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Biomedical subjects

J E Ware

Publications and source records attributed to J E Ware.

At least 19 recordsLinked to original sources
PubMed2003

The responsiveness of headache impact scales scored using 'classical' and 'modern' psychometric methods: a re-analysis of three clinical trials.

BACKGROUND: While item response theory (IRT) offers many theoretical advantages over classical test theory in the construction and scoring of patient based measures of health few studies compare scales constructed from both methodologies head to head. OBJECTIVE: Compare the responsiveness to treatment of migraine specific scales scored using summated rating scale methods vs. IRT methods. METHODS: The data came from three clinical studies of migraine treatment that used the Migraine Specific Quality of Life Questionnaire (MSQ). Five methods of quantifying responsiveness were used to evaluate and compare changes from pre- to post-treatment in MSQ scales scored using Likert and IRT scaling methods. RESULTS: Changes in all MSQ scale scores from pre- to post-treatment were highly significant in all three studies. A single index scored from the MSQ using IRT methods was determined to be more responsive than any one of the MSQ subscales across the five methods used to quantify responsiveness. Across 13 of the 15 tests (5 responsiveness methods * 3 studies) conducted, the single index scored from the MSQ using IRT methods was the most responsive measure. CONCLUSIONS: IRT methods increased the responsiveness of the MSQ to the treatment of migraine. The results agree with the psychometric evidence that suggest that it is feasible to score a single index from the MSQ using IRT methods. This approach warrants further testing with other measures of migraine impact.

Adult↗
PubMed2003

A six-item short-form survey for measuring headache impact: the HIT-6.

BACKGROUND: Migraine and other severe headaches can cause suffering and reduce functioning and productivity. Patients are the best source of information about such impact. OBJECTIVE: To develop a new short form (HIT-6) for assessing the impact of headaches that has broad content coverage but is brief as well as reliable and valid enough to use in screening and monitoring patients in clinical research and practice. METHODS: HIT-6 items were selected from an existing item pool of 54 items and from 35 items suggested by clinicians. Items were selected and modified based on content validity, item response theory (IRT) information functions, item internal consistency, distributions of scores, clinical validity, and linguistic analyses. The HIT-6 was evaluated in an Internet-based survey of headache sufferers (n = 1103) who were members of America Online (AOL). After 14 days, 540 participated in a follow-up survey. RESULTS: HIT-6 covers six content categories represented in widely used surveys of headache impact. Internal consistency, alternate forms, and test-retest reliability estimates of HIT-6 were 0.89, 0.90, and 0.80, respectively. Individual patient score confidence intervals (95%) of app. +/-5 were observed for 88% of all respondents. In tests of validity in discriminating across diagnostic and headache severity groups, relative validity (RV) coefficients of 0.82 and 1.00 were observed for HIT-6, in comparison with the Total Score. Patient-level classifications based in HIT-6 were accurate 88.7% of the time at the recommended cut-off score for a probability of migraine diagnosis. HIT-6 was responsive to self-reported changes in headache impact. CONCLUSIONS: The IRT model estimated for a 'pool' of items from widely used measures of headache impact was useful in constructing an efficient, reliable, and valid 'static' short form (HIT-6) for use in screening and monitoring patient outcomes.

Adult↗
PubMed2001

The effects of interferon alpha-2b in combination with ribavirin on health related quality of life and work productivity.

