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Deyo RA, Dworkin SF, Amtmann D, Andersson G, Borenstein D, Carragee E, Carrino J, Chou R, Cook K, DeLitto A, Goertz C, Khalsa P, Loeser J, Mackey S, Panagis J, Rainville J, Tosteson T, Turk D, Von Korff M, Weiner DK. Report of the NIH Task Force on research standards for chronic low back pain. THE JOURNAL OF PAIN 2014; 15:569-85. [PMID: 24787228 PMCID: PMC4128347 DOI: 10.1016/j.jpain.2014.03.005] [Citation(s) in RCA: 320] [Impact Index Per Article: 29.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Revised: 02/24/2014] [Accepted: 03/12/2014] [Indexed: 12/18/2022]
Abstract
UNLABELLED Despite rapidly increasing intervention, functional disability due to chronic low back pain (cLBP) has increased in recent decades. We often cannot identify mechanisms to explain the major negative impact cLBP has on patients' lives. Such cLBP is often termed non-specific and may be due to multiple biologic and behavioral etiologies. Researchers use varied inclusion criteria, definitions, baseline assessments, and outcome measures, which impede comparisons and consensus. Therefore, NIH Pain Consortium charged a Research Task Force (RTF) to draft standards for research on cLBP. The resulting multidisciplinary panel recommended using 2 questions to define cLBP; classifying cLBP by its impact (defined by pain intensity, pain interference, and physical function); use of a minimum dataset to describe research participants (drawing heavily on the PROMIS methodology); reporting "responder analyses" in addition to mean outcome scores; and suggestions for future research and dissemination. The Pain Consortium has approved the recommendations, which investigators should incorporate into NIH grant proposals. The RTF believes that these recommendations will advance the field, help to resolve controversies, and facilitate future research addressing the genomic, neurologic, and other mechanistic substrates of chronic low back pain. We expect that the RTF recommendations will become a dynamic document and undergo continual improvement. PERSPECTIVE A task force was convened by the NIH Pain Consortium with the goal of developing research standards for chronic low back pain. The results included recommendations for definitions, a minimum dataset, reporting outcomes, and future research. Greater consistency in reporting should facilitate comparisons among studies and the development of phenotypes.
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Affiliation(s)
- Richard A Deyo
- Oregon Health and Sciences University, Portland, Oregon.
| | | | | | | | | | | | | | - Roger Chou
- Oregon Health and Sciences University, Portland, Oregon
| | - Karon Cook
- Northwestern University, Evanston, Illinois
| | - Anthony DeLitto
- VA Pittsburgh Healthcare System and University of Pittsburgh, Pittsburgh, Pennsylvania
| | | | - Partap Khalsa
- National Center for Complementary and Alternative Medicine, Bethesda, Maryland
| | - John Loeser
- University of Washington, Seattle, Washington
| | | | - James Panagis
- National Institute for Arthritis, Musculoskeletal and Skin Diseases, Bethesda, Maryland
| | - James Rainville
- New England Baptist Hospital, Roxbury Crossing, Massachusetts
| | | | - Dennis Turk
- University of Washington, Seattle, Washington
| | | | - Debra K Weiner
- VA Pittsburgh Healthcare System and University of Pittsburgh, Pittsburgh, Pennsylvania
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202
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Gossec L, de Wit M, Kiltz U, Braun J, Kalyoncu U, Scrivo R, Maccarone M, Carton L, Otsa K, Sooäär I, Heiberg T, Bertheussen H, Cañete JD, Sánchez Lombarte A, Balanescu A, Dinte A, de Vlam K, Smolen JS, Stamm T, Niedermayer D, Békés G, Veale D, Helliwell P, Parkinson A, Luger T, Kvien TK. A patient-derived and patient-reported outcome measure for assessing psoriatic arthritis: elaboration and preliminary validation of the Psoriatic Arthritis Impact of Disease (PsAID) questionnaire, a 13-country EULAR initiative. Ann Rheum Dis 2014; 73:1012-9. [PMID: 24790067 DOI: 10.1136/annrheumdis-2014-205207] [Citation(s) in RCA: 241] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
INTRODUCTION The objective was to develop a questionnaire that can be used to calculate a score reflecting the impact of psoriatic arthritis (PsA) from the patients' perspective: the PsA Impact of Disease (PsAID) questionnaire. METHODS Twelve patient research partners identified important domains (areas of health); 139 patients prioritised them according to importance. Numeric rating scale (NRS) questions were developed, one for each domain. To combine the domains into a single score, relative weights were determined based on the relative importance given by 474 patients with PsA. An international cross-sectional and longitudinal validation study was performed in 13 countries to examine correlations of the PsAID score with other PsA or generic disease measures. Test-retest reliability and responsiveness (3 months after a treatment change) were examined in two subsets of patients. RESULTS Two PsAID questionnaires were developed with both physical and psychological domains: one for clinical practice (12 domains of health) and one for clinical trials (nine domains). Pain, fatigue and skin problems had the highest relative importance. The PsAID scores correlated well with patient global assessment (N=474, Spearman r=0.82-0.84), reliability was high in stable patients (N=88, intraclass correlation coefficient=0.94-0.95), and sensitivity to change was also acceptable (N=71, standardised response mean=0.90-0.91). CONCLUSIONS A questionnaire to assess the impact of PsA on patients' lives has been developed and validated. Two versions of the questionnaire are available, one for clinical practice (PsAID-12) and one for clinical trials (PsAID-9). The PsAID questionnaires should allow better assessment of the patient's perspective in PsA. Further validation is needed.
