizational characteristics as drivers of improvement in tobacco treatment delivery, the current protocol will use a cluster, randomized design and multiple data sources (patient exit interviews, provider surveys, site observations, chart audits, and semi-structured provider interviews) to study the process of implementing clinical practice guidelines for treating tobacco dependence in 18 public dental care clinics in New York City. The specific aims of this comparative-effectiveness research trial are to: compare the effectiveness of three promising strategies for implementation of tobacco use treatment guidelines—staff training and current best practices (CBP), CBP + provider performance feedback (PF), and CBP + PF + provider reimbursement for delivery of tobacco cessation treatment (pay-for-performance, or P4P); examine potential theory-driven mechanisms hypothesized to explain the comparative effectiveness of three strategies for implementation; and identify baseline organizational factors that influence the implementation of evidence-based tobacco use treatment practices in dental clinics. The primary outcome is change in providers’ tobacco treatment practices and the secondary outcomes are cost per quit, use of tobacco cessation treatments, quit attempts, and smoking abstinence.
We hypothesize that the value of these promising implementation strategies is additive and that incorporating all three strategies (CBP, PF, and P4P) will be superior to CBP alone and CBP + PF in improving delivery of cessation assistance to smokers. The findings will improve knowledge pertinent to the implementation, dissemination, and sustained utilization of evidence-based tobacco use treatment in dental practices.
Trial registration
PMCID: PMC3936874  PMID: 24559178
Dental care; Clinical practice guidelines; Treatment of tobacco dependence; Tobacco cessation
5.  Using R and WinBUGS to fit a Generalized Partial Credit Model for developing and evaluating patient-reported outcomes assessments 
Statistics in medicine  2012;31(18):2010-2026.
The US Food and Drug Administration recently announced the final guidelines on the development and validation of Patient-Reported Outcomes (PROs) assessments in drug labeling and clinical trials. This guidance paper may boost the demand for new PRO survey questionnaires. Henceforth biostatisticians may encounter psychometric methods more frequently, particularly Item Response Theory (IRT) models to guide the shortening of a PRO assessment instrument. This article aims to provide an introduction on the theory and practical analytic skills in fitting a Generalized Partial Credit Model in IRT (GPCM). GPCM theory is explained first, with special attention to a clearer exposition of the formal mathematics than what is typically available in the psychometric literature. Then a worked example is presented, using self-reported responses taken from the International Personality Item Pool. The worked example contains step-by-step guides on using the statistical languages R and WinBUGS in fitting the GPCM. Finally, the Fisher information function of the GPCM model is derived and used to evaluate, as an illustrative example, the usefulness of assessment items by their information contents. This article aims to encourage biostatisticians to apply IRT models in the re-analysis of existing data and in future research.
PMCID: PMC3926129  PMID: 22362655
Item Response Theory; Generalized Partial Credit Model; Rasch Model
6.  Initial Reactions to Tobacco Use and Risk of Future Regular Use 
Nicotine & Tobacco Research  2012;15(2):509-517.
Introduction: Studies suggest that initial smoking pleasure influences future smoking behavior. We investigated how initial reactions to cigarettes or Swedish smokeless tobacco (snus) were associated with future use among 10,708 adults from the Swedish Twin Registry.
Methods: The Early Smoking Experience questionnaire captured physiologic reactions to initial tobacco use. Binary recursive partitioning (BRP) identified combinations of initial reactions predictive of regular tobacco use. Analyses, stratified by sex, were conducted separately among those who experimented with only cigarettes (EC), only snus (ES), and both products (EC+S).
Results: Among EC, 39.8% of men and 43.7% of women became smokers, while among ES, 78.6% of men and 53.7% of women became snus users. Among EC+S, 31.3% of men and 20.0% of women became dual users. BRP identified different reactions as predictive of future smoking for men (buzz) and women (dizziness, difficulty inhaling). No initial reaction predicted future snus use among men, but pleasant sensations, later age at first use, and relaxation predicted future snus use for women. Among EC+S, future exclusive use of either product was associated with a favorable initial reaction to that product. Dual users experienced higher prevalence of pleasant reactions and lower prevalence of unpleasant reactions in response to both products.
