PubMed Health⌕ Search

Biomedical subjects

David Feeny

Publications and source records attributed to David Feeny.

At least 19 recordsLinked to original sources

Effects of nocturnal noninvasive mechanical ventilation on heart rate variability of patients with advanced COPD.

BACKGROUND: Cardiovascular comorbidities have a negative impact on the health status and prognosis of patients with COPD. We determined whether nocturnal noninvasive (positive) mechanical ventilation (NIMV) can improve heart rate variability (HRV), decrease circulating natriuretic peptide levels, and improve functional performance of patients with very advanced COPD. METHODS: A randomized, double-blind, parallel controlled trial was conducted in 23 participants with stable but advanced COPD. Participants received standard medical therapy plus nocturnal NIMV or standard medical therapy plus sham NIMV for 3 months. RESULTS: After 3 months of NIMV therapy, the 24-h triangular interpolation of N-N intervals increased from 322 to 473 ms (p = 0.034), the 24-h HRV index (HRVI) increased from 21.8 to 29.9 ms (p = 0.035), nocturnal HRVI increased from 6.1 to 8.0 ms (p = 0.026), and the SD of the average N-N interval increased from 37 to 41 ms (p = 0.020). None of these indexes changed significantly in the control group. Additionally, compared with the control group, the pro-atrial natriuretic peptide levels declined significantly in the NIMV group (p = 0.013). CONCLUSIONS: NIMV applied nocturnally over 3 months may improve HRV, reduce circulating natriuretic peptide levels, and enhance the functional performance of patients with advanced but stable COPD. While not definitive due to small sample size, these data suggest that nocturnal NIMV may reduce the impact of cardiac comorbidities in COPD patients.

Aged↗

Health status measurements at diagnosis as predictors of survival among adults with brain tumors.

PURPOSE: The intent of this study was to determine whether baseline measures of functional capacity and performance could be used to predict survival in adults following the diagnosis of brain tumors. PATIENTS AND METHODS: Comprehensive health status and health-related quality of life (HRQL) were measured using the Health Utilities Index (HUI; McMaster University, Hamilton, Canada) system by a self-assessment questionnaire in a survey of 100 consecutive patients. The Karnofsky Performance Score (KPS) and Folstein's Mini-Mental State Examination (MMSE) scores were measured by a physician blinded to the HUI results. The patients were observed for up to 5 years to recorded dates of death. RESULTS: An HUI questionnaire was completed for 93% of the patients and 69% died within 5 years of assessment. The HUI revealed a burden of morbidity and complexity of disability that far exceeded that reported for the general population. KPS and MMSE correlated strongly with each other (r = 0.52; P < .001). A decrease of 0.1 units in HUI Mark 2 (HUI2) self-care single-attribute utility score was associated with an increased hazard of death of 30% (P = .023) for patients with low-grade tumors (n=25). For patients with high-grade tumors (n=56), a 10 unit decrease in the KPS, a 5 unit decrease in MMSE, and a 0.1 decrease in HUI Mark 3 (HUI3) speech and dexterity single-attribute scores were associated with an increased hazard of death of 20% (P = .022), 26% (P = .015), 36% (P = .021), and 18% (P = .035), respectively. CONCLUSION: Scores derived from the measurement of HRQL following diagnosis can predict survival in adults with brain tumors.

Adult↗

Stress reactions and perceived difficulties of lay responders to a medical emergency.

BACKGROUND: Bystander CPR rates remain low. One reason may be that the thought of responding to an emergency is so stressful that it decreases the willingness of laypersons to respond. PURPOSE: The purpose of this study was to quantify the amount of stress experienced by lay responders to a medical emergency and to identify barriers that may have impeded their response to the event. METHODS: Responses from 1243 laypersons responding to an emergency during the Public Access Defibrillation Trial were analyzed in a mixed methods study. Stress related to the event was recorded using a 0 (none) to 5 (severe) scale. Qualitative responses to the question of "What was most difficult?" about the event were analyzed using content analysis. RESULTS: Reported stress levels were low overall (mean 1.2, median 1.0). Laypersons responding to an emergency presumed to be a cardiac arrest had higher stress than those involved in other events (median 2.0 versus 1.0). Stress levels were higher in residential than in public settings (mean 1.41, median 1.0 versus mean 1.13, median 1.0). Those who fit a certain profile (females, non-native English speakers) reported statistically higher stress levels than others. A total of 614 qualitative responses were studied and aggregated into four major categories of difficulty: practical issues; characteristics of the victim; interpersonal issues; thoughts and feelings of the lay responder. Most difficulties were in the category of practical issues. CONCLUSIONS: Among these study volunteer lay responders, low levels of stress were reported. Incorporating descriptions of the difficulties experienced by lay responders in CPR/AED training curricula may make courses more realistic and useful.