BACKGROUND/AIMS: Interferon plus ribavirin is the most effective therapy for chronic hepatitis C. The aim of this study was to evaluate the effect of chronic hepatitis C and therapy on health-related quality of life and work functioning. METHODS: Nine hundred and twelve patients with hepatitis C infection were randomized in a controlled trial of Interferon alpha 2b 3 MU tiw for 24 or 48 weeks plus ribavirin 1000-1200 mg or placebo. Questionnaire-based assessments of health-related quality of life and work functioning were performed before, during, and after treatment. Outcome measures included the SF-36 Health Survey and additional generic and specific scales. Work functioning was assessed as missed days, shorter hours or less productivity at work. RESULTS: Pre-treatment, patients had significant impairment in five of eight SF-36 concepts compared to matched population norms. Sustained responders had a return to normal for four of these five concepts. Quality of life did not improve in non-responders. Improvements in histology, viral load or ALT values predicted improvements in quality of life. Sustained responders also had improvements in work functioning and productivity. CONCLUSIONS: Hepatitis C patients had impaired quality of life. After combination therapy, sustained virologic responders achieved benefits in their quality of life and work functioning.

Adult↗
PubMed2001

Sleep problems, health-related quality of life, work functioning and health care utilization among the chronically ill.

OBJECTIVES: To provide a comprehensive assessment of whether sleep problems among the chronically ill are associated with decrements in functional health and well-being, decreases in work functioning and increases in the use of health care services. DESIGN: Cross-sectional survey of patients from the Medical Outcomes Study (MOS), an observational study of functional health and well-being. Chronically ill patients (n = 3484) were sampled from health maintenance organizations, large multi-specialty groups, and solo or single-specialty group practices in Boston, Los Angeles, and Chicago. Chronic illness subgroups include: clinical depression (n = 527), congestive heart failure (229), diabetes (n = 577), recent myocardial infarction (n = 170), hypertension (n = 2206), asthma (n = 84), back problems (n = 771), and arthritis (n = 672). ANCOVA analyses of the relationship between sleep problems and SF-36 scales and summaries were performed. In addition, a 'relative impact' analysis determined what scales or summaries were most associated with sleep problems. MAIN OUTCOME MEASURES: Eight scales and two summary measures from the SF-36 Health Survey, work productivity and work quality measures and self-reports of health care utilization. RESULTS: Comparing chronically ill patients with no sleep problems to those with mild, moderate, or severe sleep problems revealed a direct association between sleep problems and decrements in health-related quality of life (HRQOL) as measured by SF-36 scales and summaries (MANOVA F 24.1; d.f. 24; p < or = 0.0001). In addition, significant differences in HRQOL were found when comparing patients with and without sleep problems within most of the disease groups studied. The relative impact analysis revealed that measures of mental health and the mental health summary were most associated with sleep problem severity in the total sample and chronic disease subsets, in comparison with measures of physical health. In addition, monotonic relationships were found between severity of sleep problems and decreases in work productivity and increases in health care utilization, as expected. CONCLUSIONS: The analyses revealed that sleep problems go hand in hand with poorer mental health, diminished work productivity and work quality and greater use of health care services. Sleep problems, therefore, may be a significant confounding factor in the interpretation of health outcomes among patients with chronic diseases.

Adult↗
PubMed2001

Interpreting SF-36 summary health measures: a response.

In response to questions raised about the "accuracy" of SF-36 physical (PCS) and mental (MCS) component summary scores, particularly extremely high and low scores, we briefly comment on: how they were developed, how they are scored, the factor content of the eight SF-36 subscales, cross-tabulations between item-level responses and extreme summary scores, and published and new tests of their empirical validity. Published cross-tabulations between SF-36 items and PCS and MCS scores, reanalyses of public datasets (N = 5919), and preliminary results from the Medicare Health Outcomes Survey (HOS) (N = 172,314) yielded little or no evidence in support of Taft's hypothesis that extreme scores are an invalid artifact of some negative scoring weights. For example, in the HOS, those (N = 432) with "unexpected" PCS scores worse than 20 (which, according to Taft, indicate better mental health rather than worse physical health) were about 25% more likely to die within two years, in comparison with those scoring in the next highest (21-30) category. In this test and in all other empirical tests, results of predictions supported the validity of extreme PCS and MCS scores. We recommend against the interpretation of average differences smaller than one point in studies that seek to detect "false" measurement and we again repeat our 7-year-old recommendation that results based on summary measures should be thoroughly compared with the SF-36 profile before drawing conclusions. To facilitate such comparisons, scoring utilities and user-friendly graphs for SF-36 profiles and physical and mental summary scores (both orthogonal and oblique scoring algorithms) have been made available on the Internet at www.sf-36.com/test.