Conclusions: Our findings support that those who progress to regular tobacco use may be sensitive to the rewarding effects of nicotine but suggest that initial reactions differ by tobacco type. A high proportion of men became regular snus users regardless of initial reactions.
PMCID: PMC3612000  PMID: 22949572
7.  Changes in Forest Soil Properties in Different Successional Stages in Lower Tropical China 
PLoS ONE  2013;8(11):e81359.
Natural forest succession often affects soil physical and chemical properties. Selected physical and chemical soil properties were studied in an old-growth forest across a forest successional series in Dinghushan Nature Reserve, Southern China.
Methodology/Principal Findings
The aim was to assess the effects of forest succession change on soil properties. Soil samples (0–20 cm depth) were collected from three forest types at different succession stages, namely pine (Pinus massoniana) forest (PMF), mixed pine and broadleaf forest (PBMF) and monsoon evergreen broadleaf forest (MEBF), representing early, middle and advanced successional stages respectively. The soil samples were analyzed for soil water storage (SWS), soil organic matter (SOM), soil microbial biomass carbon (SMBC), pH, NH4+-N, available potassium (K), available phosphorus (P) and microelements (available copper (Cu), available zinc (Zn), available iron (Fe) and available boron (B)) between 1999 and 2009. The results showed that SWS, SOM, SMBC, Cu, Zn, Fe and B concentrations were higher in the advanced successional stage (MEBF stage). Conversely, P and pH were lower in the MEBF but higher in the PMF (early successional stage). pH, NH4+-N, P and K declined while SOM, Zn, Cu, Fe and B increased with increasing forest age. Soil pH was lower than 4.5 in the three forest types, indicating that the surface soil was acidic, a stable trend in Dinghushan.
These findings demonstrated significant impacts of natural succession in an old-growth forest on the surface soil nutrient properties and organic matter. Changes in soil properties along the forest succession gradient may be a useful index for evaluating the successional stages of the subtropical forests. We caution that our inferences are drawn from a pseudo-replicated chronosequence, as true replicates were difficult to find. Further studies are needed to draw rigorous conclusions regarding on nutrient dynamics in different successional stages of forest.
PMCID: PMC3828269  PMID: 24244738
8.  Measurement of Affective and Activity Pain Interference Using the Brief Pain Inventory (BPI): Cancer and Leukemia Group B 70903* 
Pain medicine (Malden, Mass.)  2012;13(11):1417-1424.
The Brief Pain Inventory (BPI) was designed to yield separate scores for pain intensity and interference. It has been proposed that the pain interference factor can be further broken down into unique factors of affective (e.g., mood) and activity (e.g., work) interference. The purpose of this analysis was to confirm this affective/activity interference dichotomy.
Patients and Methods
A retrospective confirmatory factor analysis was completed for a sample of 184 individuals diagnosed with castrate-resistant prostate cancer (Age 40–86, M = 65.46, 77% White Non-Hispanic) who had been administered the BPI as part of Cancer and Leukemia Group B (CALGB) trial 9480. A one-factor model was compared against two-factor and three-factor models that were developed based on the design of the instrument.
Root mean squared error of approximation (0.075), comparative fit index (0.971), and change in chi-square, given the corresponding change in degrees of freedom (13.33, p < .05) values for the three-factor model (i.e., pain intensity, activity interference, and affective interference) were statistically superior in comparison to the one- and two-factor models. This three-factor structure was found to be invariant across age, mean PSA and hemoglobin levels.
These results confirm that the BPI can be used to quantify the degree to which pain separately interferes with affective and activity aspects of a patient's everyday life. These findings will provide clinical trialists, pharmaceutical sponsors, and regulators with confidence in the flexibility of the BPI as they consider the use of this instrument to assist with understanding the patient experience as it relates to treatment.