Adult↗

Analyzing oncology clinical trial data using the Q-TWiST method: clinical importance and sources for health state preference data.

PURPOSE: The Quality-adjusted Time Without Symptoms of disease and Toxicity (Q-TWiST) analysis method is frequently applied to evaluating outcomes in cancer clinical trials, but there is little information on what constitutes a clinically important difference (CID). We reviewed the Q-TWiST, health-related quality of life (HRQL) and utility measurement literature to develop recommendations for CID for the Q-TWiST. We also provide recommendations for measuring health utilities and for the design of Q-TWiST studies. METHODS: The English language literature was searched between 1986 and 2003 for Q-TWiST studies in oncology. We estimated the percent differences between treatments based on median follow-up duration for overall, progression-free and quality-adjusted survival. We also reviewed the relevant HRQL and utility literature on clinical importance. RESULTS: The overall differences between treatments for most (56%) of the observed, published values for Q-TWiST analyses ranged between 12% and 19%. Three-fourths of the Q-TWiST studies had gains in survival of 12%-17%, while differences in progression-free survival ranged from 12% to 26%. Studies that have evaluated the clinical importance of changes in HRQL scores suggest that changes of 5%-10% are clinically meaningful, and other research suggests that 0.5 standard deviation is a reasonable threshold for changes in HRQL for chronic diseases. Similarly, one guideline from the health state utility literature is that a 5%-10% difference in standard gamble utility scores is clinically important. Various sources are available for health utilities for Q-TWiST studies and the most valid are derived from patients or the general public, although most studies rely on sensitivity analyses with no collection of utilities. CONCLUSIONS: We recommend that the CID for Q-TWiST is 10% of overall survival in a study, and differences of 15% are clearly clinically important. If less is known about a specific treatment and/or disease area, the CID should be greater than 5% but not more than 10% in planning sample size and statistical power. These CID estimates should be interpreted with caution, pending confirmation in future studies by direct patient assessment of the clinically relevant health states for Q-TWiST.

Clinical Trials as Topic↗

A study of the construct validity of the Health Utilities Index Mark 3 (HUI3) in patients with schizophrenia.

This study assessed the construct validity of the Health Utilities Index Mark 3 (HUI3) in patients with schizophrenia. Patients with schizophrenia recruited from a tertiary mental hospital in Singapore completed the HUI3, the Short-Form 36 Health Survey (SF-36) and the Schizophrenia Quality of Life Scale (SQLS). Patients were assessed for presence and absence of 22 common psychiatric symptoms. Construct validity was assessed using 6 a priori hypotheses. Two hundred and two patients (mean age: 37.8 years, female: 52%) completed the survey. As hypothesized, overall HUI3 utility scores were correlated with SF-36 measures (Spearman's rho: 0.19 to 0.51), SQLS scales (Spearman's rho: -0.56 to -0.36), and the number of psychiatric symptoms (Spearman's rho: -0.49). The HUI3 emotion attribute was moderately correlated with SF-36 mental health (Spearman's rho: 0.45) and SQLS psychosocial scales (Spearman's rho: -0.43), and HUI3 pain attribute was strongly correlated with SF-36 bodily pain scale (Spearman's rho: 0.58). The mean HUI3 overall, emotion, cognition, and speech scores for patients with schizophrenia were 0.07, 0.09, 0.04 and 0.04 points lower than respective age-, sex- and ethnicity-adjusted population norms (p<0.001 for all, ANCOVA). This study provides evidence for the construct validity of the HUI3 in patients with schizophrenia.

Adult↗

Patient-focused measures of functional health status and health-related quality of life in pediatric orthopedics: a case study in measurement selection.