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Affiliation(s)
- Laure Gossec
- Department of Rheumatology, UPMC University Paris 06, GRC-UPMC 08 (EEMOIS) and AP-HP, Pitié Salpêtrière Hospital, , Paris, France
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203
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Chen WH, McLeod LD, Nelson LM, Williams VSL, Fehnel SE. Quantitative challenges facing patient-centered outcomes research. Expert Rev Pharmacoecon Outcomes Res 2014; 14:379-86. [PMID: 24758551 DOI: 10.1586/14737167.2014.912133] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Patient-centered outcomes research collects and analyzes data from patients and other stakeholders to improve health care delivery and outcomes and guide health care decisions. However, there are a number of challenges in conducting quantitative analyses of patient-centered data. This article provides an overview of the analytical challenges and describes approaches to consider to overcome the challenges, as well as directions for future development.
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Affiliation(s)
- Wen-Hung Chen
- RTI Health Solutions , 3040 Cornwallis Road, P.O. Box 12194, Research Triangle Park, NC 27709 , USA
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204
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Lacy BE, Lembo AJ, MacDougall JE, Shiff SJ, Kurtz CB, Currie MG, Johnston JM. Responders vs clinical response: a critical analysis of data from linaclotide phase 3 clinical trials in IBS-C. Neurogastroenterol Motil 2014; 26:326-33. [PMID: 24382134 PMCID: PMC4282394 DOI: 10.1111/nmo.12264] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Accepted: 10/29/2013] [Indexed: 12/15/2022]
Abstract
BACKGROUND US Food and Drug Administration (FDA) set a rigorous standard for defining patient responders in irritable bowel syndrome-C (IBS-C; i.e., FDA's Responder Endpoint) for regulatory approval. However, this endpoint's utility for health-care practitioners to assess clinical response has not been determined. We analyzed pooled IBS-C linaclotide trial data to evaluate clinically significant responses in linaclotide-treated patients who did not meet the FDA responder definition. METHODS Percentages of FDA non-responders reporting improvement in abdominal pain, bowel function and/or global relief measures were determined using pooled data from two linaclotide Phase 3 IBS-C trials. KEY RESULTS 1602 IBS-C patients enrolled; 34% of linaclotide-treated and 17% of placebo-treated patients met the FDA Responder Endpoint (p < 0.0001). Among FDA non-responders at week 12, 63% of linaclotide-treated patients reported their abdominal pain was at least somewhat relieved, compared with 48% of placebo-treated patients. For stool frequency, 62% of linaclotide-treated patients reported that they were at least somewhat improved at week 12, compared with 46% of placebo-treated patients. For global IBS symptoms, 65% of linaclotide-treated patients reported at least some IBS-symptom relief, 43% reported adequate relief of IBS symptoms, and 57% reported being satisfied with linaclotide treatment, vs placebo rates of 48%, 34%, and 41% respectively. CONCLUSIONS & INFERENCES Most linaclotide-treated IBS-C patients who were FDA non-responders reported some improvement in abdominal pain and stool frequency, and global relief/satisfaction. In addition to the FDA Responder Endpoint, differing response thresholds and symptom-specific change from baseline should be considered by clinicians for a complete understanding of clinical response to linaclotide and other IBS-C therapies.