PMCID: PMC3796944  PMID: 23110676
Measurement; Cancer Pain; Quality of Life
9.  Toward a greater understanding of breast cancer patients’ decisions to discuss cancer related internet information with their doctors: An exploratory study 
Patient education and counseling  2012;89(1):109-115.
To investigate differences between breast cancer patients who do and do not discuss cancer-related internet information (CRII) with their doctors.
70 breast cancer patients completed questionnaires regarding internet use, discussions about CRII, and the doctor-patient relationship.
No significant differences were noted across patient, disease, or visit characteristics, or physician reliance between those who intended to discuss CRII and those who did not. Patients who intended to discuss CRII rated significantly higher pre-consultation anxiety levels. No significant differences in satisfaction, anxiety reduction, or trust in physician were found between patients who had discussed and those who had not. Patients’ reasons for discussing or not discussing are detailed.
Factors influencing patients’ decisions to discuss CRII are complex and differ from those identified as leading patients to seek internet information. Future research about internet discussions should investigate the impact of patients’ preferred role in treatment, the doctor-patient relationship, anxiety level, attributes of CRII, and physician trust.
Practice Implications
Understanding the characteristics of patients who do and do not discuss internet information is important given the impact internet information has on healthcare communication and the doctor-patient relationship, including the development of interventions aimed at improving such interactions.
PMCID: PMC3462296  PMID: 22722063
internet; doctor-patient communication; breast cancer
10.  Testing the utility of a cancer clinical trial specific Question Prompt List (QPL-CT) during oncology consultations 
Patient education and counseling  2012;88(2):311-317.
A Question Prompt List (QPL) is a proven, simple intervention to aid patients to be active participants in consultations with their physicians by asking questions. We aimed to further develop and test the efficacy of a targeted QPL for clinical trials (QPL-CT).
Breast, Lung and Genitourinary cancer patients who were facing a discussion about a therapeutic clinical trial completed short pre- and post-consultation questionnaires and used the QPL-CT in their discussions with their oncologists.
Results: 30 participants were recruited from 6 oncologists
All QPL-CT questions were selected by at least one-third of participants. Participants mostly wanted and asked questions about personal trial benefit. Oncologists provided information about personal benefit to varying degrees, thus patients did not ask some questions. Patients were still left with some unasked and unanswered questions.
The QPL-CT has potential as a simple, inexpensive intervention to aid such communication. Further investigation is needed to demonstrate the efficacy of the QPL-CT in improving cancer patient outcomes.
Practice Implications
These preliminary finding suggest that important areas of clinical trials are overlooked in clinical consultations. The QPL-CT may be an effective method to encourage oncologists to endorse patient question asking about clinical trials and prompt patient questions.
PMCID: PMC3376695  PMID: 22390854
Clinical Trials; Question Prompt Lists; Physician-patient communication
11.  Perceived risk for cancer in an urban sexual minority 
Journal of behavioral medicine  2010;34(3):157-169.
Lesbians, gay men, and bisexuals are a sexual minority experiencing elevated cancer risk factors and health disaparites, e.g., elevated tobacco use, disproportionate rates of infection with human immunodeficiency virus. Little attention has been paid to cancer prevention, education, and control in sexual minorities. This study describes cancer risk perceptions and their correlates so as to generate testable hypotheses and provide a foundation for targeting cancer prevention and risk reduction efforts in this high risk population. A cross-sectional survey of affiliates of a large urban community center serving sexual minority persons yielded a study sample of 247 anonymous persons. The survey assessed demographics, absolute perceived cancer risk, cancer risk behaviors, desired lifestyle changes to reduce cancer risk, and psychosocial variables including stress, depression, and stigma. Univariate and multivariate nonparametric statistics were used for analyses. The sample was primarily white non-Hispanic, middle-aged, and > 80% had at least a high school education. Mean values for absolute perceived cancer risk (range 0–100% risk), were 43.0 (SD = 25.4) for females, and for males, 49.3 (SD = 24.3). For females, although the multivariate regression model for absolute perceived cancer risk was statistically significant (P < .05), no single model variable was significant. For men, the multivariate regression model was significant (P < .001), with endorsement of “don't smoke/quit smoking” to reduce personal cancer risk (P < .001), and greater number of sexual partners (P = .054), positively associated with absolute perceived risk for cancer. This study provides novel data on cancer risk perceptions in sexual minorities, identifying correlates of absolute perceived cancer risk for each gender and several potential foci for cancer prevention interventions with this at-risk group.