Factor Analysis, Statistical↗
PubMed2000

Organizational and financial characteristics of health plans: are they related to primary care performance?

BACKGROUND: Primary care performance has been shown to differ under different models of health care delivery, even among various models of managed care. Pervasive changes in our nation's health care delivery systems, including the emergence of new forms of managed care, compel more current data. OBJECTIVE: To compare the primary care received by patients in each of 5 models of managed care (managed indemnity, point of service, network-model health maintenance organization [HMO], group-model HMO, and staff-model HMO) and identify specific characteristics of health plans associated with performance differences. METHODS: Cross-sectional observational study of Massachusetts adults who reported having a regular personal physician and for whom plan-type was known (n = 6018). Participants completed a validated questionnaire measuring 7 defining characteristics of primary care. Senior health plan executives provided information about financial and nonfinancial features of the plan's contractual arrangements with physicians. RESULTS: The managed indemnity system performed most favorably, with the highest adjusted mean scores for 8 of 10 measures (P<.05). Point of service and network-model HMO performance equaled the indemnity system on many measures. Staff-model HMOs performed least favorably, with adjusted mean scores that were lowest or statistically equivalent to the lowest score on all 10 scales. Among network-model HMOs, several features of the plan's contractual arrangement with physicians (ie, capitated physician payment, extensive use of clinical practice guidelines, financial incentives concerning patient satisfaction) were significantly associated with performance (P<.05). CONCLUSIONS: With US employers and purchasers having largely rejected traditional indemnity insurance as unaffordable, the results suggest that the current momentum toward open-model managed care plans is consistent with goals for high-quality primary care, but that the effects of specific financial and nonfinancial incentives used by plans must continue to be examined.

Adult↗
PubMed2000

Determining minimally important changes in generic and disease-specific health-related quality of life questionnaires in clinical trials of rheumatoid arthritis.

OBJECTIVE: To define clinically meaningful changes in 2 widely used health-related quality of life (HQL) instruments in studies of patients with rheumatoid arthritis (RA). METHODS: Patients with RA (n = 693) who were enrolled in 2 double-blind, placebo-controlled clinical trials completed the Short Form 36 (SF-36) modified health survey and the Health Assessment Questionnaire (HAQ) disability index at baseline and 6-week followup assessments. Data on 5 RA severity measures were also collected at baseline and at 6 weeks (patient and physician global assessments, joint swelling and tenderness counts, and global pain assessment). Comparison of changes in the SF-36 scales and HAQ scores was made between groups of patients known to differ in the level of change on each RA severity measure. RESULTS: With few exceptions, changes in the SF-36 and HAQ scores were different between patients who differed in the level of change on each RA severity measure. Changes in the SF-36 and HAQ scores were more strongly related to changes in the patient and physician global assessments and patient pain assessment than to changes in the joint swelling and tenderness counts. CONCLUSION: Based on these results, minimally important changes in the SF-36 scales and HAQ disability scores were determined, which will be useful in interpreting HQL results in clinical trials.

Adult↗
PubMed2000

A new tool for monitoring asthma outcomes: the ITG Asthma Short Form.