The objectives of this report are to review the assessment of patient-focused outcomes in pediatric orthopedic surgery, to describe a framework for identifying appropriate sets of measures, and to illustrate an application of the framework to a challenging orthopedic problem.A detailed framework of study design and measurement factors is described. The factors are important for selecting appropriate instruments to measure health status and health-related quality of life (HRQL) in a particular context. A study to evaluate treatment alternatives for patients with neurofibromatosis type 1 and congenital tibial dysplasia (NF1-CTD) provides a rich illustration of the application of the framework. The application involves great variability in the instrument selection factors. Furthermore, these patients and their supportive caregivers face numerous complex health challenges with long-term implications for HRQL. Detailed summaries of important generic preference-based multi-attribute measurement systems, pediatric health profile instruments, and pediatric orthopedic-specific instruments are presented. Age-appropriate generic and specific measures are identified for study of NF1-CTD patients. Selected measures include the Activities Scale for Children, Gillette Functional Assessment Questionnaire Walking Scale, Health Utilities Index, and Pediatric Inventory of Quality of Life. Reliable and valid measures for application to pediatric orthopedics are available. There are important differences among measures. The selected measures complement each other. The framework in this report provides a guide for selecting appropriate measures. Application of appropriate sets of measures will enhance the ability to describe the morbidity of pediatric orthopedic patients and to assess the effectiveness of alternative clinical interventions. The framework for measurement of health status and HRQL from a patient perspective has relevance to many other areas of orthopedic practice.

Activities of Daily Living↗

Methodological design for economic evaluation in Public Access Defibrillation (PAD) trial.

OBJECTIVE: Our objective is to describe the rationale and methods for the economic analysis of the PAD trial. The objective of this analysis is to assess whether automated external defibrillators (AEDs) use by lay responders is good value for money. METHODS: Design. This economic evaluation is being conducted concurrently with a randomized trial of (a) control--training to recognize arrest, access 911, and administer cardiopulmonary resuscitation (CPR) while awaiting arrival of emergency medical services providers versus (b) intervention--training to recognize arrest, access 911, administer CPR, and use an AED while awaiting emergency medical services providers. Lay responders in either group were trained to deliver the study intervention. Population. Participating sites identified distinct units with a population of at least 250 people aged > or = 50 years. Outcome. The primary economic outcome is the incremental cost-effectiveness ratio of intervention versus control. RESULTS: Nine hundred ninety-three units including 1260 public and residential locations were randomized. There were 30 survivors in the intervention group and 15 in the control group (P = .03). Sampling will identify program and health care costs. A societal perspective will be adopted. Incremental cost effectiveness will be estimated by using bootstrapping and decision analytic modeling. CONCLUSION: The study will demonstrate whether defibrillation by lay responders improves outcomes at reasonable cost. If so, then the thousands of lives will be improved annually. If not, then limited resources can be invested in other interventions. Our methods also provide a framework for economic evaluations of other interventions for acute cardiovascular events.

Adult↗

A cohort study found the RAND-12 and Health Utilities Index Mark 3 demonstrated construct validity in high-risk primary care patients.

OBJECTIVE: The Short Form 12 (SF-12) is widely used in primary care settings. The RAND-12 Health Status Inventory (HSI) and the Health Utilities Index Mark 3 (HUI3) have not been as widely used in such settings. The objective of this study was to examine the construct validity of the RAND-12 and HUI3 in the context of high-risk primary care patients. STUDY DESIGN AND SETTING: The SF-12, HUI2, and HUI3 were administered to a cohort of high-risk primary care patients. RAND-12 summary scores for physical and mental health were generated. Single-attribute utility scores for each dimension of health status and overall health in HUI3 were computed. A priori hypotheses were specified. RESULTS: In general, the relationships among RAND-12 and HUI3 scores were consistent with construct validity. Twelve of 24 a priori predictions were confirmed. However, predictions about the correlations between the number of medical conditions and the number of medications and the measures of health-related quality of life were, in general, not confirmed. CONCLUSIONS: The RAND-12 and HUI3 seem to be useful among primary care patients with diverse chronic conditions. Further investigation is warranted.

Cohort Studies↗

Test-retest reliability of health utilities index scores: evidence from hip fracture.