PMCID: PMC3684154  PMID: 20872174
Cancer risk perception; Cancer risk factors; Sexual minority; Health disparities
12.  Reliability of adverse symptom event reporting by clinicians 
Adverse symptom event reporting is vital as part of clinical trials and drug labeling to ensure patient safety and inform risk–benefit decision making. The purpose of this study was to assess the reliability of adverse event reporting of different clinicians for the same patient for the same visit.
A retrospective reliability analysis was completed for a sample of 393 cancer patients (42.8% men; age 26–91, M = 62.39) from lung (n = 134), prostate (n = 113), and Ob/Gyn (n = 146) clinics. These patients were each seen by two clinicians who independently rated seven Common Terminology Criteria for Adverse Events (CTCAE) symptoms. Twenty-three percent of patients were enrolled in therapeutic clinical trials.
The average time between rater evaluations was 68 min. Intraclass correlation coefficients were moderate for constipation (0.50), diarrhea (0.58), dyspnea (0.69), fatigue (0.50), nausea (0.52), neuropathy (0.71), and vomiting (0.46). These values demonstrated stability over follow-up visits. Two-point differences, which would likely affect treatment decisions, were most frequently seen among symptomatic patients for constipation (18%), vomiting (15%), and nausea (8%).
Agreement between different clinicians when reporting adverse symptom events is moderate at best. Modification of approaches to adverse symptom reporting, such as patient self-reporting, should be considered.
PMCID: PMC3633532  PMID: 21984468
Drug toxicity; Reproducibility of results; Risk assessment; Statistical data interpretation
13.  Pilot Randomized Controlled Trial of Individual Meaning-Centered Psychotherapy for Patients With Advanced Cancer 
Journal of Clinical Oncology  2012;30(12):1304-1309.
Spiritual well-being and sense of meaning are important concerns for clinicians who care for patients with cancer. We developed Individual Meaning-Centered Psychotherapy (IMCP) to address the need for brief interventions targeting spiritual well-being and meaning for patients with advanced cancer.
Patients and Methods
Patients with stage III or IV cancer (N = 120) were randomly assigned to seven sessions of either IMCP or therapeutic massage (TM). Patients were assessed before and after completing the intervention and 2 months postintervention. Primary outcome measures assessed spiritual well-being and quality of life; secondary outcomes included anxiety, depression, hopelessness, symptom burden, and symptom-related distress.
Of the 120 participants randomly assigned, 78 (65%) completed the post-treatment assessment and 67 (56%) completed the 2-month follow-up. At the post-treatment assessment, IMCP participants demonstrated significantly greater improvement than the control condition for the primary outcomes of spiritual well-being (b = 0.39; P <.001, including both components of spiritual well-being (sense of meaning: b = 0.34; P = .003 and faith: b = 0.42; P = .03), and quality of life (b = 0.76; P = .013). Significantly greater improvements for IMCP patients were also observed for the secondary outcomes of symptom burden (b = −6.56; P < .001) and symptom-related distress (b = −0.47; P < .001) but not for anxiety, depression, or hopelessness. At the 2-month follow-up assessment, the improvements observed for the IMCP group were no longer significantly greater than those observed for the TM group.
IMCP has clear short-term benefits for spiritual suffering and quality of life in patients with advanced cancer. Clinicians working with patients who have advanced cancer should consider IMCP as an approach to enhance quality of life and spiritual well-being.
PMCID: PMC3646315  PMID: 22370330
14.  Validity of the Process of Change for Colorectal Cancer Screening Among African Americans 
Process of change (POC) is a construct of the transtheoretical model that proposes to promote healthy behaviors.
