Chih-Hung Chang

Northwestern University, Evanston, Illinois, United States

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Publications (43)111.05 Total impact

  • Denys T. Lau · Cheryl T. Coon · Brian Joyce · A. Simon Pickard · Chih-Hung Chang ·
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    ABSTRACT: OBJECTIVE: Managing medications for home hospice elderly patients is an important and complex responsibility for informal (unpaid) caregivers. This study reports the interim results on the development of a new instrument to measure informal caregiving skills in effective medication management (CG-SEMM) for hospice patients. METHODS: Interim results are based on 60 informal caregivers with medication responsibilities from 5 hospice agencies in Chicagoland. The piloted CG-SEMM instrument contains 52 objectively-measured skill items hypothesized to capture 5 conceptual domains: teamwork, organization, medications, symptoms, and personhood. Additionally, 5 self-rated skill items, one corresponding to each domain, were assessed. To examine the structure of each domain, principal components analysis, exploratory factor analyses, internal consistency, and item response theory were examined. RESULTS: The 5 self-rated skill items appear to function as a unidimensional scale that measures caregiver self-efficacy in managing medications (factor loadings=0.55-0.84; alpha=0.84). Among the 52 objectively-measured skill items, there appears to be one organization domain related to how medication information should be recorded (factor loadings=0.51-0.79; Cronbach's coefficient alpha=0.74) and one medications domain related to understanding basics of pharmacology and medication administration (factor loadings=0.37-0.67; alpha=0.70). Item response theory informed the scoring of the response categories and the appropriateness of these items for identifying caregivers who could benefit from training. Structures for teamwork, personhood, and symptoms domains are inconclusive; additional subject recruitment and scale refinement are needed. CONCLUSION: Interim findings suggest that the CG-SEMM instrument may be a promising, psychometrically-valid tool for assessing caregiving skills necessary for managing medications effectively in hospice patients.
    139st APHA Annual Meeting and Exposition 2011; 11/2011
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    ABSTRACT: We sought to develop and validate a novel palliative medicine needs assessment tool for patients with cancer in the emergency department. An expert panel trained in palliative medicine and emergency medicine reviewed and adapted a general palliative medicine symptom assessment tool, the Needs at the End-of-Life Screening Tool. From this adaptation a new 13-question instrument was derived, collectively referred to as the Screen for Palliative and End-of-life care needs in the Emergency Department (SPEED). A database of 86 validated symptom assessment tools available from the palliative medicine literature, totaling 3011 questions, were then reviewed to identify validated test items most similar to the 13 items of SPEED; a total of 107 related questions from the database were identified. Minor adaptations of questions were made for standardization to a uniform 10-point Likert scale. The 107 items, along with the 13 SPEED items were randomly ordered to create a single survey of 120 items. The 120-item survey was administered by trained staff to all patients with cancer who met inclusion criteria (age over 21 years, English-speaking, capacity to provide informed consent) who presented to a large urban academic emergency department between 8:00 am and 11:00 pm over a 10-week period. Data were analyzed to determine the degree of correlation between SPEED items and the related 107 selected items from previously validated tools. A total of 53 subjects were enrolled, of which 49 (92%) completed the survey in its entirety. Fifty-three percent of subjects were male, age range was 24-88 years, and the most common cancer diagnoses were breast, colon, and lung. Cronbach coefficient α for the SPEED items ranged from 0.716 to 0.991, indicating their high scale reliability. Correlations between the SPEED scales and related assessment tools previously validated in other settings were high and statistically significant. The SPEED instrument demonstrates reliability and validity for screening for palliative care needs of patients with cancer presenting to the emergency department.