BACKGROUND: Asthma treatment has broadened from managing clinical markers to incorporate factors that are most meaningful to patients, collectively called health-related quality of life (HQL). OBJECTIVE: To develop an asthma-specific HQL tool, meeting demands for brevity, usefulness and measurement precision. METHODS: The 20-item Sydney Asthma Quality of Life Questionnaire (AQLQ) and six additional items were studied using factor analysis, reliability and validity tests among asthma patients 14 and older. RESULTS: The 15-item Integrated Therapeutics Group Asthma Short Form (ITG-ASF) retains the validity of the AQLQ with improved scaling properties and interpretability. The ITG-ASF yields 6 scores: Symptom-Free Index, Functioning with Asthma, Psychosocial Impact of Asthma, Asthma Energy and Asthma-Confidence in Health and a Total. All items correlated 0.40 or higher with their hypothesized scales and passed discriminant validity tests, with scaling success rates from 75 to 100%. Reliability exceeded the minimum of 0.70 for group comparisons. Ceiling and floor effects were acceptable. Scales were valid in relation to changes in asthma severity and lung function. The best predictor of asthma severity (National Asthma Education and Prevention Program (NAEPP) staging) was the Symptom-Free Index. A Spanish translation is available, Chinese-American is forthcoming. The reading grade level is 4.8. CONCLUSIONS: Development of the ITG-ASF was a data-driven process maximizing measurement precision and breadth while minimizing burden. The ITG-ASF is a brief, comprehensive and empirically valid tool that complements traditional markers of the outcomes of asthma care.

Adolescent↗
PubMed2000

Profile of men randomized to the prostate cancer prevention trial: baseline health-related quality of life, urinary and sexual functioning, and health behaviors.

PURPOSE: To describe men who agreed to be randomized to the Prostate Cancer Prevention Trial (PCPT), a 7-year, double-blind placebo-controlled study of the efficacy of finasteride in preventing prostate cancer. METHODS: Comprehensive health-related quality-of-life data are presented for 18,882 randomized PCPT participants. RESULTS: PCPT participants are highly educated, middle to upper income, and primarily white (92%). Participants reported healthy lifestyles. The mean American Urological Association Symptom Index score was well below the maximum entry score of less than 19; existing urinary symptoms were generally not bothersome. The scores for two sexual functioning scales could range from 0 to 100, with higher scores reflecting worse sexual functioning. The mean score for the Sexual Problem Scale was 19.2 out of 100, and the mean Sexual Activities Scale was 44.1 out of 100. Scores for seven of the eight Medical Outcomes Study 36-item Short-Form Health Survey scales (higher scores are better) were 10 to 20 points higher than those reported by a general population sample and differed minimally by race but not by age. Previously reported associations between sexual dysfunction and hypertension, diabetes, and depression were also observed. Men who never smoked reported less sexual dysfunction than did those who either had quit or still smoked. CONCLUSION: Individuals who are likely to enroll in primary prevention trials have a high socioeconomic status, healthy lifestyle behaviors, and better health than the general population. These data help oncologists design chemoprevention trials with respect to the selection of health-related quality-of-life assessments and recruitment strategies.

Aged↗
PubMed1999

Health-related quality of life in chronic hepatitis C: impact of disease and treatment response. The Interventional Therapy Group.

Hepatitis C infects nearly 4 million Americans. Most have chronic hepatitis C (CHC), which progresses to cirrhosis in about 20% of patients. Interferon treatment leads to transient responses in about 40% of patients and apparent eradication of infection in 7% to 40% of patients. In this report, we document the impact of CHC on health-related quality of life (HQL), and changes in HQL among treatment responders. Three hundred twenty-four CHC patients from 10 countries who had relapsed after responding to interferon-alfa therapy were randomized to monotherapy (IFN alfa-2b + placebo) or combination therapy (IFN alfa-2b + ribavirin), treated for 24 weeks, and followed up for 24 weeks. HQL was assessed using the Hepatitis Quality of Life Questionnaire (HQLQ), containing the generic SF-36 Health Survey, three additional generic scales, and two hepatitis-specific scales. Before treatment, CHC patients were impaired in 5 of 8 SF-36 concepts (physical functioning, role-physical, general health, vitality, and social functioning) in comparison with matched population norms. Sustained virological response (SVR) to treatment yielded improvements on three generic scales (vitality, social functioning, and health distress) and the CHC-specific health distress scale. Overall response to treatment (SVR plus histological improvement) yielded the same pattern of improvements with additional gains in generic general health and CHC-specific limitations. Successful treatment of CHC improved HQL as measured by both CHC-specific and generic measures of functional health and well being.