African Americans participate in colorectal cancer (CRC) screening less often than whites, while disease onset is younger, and incidence and mortality from CRC are higher.
POC items for CRC screening were administered to 158 African Americans, the majority of whom were female (75.9%) and were not employed (85.4%). Confirmatory factor analysis was used to validate four factors reflecting the POC sub-domains.
Support of the factor validity of the POC with internal consistency of standardized alpha for the four factors was found. A logistic regression showed predictive validity in predicting current screening stage for two of the four sub-domains.
These data support the application of the POC to prediction of CRC screening intention among African Americans.
PMCID: PMC3626411  PMID: 21165726
Transtheoretical model; Process of change; Colorectal cancer; Screening; Validity
15.  A Time-Varying Effect Model for Intensive Longitudinal Data 
Psychological Methods  2011;17(1):61-77.
Understanding temporal change in human behavior and psychological processes is a central issue in the behavioral sciences. With technological advances, intensive longitudinal data (ILD) are increasingly generated by studies of human behavior that repeatedly administer assessments over time. ILD offer unique opportunities to describe temporal behavioral changes in detail and identify related environmental and psychosocial antecedents and consequences. Traditional analytical approaches impose strong parametric assumptions about the nature of change in the relationship between time-varying covariates and outcomes of interest. This paper introduces time-varying effect models (TVEM) that explicitly model changes in the association between ILD covariates and ILD outcomes over time in a flexible manner. In this article, we describes unique research questions that the TVEM addresses, outline the model-estimation procedure, share a SAS macro for implementing the model, demonstrate model utility with a simulated example, and illustrate model applications in ILD collected as part of a smoking-cessation study to explore the relationship between smoking urges and self-efficacy during the course of the pre- and post- cessation period.
PMCID: PMC3288551  PMID: 22103434
intensive longitudinal data; time-varying effect model; non-parametric; P-spline; applications
16.  Randomized Trial of Expressive Writing for Distressed Metastatic Breast Cancer Patients 
Psychology & health  2011;27(1):88-100.
Women with metastatic breast cancer and significant psychological distress (N = 87) were assigned randomly to engage in four home-based sessions of expressive writing or neutral writing. Women in the expressive writing group wrote about their deepest thoughts and feelings regarding their cancer, whereas women in the neutral writing group wrote about their daily activities in a factual manner. No statistically significant group differences in existential and psychological well-being, fatigue, and sleep quality were found at 8-weeks post-writing. However, the expressive writing group reported significantly greater use of mental health services during the study than the neutral writing group (55% vs. 26%, respectively; p < .05). Findings suggest that expressive writing may improve uptake of mental health services among distressed cancer patients, but is not broadly effective as a psychotherapeutic intervention.
PMCID: PMC3175346  PMID: 21678181
metastatic breast cancer; expressive writing; psychological distress; sleep; fatigue
17.  Poisson Growth Mixture Modeling of Intensive Longitudinal Data: An Application to Smoking Cessation Behavior 
Intensive longitudinal data (ILD) have become increasingly common in the social and behavioral sciences; count variables, such as the number of daily smoked cigarettes, are frequently-used outcomes in many ILD studies. We demonstrate a generalized extension of growth mixture modeling (GMM) to Poisson-distributed ILD for identifying qualitatively distinct trajectories in the context of developmental heterogeneity in count data. Accounting for the Poisson outcome distribution is essential for correct model identification and estimation. In addition, setting up the model in a way that is conducive to ILD measures helps with data complexities – large data volume, missing observations, and differences in sampling frequency across individuals. We present technical details of model fitting, summarize an empirical example of patterns of smoking behavior change, and describe research questions the generalized GMM helps to address.
PMCID: PMC3294500  PMID: 22408365
intensive longitudinal data; count data; generalized growth mixture modeling; model enumeration; smoking cessation
18.  Interpretation of Melanoma Risk Feedback in First-Degree Relatives of Melanoma Patients 
Journal of Cancer Epidemiology  2012;2012:374842.