    Journal of palliative medicine 06/2011; 14(6):757-64. DOI:10.1089/jpm.2010.0456 · 1.91 Impact Factor
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    ABSTRACT: A comprehensive whole-person approach might improve processes and outcomes of care for patients with cancer. To assess the ability of NEST13+ (Needs of a social nature; Existential concerns; Symptoms; and Therapeutic interaction), a screening and assessment tool, to identify social, emotional, physical, and care-system needs and to improve clinical outcomes for cancer patients in tertiary care. A controlled trial involving 451 patients hospitalized for cancer care at a comprehensive cancer center. Patients responded to 13 screening questions regarding possible care needs. When an individual response exceeded threshold levels, additional in-depth questions for the relevant need were asked. For patients in the intervention arm, clinical recommendations for each dimension of need were generated based on a previously developed NEST-response-driven menu, and were reported to the clinical team. Documented needs, clinician response, patient perception of goals alignment, and overall quality of palliative care. Using the NEST13+ tool in the clinical setting facilitated greater documentation of illness-related needs than routine clinical assessment. Improvement in secondary outcomes was attenuated: changes in the clinician response were modest; changes in outcomes were not significant. The NEST13+ tool facilitated identification of a wider range of important needs than traditional evaluation, while care outcomes were not improved. Traditional evaluation may need improvement. Future trials of the NEST13+ should focus on more intensive clinician-directed interventions.
    Journal of palliative medicine 10/2009; 13(2):161-9. DOI:10.1089/jpm.2009.0170 · 1.91 Impact Factor
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    ABSTRACT: To propose a theoretical construct of family caregiver skills in effective medication management for home hospice patients. Semistructured face-to-face interviews were conducted with 22 hospice providers (14 nurses, 4 physicians, and 4 social workers) and 23 family caregivers (10 daughters, 4 wives, 2 husbands, and 7 others) of elderly patients (>or=60 years old) who were receiving home services from four hospice care programs in the Chicago metropolitan area. Although both groups identified similar skill sets, hospice providers emphasized technical skills such as administering medications, and family caregivers valued management skills such as organizing medications, coordinating with hired caregivers, and providing care to patients who resisted treatment. We defined effective medication management in hospice as caregivers' ability to effectively relieve symptoms with pharmacological interventions by successfully utilizing skills related to teamwork (coordinate with hospice providers and with other family or hired caregivers), organization (acquire, store, track, and discard medications), symptom knowledge (recognize and interpret common symptoms), medication knowledge (understand the basics of pharmacology and medication administration), and personhood (understand and respond to the patient's needs). The proposed construct of medication management skills in hospice will help guide future development of training interventions and clinical assessment tools.
    The Journals of Gerontology Series B Psychological Sciences and Social Sciences 06/2009; 64(6):799-807. DOI:10.1093/geronb/gbp033 · 3.21 Impact Factor
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    ABSTRACT: Objectives: An emerging issue in the proxy literature is whether specifying different proxy viewpoints contributes to different health-related quality of life (HRQL) assessments, and if so, how might each perspective be informative in medical decision making. The aims of this study were to determine if informal caregiver assessments of patients with prostate cancer differed when prompted from both the patient perspective (proxy-patient) and their own viewpoint (proxy-proxy), and to identify factors associated with differences in proxy perspectives (ie, the intraproxy gap). Research Design and Methods: Using a cross-sectional design, prostate cancer patients and their informal caregivers were recruited from urology clinics in the Jesse Brown Veterans Affairs Healthcare System in Chicago. Dyads assessed HRQL using the EQ-5D visual analog scale (VAS) and EORTC QLQ-C30. Results: Of 87 dyads, most caregivers were female (83%) and were spouses/partners (58%). Mean difference scores between proxy-patient and proxy-proxy perspectives were statistically significant for QLQ-C30 physical and emotional functioning, and VAS (all P < 0.05), with the proxy-patient perspective closer to patient self-report. Emotional functioning had the largest difference, mean 6.0 (SD 12.8), an effect size = 0.47. Factors weakly correlated with the intraproxy gap included relationship (spouse) and proxy gender for role functioning, and health literacy (limited/functional) for physical functioning (all P < 0.05, 0.20 < r < 0.35). Conclusions: Meaningful differences between proxy-patient and proxy-proxy perspectives on mental health were consistent with a conceptual framework for understanding proxy perspectives. Prompting different proxy viewpoints on patient health could help clinicians identify patients who may benefit from clinical intervention.