Female↗
PubMed1999

Monitoring health outcomes among patients with arthritis using the SF-36 Health Survey: overview.

As shown here, general health measures cover much of the content included in arthritis-specific measures, but, are they equally sensitive to changes in disease condition? We reviewed the literature on the most widely used general health measure, the SF-36 Health Survey, to see if the empirical evidence supported its validity for use in arthritis patients. As of this writing, there was no documentation of the sensitivity of the SF-36 to short-term changes in arthritic condition over the course of clinical trials and few studies that compared the sensitivity of the SF-36 to arthritis-specific measures. The empirical research reported in this special supplement contributes to the literature on the use of the SF-36 in arthritis patients and demonstrates methods of studying the validity of general health measures to monitor change in specific conditions.

Arthritis↗
PubMed1999

The SF-36 Health Survey as a generic outcome measure in clinical trials of patients with osteoarthritis and rheumatoid arthritis: tests of data quality, scaling assumptions and score reliability.

OBJECTIVE: To evaluate the psychometric assumptions underlying the construction and scoring of SF-36 scales and summary measures among clinical trial participants with arthritis. METHODS: Cross-sectional SF-36 data from the baseline assessment of adult patients (n = 1,016) participating in four placebo-controlled clinical trials of treatment for arthritis were analyzed with blinding as to treatment. Tests of the completeness of data, scaling assumptions, internal-consistency reliability, and factor structure of SF-36 scales were performed for the combined sample. Eligible participants had at least a 6-month history of moderate to severe osteoarthritis or rheumatoid arthritis of the knee or hip. Participants meeting inclusion criteria had undergone a washout period of 3-14 days before baseline assessment to bring about a flare state in osteoarthritis or rheumatoid arthritis symptoms. Baseline sample sizes for the three osteoarthritis trials were n = 121, n = 341, and n = 187. The baseline sample size for the rheumatoid arthritis trial was n = 367. The average age of participants was 60 years, and the majority were females (72%). Measured were functional health and well-being scales and physical and mental health summary measures from the SF-36 Health Survey acute form. RESULTS: Missing responses ranged from 0.0% to 1.5% across SF-36 items, and scale scores could be computed for 96.8% to 100% of participants across trials. In all four trials, item internal consistency tests were passed (91.4%-97.1%) and item discriminant validity tests were passed (96.9%-100.0%). Across the four trials, internal-consistency reliability coefficients ranged from a low of 0.75 to a high of 0.91 for the eight scales (median = 0.84), exceeding the minimum standards for group comparisons. Ceiling effects were minimal for most scales, and floor effects were noteworthy for the role physical and role emotional scales. Physical and mental health factors identified in previous studies were replicated. CONCLUSION: The SF-36 Health Survey proved to be a psychometrically sound tool for the assessment of the health status of adult participants in clinical trials of arthritis.

Adolescent↗
PubMed1999

The SF-36 Health Survey as a generic outcome measure in clinical trials of patients with osteoarthritis and rheumatoid arthritis: relative validity of scales in relation to clinical measures of arthritis severity.