Little is known about how individuals might interpret brief genetic risk feedback. We examined interpretation and behavioral intentions (sun protection, skin screening) in melanoma first-degree relatives (FDRs) after exposure to brief prototypic melanoma risk feedback. Using a 3 by 2 experimental pre-post design where feedback type (high-risk mutation, gene environment, and nongenetic) and risk level (positive versus negative findings) were systematically varied, 139 melanoma FDRs were randomized to receive one of the six scenarios. All scenarios included an explicit reminder that melanoma family history increased their risk regardless of their feedback. The findings indicate main effects by risk level but not feedback type; positive findings led to heightened anticipated melanoma risk perceptions and anticipated behavioral intentions. Yet those who received negative findings often discounted their family melanoma history. As such, 25%, 30%, and 32% of those who received negative mutation, gene-environment, and nongenetic feedback, respectively, reported that their risk was similar to the general population. Given the frequency with which those who pursue genetic testing may receive negative feedback, attention is needed to identify ideal strategies to present negative genetic findings in contexts such as direct to consumer channels where extensive genetic counseling is not required.
PMCID: PMC3410311  PMID: 22888347
19.  Exposure to and Intention to Discuss Cancer-Related Internet Information Among Patients With Breast Cancer 
Journal of Oncology Practice  2011;8(1):40-45.
An assessment of the frequency with which patients with breast cancer attend physician visits having recently read and intending to discuss cancer-related information from the Internet.
Previous studies have reported a significant number of patients with breast cancer seek cancer-related information from the Internet. Most studies have asked whether a patient has ever read Internet information since her diagnosis. The purpose of this study was to assess the frequency with which patients with breast cancer come to physician appointments having recently read and intending to discuss cancer-related information from the Internet.
Patients and Methods:
We asked 558 patients with breast cancer who were waiting to see their physicians about their experiences reading cancer-related information from the Internet and their intent to discuss the information in their current visit.
Fifteen percent reported reading cancer-related Internet information in the past month. Patients who had read such information in the past month were younger, had been diagnosed more recently, and were more likely to be attending a new visit. Of those who had read in the past month, 45% reported intending to discuss what they had read with their physician. Nineteen percent of patients reported having ever read breast cancer–related Internet information since their diagnosis.
The proportion of patients with breast cancer planning to discuss Internet information during their current physician visit was relatively small. Few characteristics were associated with recent Internet use or intent to discuss.
PMCID: PMC3266315  PMID: 22548010
20.  Using Confirmatory Factor Analysis to Evaluate Construct Validity of the Brief Pain Inventory (BPI) 
The Brief Pain Inventory (BPI) is a frequently used instrument designed to assess the patient-reported outcome of pain. The majority of factor analytic studies have found a two-factor (i.e., pain intensity and pain interference) structure for this instrument; however, since the BPI was developed with an a priori hypothesis of the relationship among its items, it follows that construct validity investigations should utilize confirmatory factor analysis (CFA).
The purpose of this work is to establish the construct validity of the BPI using a CFA framework and demonstrate factorial invariance using a range of demographic variables.
A retrospective CFA was completed in a sample of individuals diagnosed with HIV/AIDS and cancer (n = 364; 63% male; age 21-92 years, M = 51.80). A baseline one-factor model was compared against two-factor and three-factor models (i.e., pain intensity, activity interference, and affective interference) that were developed based on the hypothetical design of the instrument.
Fit indices for the three-factor model were statistically superior when compared to the one-factor model and marginally better in comparison to the two-factor model. This three-factor structure was found to be invariant across disease, age, and ethnicity groups.
The results of this study provide evidence to support a three-factor representation of the BPI, as well as the originally hypothesized two-factor structure. Such findings will begin to provide clinical trialists, pharmaceutical sponsors, and regulators with confidence in the psychometric properties of this instrument when considering its inclusion in clinical research.
PMCID: PMC3062715  PMID: 21131166
Factor analysis; psychometrics; pain; reproducibility of results; affective symptoms
21.  Longitudinal Assessment of Cognitive Changes Associated With Adjuvant Treatment for Breast Cancer: Impact of Age and Cognitive Reserve 
Journal of Clinical Oncology  2010;28(29):4434-4440.
