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Nancy Kline Leidy

Publications and source records attributed to Nancy Kline Leidy.

11 recordsLinked to original sources
PubMed2006

Evolving concepts in the measurement of treatment effects.

This is an interesting time in the evolution of clinical research, as the convergence of scientific, social, and technological advances influences the development of new measurement strategies and creates new challenges and opportunities in the evaluation of treatment outcomes. The purpose of this paper is to provide a brief overview of the forces of change influencing clinical research in general and measurement, specifically, discuss current challenges in the evaluation of treatment outcomes in chronic obstructive pulmonary disease and propose several areas for further research. Five key challenges are discussed: accuracy in the selection and measurement of endpoints; appropriate timing and recall; measurement efficiencies using aggregation techniques or item response theory; interpretation, including the debate concerning the minimal important difference; and the need for "real world" studies with real-world measures to understand treatment effectiveness. Each of these areas offers interesting challenges and opportunities for further development and research.

Biomedical Research↗
PubMed2005

Bridging the gap: using triangulation methodology to estimate minimal clinically important differences (MCIDs).

This paper proposes the use of triangulation methodology to derive guidelines for interpreting change scores on health outcome measures. Triangulation integrates results from global ratings with clinical benchmarks of change, statistical estimates of magnitude, and qualitative data from patients and/or clinicians to derive guidelines that are not field-specific or method bound. A case study is presented to illustrate how this methodology can be applied. Secondary analyses were performed on blinded data from 2,971 patients enrolled in three phase IlIa clinical trials to develop guidelines for interpreting change scores on the Breathlessness Diary (BD), a relatively new approach for evaluating dyspnea outcomes in patients with chronic obstructive pulmonary disease. BD scores were examined by disease severity and rescue medication use. In addition, mean BD change scores by physician global ratings of efficacy were juxtaposed with changes in forced expiratory volume (FEV1) and St. George's Respiratory Questionnaire scores. Percent change, effect size, one-half standard deviation, and the standard error of measurement were used as statistical indicators of magnitude. Data from qualitative interviews provided insight into patient perspectives of change in dyspnea. Taking into consideration results across estimation methods, guidelines were developed for defining large, moderate, and small group-level mean changes on the BD. Areas of divergence and convergence across statistical indicators and clinical benchmarks in this case study highlight the importance of using triangulation methodology to derive guidelines that are both empirically sound and clinically relevant.

Adult↗
PubMed2005

The impact of severe respiratory syncytial virus on the child, caregiver, and family during hospitalization and recovery.

OBJECTIVE: To quantify the magnitude of child, caregiver, and family distress associated with hospitalization for severe respiratory syncytial virus (RSV) and the posthospitalization recovery period. DESIGN: A prospective study of 46 RSV-hospitalized infants and children < or =30 months of age with a history of prematurity (gestational age of < or =35 weeks) and 45 age-matched control subjects was performed. RSV group data were gathered during hospitalization and on days 4, 14, 21, and 60 after discharge; control group data were collected at the end of the RSV season and 60 days thereafter. MAIN OUTCOME MEASURES: RSV severity; caregiver's rating of the child's health (100-point rating) and functional status (Functional Status IIR); caregiver health, stress (7-point rating), and anxiety (Spielberger State Anxiety Inventory); and family health and functioning (Family Adaptability and Cohesion Evaluation Scale II) were recorded. RESULTS: The mean age of the sample was 10.2 months; 51% of the subjects were male. The average duration of hospital stay for the RSV group was 5.8 +/- 8 days. Most patients received supplemental oxygen (76%) and were monitored for apnea (60%). The mean age of the caregivers (93% mothers) was 29 years. During hospitalization, the RSV-infected patients' health and functional status were significantly poorer than those of control subjects. Caregivers of RSV-infected children reported more stress, greater anxiety, poorer health, and poorer family health and functioning. As long as 60 days after discharge, caregivers of RSV-infected children reported the children's health as significantly poorer and were personally more anxious, compared with control subjects. CONCLUSIONS: RSV-related hospitalization creates significant distress for infants and children, caregivers, and families, with some effects extending as long as 60 days after discharge.

Adult↗
PubMed2003

Reduction in oral corticosteroid use with mometasone furoate dry powder inhaler improves health-related quality of life in patients with severe persistent asthma.