OBJECTIVE: To evaluate the validity of SF-36 Health Survey (SF-36) scale scores and summary measure scores to describe the health burden of arthritis and to be responsive to clinical indicators of arthritis severity used in four clinical trials. METHODS: Adults participating in four double-blinded, placebo-controlled clinical trials of therapy for osteoarthritis or rheumatoid arthritis were administered the SF-36 concurrent with clinical measures of disease severity (n = 1,016). Data were collected before treatment and 2 weeks after treatment. Mean SF-36 scores for all patients with arthritis at baseline were compared to a sociodemographically equivalent national norm to test the ability of the SF-36 to describe the burden of arthritis. To test the responsiveness of SF-36 scores to clinical measures of arthritis severity, mean SF-36 scale scores were compared across patients differing in arthritis severity before treatment. Two-week mean SF-36 change scores were compared across patients who improved in arthritis severity (responders) versus patients who did not improve (nonresponders). F-statistics and relative validity coefficients were computed to determine how well each SF-36 scale and summary measure discriminated among arthritis severity levels and distinguished treatment responders from nonresponders, relative to the best scale. RESULTS: Large and statistically significant differences in mean SF-36 scale scores and summary measures were found such that trial participants scored in worse health than a sociodemographically equivalent US general population norm. In addition, the largest SF-36 scale scores were found to significantly differ across clinically defined levels of arthritis severity. Finally, it was found that the SF-36 scales that best discriminate among arthritis severity groups cross-sectionally were also best at discriminating treatment responders from nonresponders. CONCLUSION: Results of this study support the validity of the SF-36 to document the health burden of arthritis and as a measure of generic health outcome for clinical trials of alternative treatments for osteoarthritis and rheumatoid arthritis patients.

Adult↗
PubMed1999

The SF-36 Arthritis-Specific Health Index (ASHI): I. Development and cross-validation of scoring algorithms.

An arthritis-specific health index (ASHI) for the SF-36 Health Survey was developed by studying its responsiveness to changes in clinical indicators of arthritis severity. Longitudinal data from 1,076 patients participating in four placebo-controlled trials were analyzed. All had at least a 6-month history of moderate to severe osteoarthritis or rheumatoid arthritis of the knee or hip. All had undergone a washout period of 3 to 14 days before baseline assessment to bring about a flare state in osteoarthritis or rheumatoid arthritis symptoms. Their average age was 60 years and 72% were female. Change scores for the eight-scale SF-36 health profile (acute version) and five arthritis-specific measures of disease severity (knee pain on weight bearing, time to walk 50 feet, physician global evaluation of symptom severity and impact, patient global evaluation of symptom severity and impact, and pain intensity visual analogue scale) were computed by subtracting scores before treatment from scores at two-week follow-up. Canonical correlation methods were used to derive weights for changes in SF-36 scales to score a single index (ASHI) that maximized its correlation with changes in the set of five clinical measures of arthritis severity. The weights used to score the ASHI were cross-validated in a 25% holdout group (N = 144) from the first two osteoarthritis trials and in two additional osteoarthritis and rheumatoid arthritis trials (N = 530). Only one SF-36 canonical variate (ASHI) correlated significantly (F = 4.69, P < 0.0001) with the clinical canonical variate that served as the "criterion" measure of change in the severity of arthritis. Changes in the ASHI and clinical canonical variate were substantially correlated in the developmental sample (r = 0.628, P < 0.0001) and on cross-validation (r = 0.629, P < 0.0001). The clinical canonical variate correlated highly (r = 0.75-0.88) with changes in all but one of the five clinical measures (50-foot walk; r = 0.41). The pattern of correlations between changes in SF-36 scales and the ASHI indicated that ASHI is primarily a measure of bodily pain (r = 0.92) and other aspects of physical and role functioning and well-being (r = 0.69 for Role-Physical, r = 0.68 for Physical Functioning, r = 0.52 for Social Functioning, and r = 0.51 Vitality). The patterns of correlations between SF-36 scales and the ASHI were very similar across developmental and cross-validation samples. This research demonstrates the feasibility and generalizability of a single ASHI scored from changes in responses to the SF-36 Health Survey. The generic SF-36 health profile, which has already been shown to be useful in comparing arthritis with other diseases and treatments, can also be scored specifically to make it more useful in studies of osteoarthritis and rheumatoid arthritis.

Algorithms↗