To examine the impact of age and cognitive reserve on cognitive functioning in patients with breast cancer who are receiving adjuvant treatments.
Patients and Methods
Patients with breast cancer exposed to chemotherapy (n = 60; mean age, 51.7 years) were evaluated with a battery of neuropsychological and psychological tests before treatment and at 1, 6, and 18 months after treatment. Patients not exposed to chemotherapy (n = 72; mean age, 56.6 years) and healthy controls (n = 45; mean age, 52.9 years) were assessed at matched intervals.
Mixed-effects modeling revealed significant effects for the Processing Speed and Verbal Ability domains. For Processing Speed, a three-way interaction among treatment group, age, and baseline cognitive reserve (P < .001) revealed that older patients with lower baseline cognitive reserve who were exposed to chemotherapy had lower performance on Processing Speed compared with patients not exposed to chemotherapy (P = .003) and controls (P < .001). A significant group by time interaction for Verbal Ability (P = .01) suggested that the healthy controls and no chemotherapy groups improved over time. The chemotherapy group failed to improve at 1 month after treatment but improved during the last two follow-up assessments. Exploratory analyses suggested a negative effect of tamoxifen on Processing Speed (P = .036) and Verbal Memory (P = .05) in the no-chemotherapy group.
These data demonstrated that age and pretreatment cognitive reserve were related to post-treatment decline in Processing Speed in women exposed to chemotherapy and that chemotherapy had a short-term impact on Verbal Ability. Exploratory analysis of the impact of tamoxifen suggests that this pattern of results may be due to a combination of chemotherapy and tamoxifen.
PMCID: PMC2988635  PMID: 20837957
22.  Visual P2-N2 complex and arousal at the time of encoding predict the time domain characteristics of amnesia for multiple intravenous anesthetic drugs in humans 
Anesthesiology  2010;113(2):313-326.
Intravenous anesthetics have marked effects on memory function, even at subclinical concentrations. Fundamental questions remain in characterizing anesthetic amnesia and identifying affected systems-level processes. We applied a mathematical model to evaluate time-domain components of anesthetic amnesia in human subjects.
61 volunteers were randomized to receive propofol (n = 12), thiopental (13), midazolam (12), dexmedetomidine (12), or placebo (12). With drug present, subjects encoded pictures into memory using a 375-item continuous recognition task, with subsequent recognition later probed with drug absent. Memory function was sampled at up to 163 time points, and modeled over the time domain using a two-parameter, first-order negative power function. The parietal event-related P2-N2 complex was derived from electroencephalography, and arousal repeatedly sampled. Each drug was evaluated at two concentrations.
The negative power function consistently described the course of amnesia (mean R2 = 0.854), but there were marked differences between drugs in the modulation of individual components (P < 0.0001). Initial memory strength was a function of arousal (P = 0.005), while subsequent decay was related to reaction time (P < 0.0001) and the P2-N2 complex (P = 0.007/0.002 for discrete components).
In humans, the amnesia caused by multiple intravenous anesthetic drugs is characterized by arousal-related effects on initial trace strength, and a subsequent decay predicted by attenuation of the P2-N2 complex at encoding. We propose that failure of normal memory consolidation follows drug-induced disruption of interregional synchrony critical for neuronal plasticity, and discuss our findings in the framework of memory systems theory.
PMCID: PMC2910207  PMID: 20613477
23.  Classification and Regression Tree Uncovered Hierarchy of Psychosocial Determinants Underlying Quality Of Life Response Shift in HIV/AIDS 
Journal of clinical epidemiology  2009;62(11):1138-1147.
Rapkin and Schwartz [1] define response shift as otherwise unexplained, discrepant change in HRQOL that is associated with change in cognitive appraisal. In this paper, we demonstrate how a Recursive Partitioning (RPART) regression tree analytic approach may be used to explore cognitive changes to gain additional insight into response shift phenomena.