Severe persistent asthma can have a substantial impact on a patient's health-related quality of life (HRQL), both as a result of symptoms and from side effects of treatment. The HRQL impact of two doses (400 and 800 microg twice daily) of mometasone furoate dry powder inhaler (MF DPI) was compared with placebo in patients with severe persistent asthma previously maintained on oral steroids as a component of a previously published randomized, 12-week, double-blind, placebo-controlled, multicenter trial. A 9-month open-label extension (OLE), with all patients treated with MF DPI, followed. Patients 12 years of age or older completed a generic HRQL measure, the Medical Outcomes Trust Short Form-36 (SF-36), and an asthma-specific measure, the Marks Asthma Quality of Life Questionnaire (AQLQ-M), at baseline, at endpoint (last evaluable visit) of the double-blind phase (EODBP), and after the first 3 months of the OLE. Of 132 patients enrolled in the study, 128 provided HRQL data at baseline and at EODBP. Mean SF-36 scores at baseline showed significant HRQL impairment compared with U.S. general population norms. With treatment, the reduction in oral corticosteroid (OCS) requirements of the MF-DPI-treated groups was accompanied by significant (p < 0.05) improvement over placebo in the physical domain of HRQL (SF-36 physical component summary score and the physical function subscale) at EODBP. MF-DPI-treated patients also showed significant improvements at EODBP in each of the four subscales of the AQLQ-M (p<0.05). From EODBP to the OLE 3-month endpoint, patients treated with MF DPI twice daily maintained, or improved, SF-36 scores in most domains. Symptomatic improvement and reduction in OCS use with MF DPI were accompanied by significant improvement in HRQL in patients with severe persistent asthma. These improvements were maintained during the 3-month period of the OLE in which HRQL was evaluated.

Administration, Inhalation↗
PubMed2003

The breathlessness, cough, and sputum scale: the development of empirically based guidelines for interpretation.

BACKGROUND: A patient report of respiratory symptoms in COPD is essential to successfully monitoring disease, adjusting treatment, and evaluating outcomes. OBJECTIVE: To develop empirically based guidelines for interpreting mean changes in symptom scores using the Breathlessness, Cough, and Sputum Scale (BCSS). METHODS: Analyses were performed on data from three multinational trials (n = 2,971). Mean changes in BCSS score with treatment were examined by physician and patient ratings of treatment efficacy, juxtaposed with percentage change in symptoms, statistical effect size (ES), DeltaFEV(1), and change in St. George Respiratory Questionnaire (SGRQ) score. BCSS scores during an exacerbation were examined relative to changes in peak expiratory flow and rescue medication use. RESULTS: Mean baseline BCSS total score was 5.2 +/- 2 (+/- SD); 90% of scores were between 2 and 9. Highly efficacious treatment (n = 257; physician rating) was associated with a DeltaBCSS total score of - 1.3 +/- 1.8, representing a 24% improvement (ES = 0.7), and corresponding to a 10% improvement in FEV(1) and DeltaSGRQ score total of - 10.3 +/- 13.8. Similar changes in BCSS score were observed during recovery from an exacerbation (n = 713; - 1.3 +/- 1.8). Mean change with moderately efficacious treatment (n = 965) was - 0.7 +/- 1.8, a 13% improvement (ES = 0.3) corresponding to DeltaSGRQ total score of - 6.8 +/- 12.6. Mildly efficacious treatment (n = 891) was associated with a change of - 0.35, a 7% improvement (ES = 0.18), with a DeltaFEV(1) <1% and DeltaSGRQ total score of - 2.6 +/- 11.7. CONCLUSIONS: Patient-reported daily symptom data are sensitive to change and useful for both observational studies and controlled clinical trials of patients with COPD. A mean DeltaBCSS total score > 1.0 represents substantial symptomatic improvement, changes of approximately 0.6 can be interpreted as moderate, and changes of 0.3 can be considered small.

Clinical Trials as Topic↗
PubMedDate not supplied

The New York Heart Association Classes and functional status: what are we really measuring?

The New York Heart Association (NYHA) Classes are used to appraise the status of patients with heart disease and evaluate treatment outcomes in clinical and research settings. Ambiguity exists concerning the construct the Classes represent and the optimal way to capture and interpret the information. This article examines the NYHA Classes within the context of a published functional status framework by Leidy. The framework proposes that (1) physiological indicators provide information on capacity, (2) physical activity characterizes performance, and (3) symptoms accompanying activity offer insight into reserve. It is proposed that the NYHA Classes provide a summary statement of both the reduction in reserve accompanying a decline in capacity and the concomitant increase in capacity utilization required to maintain performance in patients with heart disease. This premise is illustrated quantitatively through secondary analysis of data from 22 patients with ischemic heart disease and left ventricular dysfunction.

Heart Diseases↗
PubMedDate not supplied

Incorporating the patient's perspective into drug development and communication: an ad hoc task force report of the Patient-Reported Outcomes (PRO) Harmonization Group meeting at the Food and Drug Administration, February 16, 2001.