OBJECTIVES: There is relatively little evidence on the test-retest reliability of utility scores derived from multiattribute measures. The objective was to estimate test-retest reliability for Health Utilities Index Mark 2 (HUI2) and Mark 3 (HUI3) utility scores in patients recovering from hip fracture. METHODS: We enrolled an inception cohort of hip fracture patients within 3 to 5 days of surgery. Baseline assessments included the Functional Independence Measure (FIM), Folstein Mini-Mental State Examinations, and the HUI2 and HUI3 questionnaire. Follow-up assessments at 1, 3, and 6 months also included a global change question. Test-retest reliability was assessed as agreement between 3- and 6-month scores using the intraclass correlation coefficient (ICC). Two approaches were used to classify patients as stable; a third approach based on the generalizability theory was also used. Patients were classified as stable if their FIM overall scores changed by 10 points or fewer and if they classified themselves as having experienced no or only a little change according to their global change question. RESULTS: Complete data at both the 3- and 6-month assessments based on self-report were available for 196 patients; 141 patients with complete data were classified as stable. The ICCs for HUI2 and HUI3 for stable patients were 0.71 and 0.72; the ICCs derived from the generalizability theory were 0.76 and 0.77. CONCLUSIONS: Test-retest reliability for HUI in this cohort was similar to reliability estimates for other preference-based multiattribute and generic health-profile measures--in the acceptable range for making valid group-level comparisons.

Aged↗

A test of prospect theory.

OBJECTIVES: Prospect theory (PT) hypothesizes that people judge states relative to a reference point, usually assumed to be their current health. States better than the reference point are valued on a concave portion of the utility function; worse states are valued on a convex portion. Using prospectively collected utility scores, the objective is to test empirically implications of PT. METHODS: Osteoarthritis (OA) patients undergoing total hip arthroplasty periodically provided standard gamble scores for three OA hypothetical states describing mild, moderate, and severe OA as well as their subjectively defined current state (SDCS). Our hypothesis was that most patients improved between the pre- and postsurgery assessments. According to PT, scores for hypothetical states previously > SDCS but now < SDCS should be lower at the postsurgery assessment. RESULTS: Fourteen patients met the criteria for testing the hypothesis. Predictions were confirmed for 0 patients; there was no change or mixed results for 6 patients (42.9 percent); and scores moved in the direction opposite to that predicted by PT for 8 patients (57.1 percent). CONCLUSIONS: In general, the direction and magnitude of the changes in hypothetical-state scores do not conform to the predictions of PT.

Aged↗

Self-reported health status of the general adult U.S. population as assessed by the EQ-5D and Health Utilities Index.

OBJECTIVE: This study aimed to describe the self-reported health status of the general adult U.S. population using 3 multi-attribute preference-based measures: the EQ-5D, Health Utilities Index Mark 2 (HUI2), and Mark 3 (HUI3). METHODS: We surveyed the general adult U.S. population using a probability sample with oversampling of Hispanics and non-Hispanic blacks. Respondents to this home-visit survey self-completed the EQ-5D and HUI2/3 questionnaires. Overall health index scores of the target population and selected subgroups were estimated and construct validity of these measures was assessed by testing a priori hypotheses. RESULTS: Completed questionnaires were collected from 4048 respondents (response rate: 59.4%). The majority of the respondents were women (52.0%); the mean age of the sample was 45 years, with 14.8% being 65 or older. Index scores (standard errors) for the general adult U.S. population as assessed by the EQ-5D, HUI2, and HUI3 were 0.87 (0.01), 0.86 (0.01), and 0.81 (0.01), respectively. Generally, younger, male and Hispanic or non-Hispanic black adults had higher (better) index scores than older, female and other racial/ethnic adults; index scores were higher with higher educational attainment and household income. The 3 overall preference indices were strongly correlated (Pearson's r: 0.67-0.87), but systematically different, with intraclass correlation coefficients between these indices ranging from 0.59 to 0.77. CONCLUSIONS: This study provides U.S. population norms for self-reported health status on the EQ-5D, HUI2, and HUI3. Although these measures appeared to be valid and demonstrated similarities, health status assessed by these measures is not exactly the same.

Adolescent↗

Comparing short form 6D, standard gamble, and Health Utilities Index Mark 2 and Mark 3 utility scores: results from total hip arthroplasty patients.