Study Design and Setting
Data are from the “Choices in Care Study,” [2], an evaluation of HIV+ Medicaid recipients’ experiences and outcomes in care (N = 394). Cognitive assessment was based on the Quality of Life Appraisal Battery. HRQOL was measured by the MOS-SF36v2 [3].
We used RPART to examine six-month change in MOS mental composite as a function of changes in appraisal, after controlling for patient characteristics, health changes and intervening events. RPART identified nine distinct patterns of cognitive change, including three associated with negative discrepancies, four with positive discrepancies, and two with no discrepancies.
RPART classification provides a nuanced treatment of response shift. This methodology has implications for evaluating programs, guiding decisions and targeting care.
PMCID: PMC2754600  PMID: 19595576
response shift; health related quality of life; classification and regression trees
24.  Barriers to Mental Health Service Use among Hematopoietic Stem Cell Transplant Survivors 
Bone marrow transplantation  2009;45(3):570-579.
This study examined barriers to mental health service use and their demographic, medical, and psychosocial correlates among hematopoietic stem cell transplant (HSCT) survivors. A sample of 253 HSCT survivors who were 1- to 3-years post-transplant completed measures of demographic, physical, psychological, and social characteristics as well as a newly modified measure of barriers to mental health service use. Only 50% of distressed HSCT survivors had received mental health services. An exploratory factor analysis of the barriers to mental health service use scale yielded four factors: Scheduling Barriers, Knowledge Barriers, Emotional Barriers, and Illness-related Barriers. Patients with higher social constraints (perceived problems discussing the illness experience with significant others) reported higher levels of all four types of barriers. General distress and transplant-related posttraumatic stress symptoms were positively associated with emotional, knowledge, and illness-related barriers to mental health service use, whereas physical and functional well-being were inversely associated with these barriers. Having more knowledge barriers and more emotional barriers predicted a lower likelihood of receiving mental health services, as did lower levels of education and general distress. Results suggest that a significant number of HSCT survivors may benefit from education about mental health services that is tailored to individual barriers.
PMCID: PMC2866642  PMID: 19597417
hematopoietic stem cell transplantation; cancer survivorship; barriers; mental health services; psychological
25.  Propofol and midazolam inhibit conscious memory processes very soon after encoding: An event related potential study of familiarity and recollection in volunteers 
Anesthesiology  2009;110(2):295-312.
Intravenous drugs active via gamma-aminobutyric acid receptors produce memory impairment during conscious sedation. Memory function was assessed using event related potentials (ERPs) while drug was present.
The continuous recognition task measured recognition of photographs from working (6 seconds) and long term (27 seconds) memory while ERPs were recorded from Cz (familiarity recognition) and Pz electrodes (recollection recognition). Volunteer participants received sequential doses of one of placebo (n=11), propofol 0.45 and 0.9 ug/ml (n=10), midazolam 20 and 40 ng/ml (n=12), thiopental 1.5 and 3 ug/ml (n=11), or dexmedetomidine 0.25 and 0.4 ng/ml (n=11). End of day yes/no recognition 225 minutes after the end of drug infusion tested memory retention of pictures encoded on the continuous recognition tasks.
Active drugs increased reaction times and impaired memory on the continuous recognition task equally, except for a greater effect of midazolam (p<0.04). Forgetting from continuous recognition tasks to end of day was similar for all drugs (p=0.40), greater than placebo (p<0.001). Propofol and midazolam decreased the area between first presentation (new) and recognized (old, 27 seconds later) ERP waveforms from long term memory for familiarity (p=0.03) and possibly for recollection processes (p=0.12). Propofol shifted ERP amplitudes to smaller voltages (p<0.002). Dexmedetomidine may have impaired familiarity more than recollection processes (p=0.10). Thiopental had no effect on ERPs.
Propofol and midazolam impaired recognition ERPs from long term, but not working memory. ERP measures of memory revealed different pathways to end of day memory loss as early as 27 seconds after encoding.
PMCID: PMC2735240  PMID: 19194157

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