    Medical Care 01/2009; 47(2):176-183. DOI:10.1097/MLR.0b013e31818475f4 · 3.23 Impact Factor
  • Chih-Hung Chang · Chris M Gonzalez · Denys T Lau · Herbert C Sier ·
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    ABSTRACT: To examine the prevalence and management of urinary incontinence (UI) and their impact on self-reported health in the U.S. Medicare managed care beneficiaries. Data were from the 2003 Medicare Health Outcomes Survey Cohort VI Baseline. Only beneficiaries aged 65 years or older and who self-completed the telephone interview were included. About 37% of the study sample (N = 82,196) reported having accidental urine leakage (the UI group). A total of 75% of the UI group indicated UI's being a problem and 41% of them had spoken with a doctor about it. Of these, 50% had received treatment. The findings indicate the UI group generally had significantly worse SF-36 Survey Scale scores than the non-UI group with and without adjusting other covariates. UI is prevalent but undertreated as it adversely affects many health domains in this population. This study highlights the need for early detection, proper education, and access to effective treatment options for UI in the elderly.
    Journal of Aging and Health 07/2008; 20(4):405-19. DOI:10.1177/0898264308315853 · 1.56 Impact Factor
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    ABSTRACT: To evaluate scalability of a symptom scale administered to women enrolled in the Breast Cancer Prevention Trial (BCPT) (P-1) conducted by the National Surgical Adjuvant Breast and Bowel Project (NSABP). Responses of 11,064 women recruited into a study of 20 mg daily tamoxifen versus placebo to prevent breast cancer in high-risk women were analyzed. Exploratory factor analyses of the 12 month data were conducted on a random subset of 4,000 women to estimate the factor structure. Baseline data on these same 4,000 women were analyzed to confirm the structure. The remaining sample was divided randomly into two data sets. Data on each set were then grouped by age (35-49, 50-59, or > or = 60 years) and treatment (tamoxifen or placebo) to corroborate these analyses. Correlations between the obtained symptom clusters and two standard instruments (SF-36 and CES-D) were examined. Content analysis of open-ended responses was also conducted. Eight clinically-interpretable clusters of symptoms were identified and confirmed: Cognitive symptoms, musculoskeletal pain, vasomotor symptoms, nausea, sexual problems, bladder problems, body image, and vaginal symptoms. Scoring for each scale represented by these eight clusters is provided. Content analysis of open-ended responses suggested four items that are additional candidates: fatigue, back problems, abdominal pain, and leg/foot cramps or pain. Symptoms associated with hormone therapy for breast cancer can vary. Nevertheless, the BCPT Eight Symptom Scale (BESS) can be clustered into clinically relevant and reproducible factors that may be useful in future outcomes research.
    Breast Cancer Research and Treatment 06/2008; 109(3):515-26. DOI:10.1007/s10549-007-9682-9 · 3.94 Impact Factor
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    ABSTRACT: A concise yet accurate measurement tool is needed for use in research and practice in asthma self-management perceptions across culturally diverse patient populations. To evaluate the psychometric properties of the 11-item Perceived Control of Asthma Questionnaire (PCAQ) and to derive a brief, psychometrically sound, and culturally sensitive measure using item response theory. The PCAQ was administered as one of a battery of measures to 375 adults with asthma as part of an ongoing larger project studying asthma disparities. Analyses of differential item functioning (DIF) were conducted to detect the effects of sex, race/ethnicity, and health literacy on psychometric properties. Forty-eight percent of the sample was non-Hispanic white and 44% was African American. The mean +/- SD age was 43.7 +/- 13.7 years. The derived 6-item version, with 5 DIF items not scored, correlated highly with its full version (r = 0.903; P < .001). The 6-item PCAQ short form has the potential to maintain scale integrity while reducing administration time and lessening survey fatigue in studies using multiple questionnaires. DIF analyses also enabled us to understand the unique aspects of perceived asthma control in demographic groups most affected by asthma.