OBJECTIVES: The objectives are to compare SF-6D, standard gamble (SG), and Health Utilities Index (HUI) utility scores, compare change scores, and compare responsiveness. METHODS: A cohort of osteoarthritis patients referred for total hip arthroplasty (THA) were evaluated at the time of referral and followed until 3 months after THA. Patients were assessed using the SF-36, HUI2, HUI3, and the SG. Agreement is assessed using the intra-class correlation (ICC). Responsiveness is assessed using effect size, standardized response mean, and paired t-test. RESULTS: Data was available for 86 patients at baseline and for 63 at both pre- and post-surgery. At baseline mean SF-6D (0.61), SG (0.62), and HUI2 (0.62) scores were similar; the mean HUI3 score (0.52) was lower. Standard deviations were 0.10, 0.32, 0.19, and 0.22. At baseline, agreement between SF-6D and SG scores was 0.13, agreement between SF-6D and HUI2 was 0.47, and agreement between SF-6D and HUI3 was 0.28. Agreement at pre- and post-surgery was similar. The change in scores between post- and pre-surgery was 0.10 for SF-6D, 0.16 for SG, 0.22 for HUI2, and 0.23 for HUI3. Effect sizes were 1.10 for HUI2, 1.08 for HUI3, 1.06 for SF-6D, and 0.48 for the SG. CONCLUSIONS: Agreement between SG scores and SF-6D and HUI scores was low. The estimate of change in utility associated with THA was lowest for SF-6D. Additional longitudinal studies to compare utility measures appear to be warranted.

Aged↗

Economic evaluation of treatments for cancer in childhood.

Treatment of cancer in childhood is an expensive undertaking for the health-care system and for the affected families. As there is a substantial burden of treatment-related morbidity, it is important to determine whether the effects of treatment are worth these monetary costs, especially from a societal perspective. Economic evaluation affords a comparison of the costs and consequences (effects) of relevant therapeutic alternatives. Preference-based measures of health-related quality of life are particularly useful for assessing the effects of treatment, for these tools integrate mortality and morbidity. These measures provide utility scores that can be used as weights on survival data to compute quality-adjusted life years (QALYs). Costs are incurred both within and outside of the health-care system. The former should include those in front-line patient care departments (e.g. nursing); the pro-rated share of the expenses of service departments (e.g. materials management) to those in the front line; and the fully allocated costs for capital invested in lands, building and equipment. The latter are costs borne by families that are both out-of-pocket (e.g. for over-the-counter drugs) as well as related to time spent in providing care, which may involve foregone income. Costs and consequences should be subject to discounting; a process for converting those items incurred in the future into contemporary equivalents. Economic evaluation provides estimates of incremental discounted costs per discounted QALY gained. By almost any interpretative standard this appears attractive with respect to cancer in childhood. Examples are provided with the encouragement that economic evaluation be undertaken in more clinical trials in paediatric oncology.

Child↗

Comparing directly measured standard gamble scores to HUI2 and HUI3 utility scores: group- and individual-level comparisons.

Directly measured standard gamble (SG) utility scores reflect the respondent's assessment and valuation of their own health status. Scores from the health utilities index (HUI) are based on self-assessed health status but valued using community preferences obtained using the SG. Our objectives were to find if mean directly measured utility scores agree with mean HUI mark 2 (HUI2) and mean HUI mark 3 (HUI3) scores. Also, if individual directly measured utility scores agree with HUI2 and HUI3 scores, and whether HUI2 and HUI3 scores agree. Questionnaires based on the HUI2 and HUI3 health-status classification systems were administered by interviewers to 140 teenage survivors of extremely low birthweight (ELBW) and 124 control group teens. Respondents were asked to think about their own usual health states using six dimensions from HUI2 and value that state using the SG. Mean SG scores are compared with mean HUI2 and mean HUI3 scores using paired sample t-tests. Mean HUI2 scores are compared with mean HUI3 scores. Agreement among scores is assessed using intra-class correlation coefficient (ICC). The effect of severity of health-state morbidity on agreement was assessed using three approaches. ELBW cohort mean (standard deviation) SG, HUI2, and HUI3 scores were 0.90 (0.20), 0.89 (0.14), and 0.80 (0.22). Results for controls were 0.93 (0.11), 0.95 (0.09), and 0.89 (0.13). Mean SG and HUI2 scores did not differ; mean SG and HUI3 did differ; mean HUI2 and HUI3 also differed. At the individual level for ELBW, the ICCs between SG and HUI2, SG and HUI3, and HUI2 and HUI3 scores were 0.13, 0.28, and 0.64. For controls the ICCs were 0.14, 0.24, and 0.56. HUI2 scores appear to match directly measured utility scores reasonably well at the group level. HUI2 and HUI3 scores differ systematically. At the individual level, however, HUI2 and HUI3 scores are poor substitutes for directly measured scores.