BACKGROUND: The extent to which patient-based outcomes can be used to evaluate and communicate the effect of new drugs and devices is a subject of much debate. Criteria for evaluating the scientific quality of data to support health-related quality of life (HRQL) and other patient-based labeling and promotional claims in the United States and Europe have been proposed by various scientists and organizations. Since March 2000, a working group composed of members of the International Society for Quality of Life Research (ISOQOL), the International Society for Pharmacoeconomics and Outcomes Research (ISPOR), the Pharmaceutical Manufacturer's Association Health Outcomes Committee (PhRMA-HOC), and the European Regulatory Issues on Quality of Life Assessment (ERIQA) met to discuss and coordinate the various recommendations by their respective groups and address the need to harmonize outcomes review criteria within and across United States and European regulatory agencies. Over time, the discussion expanded from HRQL outcomes to include any outcome based on data provided by the patient or patient proxy, that is, patient-reported outcomes (PROs). The working group therefore became known as the PRO Harmonization Group. METHODS: Working with a member of the US Food and Drug Administration (FDA), four key issues requiring clarification were identified: how PROs are defined and put into operation for research purposes; the added value of PROs in the drug review and evaluation process; selected questions related to the PRO measurement and research methodology; and the interest and demand for PRO information by decision makers. On February 15, 2001, all members of the PRO Harmonization Group attended a meeting in Rockville, Maryland, to discuss these four issues further, and on February 16, 2001, a formal presentation was made to representatives from various departments and reviewing divisions of the FDA. These presentations are summarized in this report. RESULTS: All participants agreed that PROs are important for understanding the impact of treatment on patient functioning and well-being. They also stressed the need to communicate PRO information to key decision makers, including regulatory agencies, clinicians, patients and their families, and payers. Finally, the meeting resulted in plans for continuing the dialogue on PRO measurement and interpretation. SUMMARY: The February 16, 2001, meeting represented an important step in harmonizing efforts across various organizations and in opening a dialogue with the FDA around major issues related to methodologic standards for measuring and interpreting PROs in the drug evaluation process.

Advisory Committees↗
PubMedDate not supplied

Assessment of health-related quality of life in children: a review of conceptual, methodological, and regulatory issues.

Recently, the FDA has encouraged testing of medications among pediatric patients during drug development. Pharmaceutical companies have responded by conducting more clinical trials among children, and researchers are becoming aware of the unique challenges of assessing pediatric health outcomes, including health-related quality of life (HRQL). Like adults, children experience effects of illness and treatment beyond physiologic outcomes. Further pediatric HRQL research is necessary to examine these broader psychosocial outcomes and provide a thorough understanding of the effects of treatment on children's health status. The purpose of the current review is to discuss key regulatory and methodologic developments and provide guidance for future research on pediatric HRQL. This review of pediatric HRQL assessment includes five sections: 1). recent pediatric regulatory developments in the United States; 2). issues in defining and conceptualizing pediatric HRQL, including the importance of contextual variables such as family and peer systems; 3). methodologic issues (e.g., the proxy question, developmental differences, response sets) with recommendations for addressing these issues in clinical trials; 4). validated generic and condition-specific pediatric HRQL measures; and 5). a recommendation for additional research on the HRQL impact of childhood psychiatric disorders. It is advocated that assessment of HRQL among children should be conducted regularly as an integral part of drug development.

Adolescent↗
PubMedDate not supplied

Integrating the patient's perspective into device evaluation trials.

Innovations in medical device technology have greatly expanded the range of therapeutic options available to physicians and their patients. The understanding of treatment effects from the patient's perspective is an essential component of a comprehensive assessment of any new therapy, including medical devices. The term "patient-reported outcomes" (PROs) has been growing in use to refer to a cluster of variables such as health-related quality of life, symptoms, physical functioning, psychological well-being, treatment satisfaction, and treatment preferences. As in drug trials, the use of PROs in device evaluation has several methodological challenges, ranging from general concerns about interpretation, to more specific issues related to study design and regulatory approval (use of PROs as primary end points, incorporation in labeling, and product promotion). Successful approaches for integrating PROs into device evaluation trials include the careful selection of appropriate, interpretable PRO end points, accounting for possible confounding factors, and the use of alternatives to placebo-controlled trial designs, such as single-arm pre-post, observational, and registry studies, when the use of placebo control groups is not feasible. This article discusses the potential value and difficulties in measuring PROs in device studies.

Clinical Trials as Topic↗
PubMedDate not supplied

The health-related quality of life effects of once-daily cetirizine HCl syrup in children with seasonal allergic rhinitis.

Seasonal allergic rhinitis (SAR) can adversely impact children's physical, psychological, and social functioning and well-being, that is, their health-related quality of life (HRQL). This study assessed HRQL in children 6 to 11 years treated with cetirizine HCl syrup, while concurrently assessing symptomatic relief and safety. In an open-label, non-comparative study, 544 children from 124 centers in the United States were instructed to take cetirizine HCl syrup (10 cc of 1 mg/mL) each evening for 4 weeks. Children experienced statistically significant improvements in HRQL with significant reductions in mean symptom score (p < 0.001) during the treatment period. Results were consistent across age groups (6-7, 8-9, 10-11 years). These results suggest that the symptomatic relief and tolerability profile of cetirizine HC1 syrup daily translates into improvements in the HRQL of children with SAR. This 4-week open label study is among the first to evaluate the effect of antihistamine treatment on HRQL outcomes in children.

Administration, Oral↗