    Annals of allergy, asthma & immunology: official publication of the American College of Allergy, Asthma, & Immunology 08/2007; 99(2):130-5. DOI:10.1016/S1081-1206(10)60636-9 · 2.60 Impact Factor
  • Bryce B. Reeve · Ron D. Hays · Chih-Hung Chang · Eleanor M. Perfetto ·

    Quality of Life Research 07/2007; 16:1-3. DOI:10.1007/s11136-007-9220-6 · 2.49 Impact Factor
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    ABSTRACT: The availability of psychometrically sound and clinically relevant screening, diagnosis, and outcome evaluation tools is essential to high-quality palliative care assessment and management. Such data will enable us to improve patient evaluations, prognoses, and treatment selections, and to increase patient satisfaction and quality of life. To accomplish these goals, medical care needs more precise, efficient, and comprehensive tools for data acquisition, analysis, interpretation, and management. We describe a system for interactive assessment and management in palliative care (SIAM-PC), which is patient centered, model driven, database derived, evidence based, and technology assisted. The SIAM-PC is designed to reliably measure the multiple dimensions of patients' needs for palliative care, and then to provide information to clinicians, patients, and the patients' families to achieve optimal patient care, while improving our capacity for doing palliative care research. This system is innovative in its application of the state-of-the-science approaches, such as item response theory and computerized adaptive testing, to many of the significant clinical problems related to palliative care.
    Journal of Pain and Symptom Management 07/2007; 33(6):745-55. DOI:10.1016/j.jpainsymman.2006.09.018 · 2.80 Impact Factor
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    Lisa K Sharp · Linda G Kimmel · Romina Kee · Carol Saltoun · Chih-Hung Chang ·
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    ABSTRACT: The Perceived Stress Scale (PSS) is a widely used measure of stress that has not been validated in asthma patients. The psychometric properties of the PSS were explored using confirmatory factor analysis and item response theory. Study 1 involved 312 ambulatory care patients with asthma who completed the PSS during a routine visit. Study 2 involved 247 community-dwelling adults with asthma who completed the PSS as a part of a larger asthma study. Four items showed acceptable psychometric performance across ethnic groups and literacy. The short PSS is a rapid, valid measure of subjective stress in diverse asthma populations.
    Journal of Asthma 06/2007; 44(4):311-6. DOI:10.1080/02770900701344165 · 1.80 Impact Factor
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    ABSTRACT: In June 2004, the National Cancer Institute and the Drug Information Association co-sponsored the conference, "Improving the Measurement of Health Outcomes through the Applications of Item Response Theory (IRT) Modeling: Exploration of Item Banks and Computer-Adaptive Assessment." A component of the conference was presentation of a psychometric and content analysis of a secondary dataset. A thorough psychometric and content analysis was conducted of two primary domains within a cancer health-related quality of life (HRQOL) dataset. HRQOL scales were evaluated using factor analysis for categorical data, IRT modeling, and differential item functioning analyses. In addition, computerized adaptive administration of HRQOL item banks was simulated, and various IRT models were applied and compared. The original data were collected as part of the NCI-funded Quality of Life Evaluation in Oncology (Q-Score) Project. A total of 1,714 patients with cancer or HIV/AIDS were recruited from 5 clinical sites. Items from 4 HRQOL instruments were evaluated: Cancer Rehabilitation Evaluation System-Short Form, European Organization for Research and Treatment of Cancer Quality of Life Questionnaire, Functional Assessment of Cancer Therapy and Medical Outcomes Study Short-Form Health Survey. Four lessons learned from the project are discussed: the importance of good developmental item banks, the ambiguity of model fit results, the limits of our knowledge regarding the practical implications of model misfit, and the importance in the measurement of HRQOL of construct definition. With respect to these lessons, areas for future research are suggested. The feasibility of developing item banks for broad definitions of health is discussed.
    Quality of Life Research 02/2007; 16 Suppl 1(S1):121-32. DOI:10.1007/s11136-007-9177-5 · 2.49 Impact Factor
  • Chih-Hung Chang ·
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    ABSTRACT: Successful integration of modern psychometrics and advanced informatics in patient-reported outcomes (PRO) measurement and management can potentially maximize the value of health outcomes research and optimize the delivery of quality patient care. Unlike the traditional labor-intensive paper-and-pencil data collection method, item response theory-based computerized adaptive testing methodologies coupled with novel technologies provide an integrated environment to collect, analyze and present ready-to-use PRO data for informed and shared decision-making. This article describes the needs, challenges and solutions for accurate, efficient and cost-effective PRO data acquisition and dissemination means in order to provide critical and timely PRO information necessary to actively support and enhance routine patient care in busy clinical settings.