Adolescent↗

Comparing short form and RAND physical and mental health summary scores: results from total hip arthroplasty and high-risk primary-care patients.

OBJECTIVES: Summary physical health scores for the Short Form (SF) measures are computing using positive weights for physical items and negative weights for mental health items. Mental health summary scores use positive weights for mental items and negative weights for physical. The RAND Health Status Inventory (HSI) measures do not use negative weights. Do these different approaches to scoring matter? The objective was to compare summary scores using both the SF and RAND-HSI. METHODS: SF-36 and the Health Utilities Index Mark 3 (HUI3) were administered to a cohort of patients waiting for elective total hip arthroplasty (THA). SF-12 and HUI3 were administered to a cohort of high-risk primary-care patients. Summary scores were generated and compared. Single-attribute utility scores for emotion in HUI3 were also computed. Canadian and US norms for SF, RAND-HSI, and HUI3 were used to interpret results. RESULTS: For THA patients, mean physical health scores were 28 and 36 for SF and RAND-HSI. Mean mental health scores were 55 and 42. For the primary-care patients, the scores were 34 and 36 for physical and 46 and 40 for mental health. CONCLUSIONS: SF and RAND-HSI provided somewhat similar summary scores in the THA study. However, SF and RAND-HSI mental health scores differed in the primary-care patient cohort and results from HUI3 corroborate the mental health deficits identified by the RAND-HSI. It may be wise for investigators to use both SF and RAND-HSI scoring systems.

Arthroplasty, Replacement, Hip↗

Is the Health Utilities Index valid in total hip arthroplasty patients?

PURPOSE: The purpose of the study was to examine the construct validity of the Health Utilities Index Mark 2 (HU12) and Mark 3 (HU13) in patients with osteoarthritis (OA) needing total hip arthroplasty (THA). BACKGROUND: One hundred and fourteen OA patients (mean age = 69.2; SD = 8.9) who were waiting to see a surgeon for an evaluation for THA completed baseline measures that included the HU12, HU13, SF-36, Harris Hip Scale, WOMAC, MACTAR, State-Trait Anxiety Inventory, and the 6-min walk test. METHODS: We examined 87 a priori hypotheses by correlating (one-tailed zero-order correlations) the single-attribute utility scores for the pain, emotion, mobility, ambulation, self-care, dexterity, vision, hearing, and speech attributes of the HU12 and HU13 and the overall HU12 and HU13 utility scores to specified subscales of the other measures. RESULTS: The zero-order correlations confirmed 75% of our a priori hypotheses suggesting that the constructs within the HU12 and HU13 were, in general, related to similar constructs in other measures as expected. CONCLUSIONS: The evidence suggests that HU12 and HU13 are valid for use in OA and THA studies.

Aged↗

Enhancing primary care for complex patients. Demonstration project using multidisciplinary teams.

PROBLEM BEING ADDRESSED: Communication between community-based providers is often sporadic and problem-focused. OBJECTIVE OF PROGRAM: To implement collaborative community-based care among providers distant from one another and to improve or maintain the health of high-risk community-dwelling patients, with a focus on medication use. PROGRAM DESCRIPTION: Six primary health care teams were formed of a family physician, a pharmacist, and a home care case manager (nurse). Three of these teams also had a family physician's office nurse. Teams received training and decided on processes of care that included a home visit, medication history, and weekly 1.5-hour face-to-face team meetings. In 151 team conferences, 705 medication or health issues were identified for 182 patients over 6 months. Medication adherence was improved at 3 and 6 months. After 6 months, all providers had a greater understanding of the roles of the other providers. CONCLUSION: Primary health care teams developed in this study require few structural changes to existing health care systems, but will require more reimbursement options.

Aged↗