    Quality of Life Research 02/2007; 16 Suppl 1(S1):157-66. DOI:10.1007/s11136-007-9196-2 · 2.49 Impact Factor
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    Jakob Bue Bjorner · Chih-Hung Chang · David Thissen · Bryce B Reeve ·
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    ABSTRACT: Item banks and Computerized Adaptive Testing (CAT) have the potential to greatly improve the assessment of health outcomes. This review describes the unique features of item banks and CAT and discusses how to develop item banks. In CAT, a computer selects the items from an item bank that are most relevant for and informative about the particular respondent; thus optimizing test relevance and precision. Item response theory (IRT) provides the foundation for selecting the items that are most informative for the particular respondent and for scoring responses on a common metric. The development of an item bank is a multi-stage process that requires a clear definition of the construct to be measured, good items, a careful psychometric analysis of the items, and a clear specification of the final CAT. The psychometric analysis needs to evaluate the assumptions of the IRT model such as unidimensionality and local independence; that the items function the same way in different subgroups of the population; and that there is an adequate fit between the data and the chosen item response models. Also, interpretation guidelines need to be established to help the clinical application of the assessment. Although medical research can draw upon expertise from educational testing in the development of item banks and CAT, the medical field also encounters unique opportunities and challenges.
    Quality of Life Research 02/2007; 16 Suppl 1(S1):95-108. DOI:10.1007/s11136-007-9168-6 · 2.49 Impact Factor
  • David Thissen · Bryce B Reeve · Jakob Bue Bjorner · Chih-Hung Chang ·
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    ABSTRACT: This paper reviews important methodological considerations for developing item banks and computerized adaptive scales (commonly called computerized adaptive tests in the educational measurement literature, yielding the acronym CAT), including issues of the reference population, dimensionality, dichotomous versus polytomous response scales, differential item functioning (DIF) and conditional scoring, mode effects, the impact of local dependence, and innovative approaches to assessment using CATs in health outcomes research.
    Quality of Life Research 02/2007; 16 Suppl 1(S1):109-19. DOI:10.1007/s11136-007-9169-5 · 2.49 Impact Factor
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    Sheila Perry · Theresa L Kowalski · Chih-Hung Chang ·
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    ABSTRACT: In 2006, breast cancer was the third leading cause of death in American women; however, more women survive breast cancer than any other type of cancer. As the disease progresses, it is important to know how one's health-related quality of life (QOL) is affected for those who receive treatment, those who survive, and those who remain disease-free. The purpose of this study was to summarize the benefits, challenges, and barriers of QOL measurement for female breast cancer patients. A PubMed literature search was conducted using the terms "quality of life" and "breast cancer." The search was then refined with terms related to QOL assessment instruments. The research team reviewed over 100 of the 2,090 articles identified. From the results, a detailed outline of QOL instruments is presented, and the effectiveness of QOL instruments is discussed. In the current literature review, both generic and breast cancer specific QOL instruments, examining computerized and paper-and-pencil versions, are explained as well as the advantages, acceptability, and problems of these assessments. Potential barriers to implementation are also discussed. The implementation of QOL assessment tools in breast cancer clinical practice is discussed, with evidence detailing how such tools would benefit patients.
    Health and Quality of Life Outcomes 02/2007; 5(1):24. DOI:10.1186/1477-7525-5-24 · 2.12 Impact Factor
  • Chih-Hung Chang · Benjamin D Wright · David Cella · Ron D Hays ·
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    ABSTRACT: This study assesses the extent to which the RAND-36/SF-36 items measure physical and mental health (PH and MH), as implied by existing summary scoring systems. A total of 1,714 heterogeneous cancer and HIV/AIDS patients were recruited from five institutions. Of these, 56% were women; 81% Caucasians; and about 10% were from each of the major cancer types and HIV/AIDS. Analyses of the SF-36 confirmed the two dimensions of health namely physical and mental. However, item fit statistics and residual factor analysis revealed that some items intended to represent the PH dimension fit better with the MH dimension. This paper demonstrated the value of Rasch residual factor analysis for understanding and enhancing interpretation of health.
    Journal of Clinical Epidemiology 02/2007; 60(1):68-72. DOI:10.1016/j.jclinepi.2006.07.001 · 3.42 Impact Factor
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    ABSTRACT: To develop and validate multiattribute measures for patients with rheumatoid arthritis (RA) to report health states and estimate preference weights. Survey materials were mailed to 748 patients. Factor analysis, an item response theory-based model, and an internal consistency test were used to identify attributes and evaluate items. Two multiattribute preference weight functions (MAPWF) were constructed. Construct validity of the new measures was then tested. Four hundred eighty-seven patients returned the survey; 24 items on 6 health attributes were selected to form the new outcomes measure. Two MAPWF were derived with preference weights measured with time tradeoff and visual analog scales as dependent variables. All validity test results were statistically significant. Our results reveal that the new measures are reliable and valid in assessing health states and associated preference weights of patients with RA.
    The Journal of Rheumatology 01/2007; 33(12):2409-11. · 3.19 Impact Factor
  • Sarah Gehlert · Chih-Hung Chang · R Darrell Bock · S Ann Hartlage ·
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    ABSTRACT: The Women's Quality of Life Questionnaire (WOMQOL) was developed to measure aspects of the health of women of reproductive age with no known pathology. Five experts in women's health and mental health rated a pool of 140 items as very significant, somewhat significant, or insignificant to women's health. Sixty-seven items were retained and formatted as a self-reported questionnaire with dichotomous responses to each statement ("true" and "false"). A total of 1,207 women completed the instrument during the follicular and late luteal phases of their menstrual cycles. Dichotomous response data from the follicular phases were analyzed using item response theory-based full-information item factor analysis to identify interpretable factors. Measurement invariance of the obtained factors across cycle phases and age cohorts was further evaluated using differential item functioning (DIF). Four primary factors, made up of the 10 items with highest factor loading in each factor, were found to measure physical, mental, social, and spiritual health. No items were found to display DIF across the phases of menstrual cycles or age cohorts. Although additional studies of diverse groups of women are advised, the final 40-item WOMQOL is a psychometrically sound measure that can be used to evaluate the quality of life of women of reproductive age in the general population.
    Journal of Clinical Epidemiology 06/2006; 59(5):525-33. DOI:10.1016/j.jclinepi.2005.09.008 · 3.42 Impact Factor
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    ABSTRACT: Although clinicians and researchers often rely on family members 'reports of a wide range of dying patients' symptoms and care preferences, available data indicate divergences between the two. We used a national sample to analyze patient-caregiver pairs to explore areas of concordance and nonconcordance about physical symptoms, communication with physicians, caregiving needs, and future fears. We also assessed whether identifiable patient or caregiver characteristics were associated with nonconcordance. Our data were from a national, random sample of 988 terminally ill patients, of whom 893 had caregivers who were also interviewed. Frequencies and types of nonconcordance were computed for patient-caregiver pairs. Bivariate associations between patient and caregiver reports on each item were tested. Logistic and conditional logistic regression analyses assessed multiple predictors of nonconcordance for each item. Primary diagnoses included cancer (51.1 percent), heart disease (17. 7 percent), chronic obstructive pulmonary disease (10. 7 percent), and other diseases (20.5 percent). The proportion of concordant reports among pairs of patients and caregivers ranged from 53 percent to 66 percent. Among pairs showing nonconcordant responses, caregivers reported higher levels of pain and disability than patients, lower caregiving needs, and different fears about the future. Few demographic or clinical predictors were associated with nonconcordance. Concordance between patients 'and their caregivers' responses ranged widely, and there were important areas of nonconcordant responses. When responses differed, patients were more likely to express concern about domains that might impose on caregivers, while caregivers were more likely to express concern about patients 'physical suffering. Consistent sociodemographic or clinical predictors of nonconcordant responses were not found. These data suggest important ways that patient and caregiver reports of the same experience vary.
    American Journal of Hospice and Palliative Medicine 03/2006; 23(2):105-12. DOI:10.1177/104990910602300207 · 1.38 Impact Factor

Publication Stats

2k Citations
111.05 Total Impact Points


  • 2003-2011
    • Northwestern University
      • • Division of Gastroenterology and Hepatology
      • • Feinberg School of Medicine
      • • Division of Hospital Medicine
      Evanston, Illinois, United States
  • 2008
    • National Surgical Adjuvant Breast and Bowel Project
      Pittsburgh, Pennsylvania, United States