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Affiliation(s)
- B E Lacy
- Division of Gastroenterology & Hepatology, Dartmouth-Hitchcock Medical CenterLebanon, NH, USA
| | - A J Lembo
- Division of Gastroenterology, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical SchoolBoston, MA, USA
| | - J E MacDougall
- Research & Development, Ironwood PharmaceuticalsCambridge, MA, USA
| | - S J Shiff
- Clinical Development, Forest Research InstituteJersey City, NJ, USA
| | - C B Kurtz
- Research & Development, Ironwood PharmaceuticalsCambridge, MA, USA
| | - M G Currie
- Research & Development, Ironwood PharmaceuticalsCambridge, MA, USA
| | - J M Johnston
- Research & Development, Ironwood PharmaceuticalsCambridge, MA, USA
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205
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Abstract
The activity of eosinophilic esophagitis (EoE) can be assessed with patient-reported outcomes and biologic measures. Patient-reported outcomes include symptoms and quality of life, whereas biologic measures refer to endoscopic, histologic, and biochemical activity (e.g. blood biomarkers). So far, a validated tool to assess EoE activity in the above-mentioned dimensions is lacking. Given the lack of a standardized way to assess EoE activity in the various dimensions, the results of different clinical trials may be difficult to compare. For symptom assessment in adult patients, the symptom 'dysphagia' should be evaluated according to different standardized food consistencies. Furthermore, symptom assessment should take into account the following items: avoidance of specific food categories, food modification, and time to eat a regular meal. A distinct symptom recall period (e.g. 2 weeks) has to be defined for symptom assessment. Performing an 'esophageal stress test' with ingestion of a standardized meal to measure symptom severity bears the potential risk of acute food bolus impaction and should therefore be avoided. The description of endoscopic findings in EoE has meanwhile been standardized. Histologic evaluation of EoE activity should report either the size of the high-power field used or count the eosinophils per mm(2). There is a current lack of blood biomarkers demonstrating a good correlation with histologic activity in esophageal biopsies. The development and validation of an adult and pediatric EoE activity index is urgently needed not only for clinical trials and observational studies, but also for daily practice.
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Affiliation(s)
- Alain Schoepfer
- Division of Gastroenterology and Hepatology, Centre Hospitalier Universitaire Vaudois/CHUV, Lausanne, Switzerland
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206
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Paulsen A, Roos EM, Pedersen AB, Overgaard S. Minimal clinically important improvement (MCII) and patient-acceptable symptom state (PASS) in total hip arthroplasty (THA) patients 1 year postoperatively. Acta Orthop 2014; 85:39-48. [PMID: 24286564 PMCID: PMC3940990 DOI: 10.3109/17453674.2013.867782] [Citation(s) in RCA: 136] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2013] [Accepted: 09/24/2013] [Indexed: 01/31/2023] Open
Abstract
BACKGROUND AND PURPOSE The increased use of patient-reported outcomes (PROs) in orthopedics requires data on estimated minimal clinically important improvements (MCIIs) and patient-acceptable symptom states (PASSs). We wanted to find cut-points corresponding to minimal clinically important PRO change score and the acceptable postoperative PRO score, by estimating MCII and PASS 1 year after total hip arthroplasty (THA) for the Hip Dysfunction and Osteoarthritis Outcome Score (HOOS) and the EQ-5D. PATIENTS AND METHODS THA patients from 16 different departments received 2 PROs and additional questions preoperatively and 1 year postoperatively. The PROs included were the HOOS subscales pain (HOOS Pain), physical function short form (HOOS-PS), and hip-related quality of life (HOOS QoL), and the EQ-5D. MCII and PASS were estimated using multiple anchor-based approaches. RESULTS Of 1,837 patients available, 1,335 answered the preoperative PROs, and 1,288 of them answered the 1-year follow-up. The MCIIs and PASSs were estimated to be: 24 and 91 (HOOS Pain), 23 and 88 (HOOS-PS), 17 and 83 (HOOS QoL), 0.31 and 0.92 (EQ-5D Index), and 23 and 85 (EQ-VAS), respectively. MCIIs corresponded to a 38-55% improvement from mean baseline PRO score and PASSs corresponded to absolute follow-up scores of 57-91% of the maximum score in THA patients 1 year after surgery. INTERPRETATION This study improves the interpretability of PRO scores. The different estimation approaches presented may serve as a guide for future MCII and PASS estimations in other contexts. The cutoff points may serve as reference values in registry settings.
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Affiliation(s)
- Aksel Paulsen
- Department of Orthopaedic Surgery and Traumatology,Odense University Hospital, Institute of Clinical Research, University of Southern Denmark
| | - Ewa M Roos
- Research Unit for Musculoskeletal Function and Physiotherapy, Department of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense
| | - Alma B Pedersen
- Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus, Denmark.
| | - Søren Overgaard
- Department of Orthopaedic Surgery and Traumatology,Odense University Hospital, Institute of Clinical Research, University of Southern Denmark
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207
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Wang XS, Shi Q, Shah ND, Heijnen CJ, Cohen EN, Reuben JM, Orlowski RZ, Qazilbash MH, Johnson VE, Williams LA, Mendoza TR, Cleeland CS. Inflammatory markers and development of symptom burden in patients with multiple myeloma during autologous stem cell transplantation. Clin Cancer Res 2014; 20:1366-74. [PMID: 24423611 DOI: 10.1158/1078-0432.ccr-13-2442] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
PURPOSE Increasing research suggests that inflammation mediates symptom development. In this longitudinal study, we examined inflammatory factors related to the development of high symptom burden during autologous hematopoietic stem cell transplant (AuSCT) for multiple myeloma. EXPERIMENTAL DESIGN Patients (n = 63) repeatedly reported symptom severity on the MD Anderson Symptom Inventory multiple myeloma module (MDASI-MM) and contributed blood samples periodically for up to 100 days after AuSCT for inflammatory marker assays. The temporal associations between serum inflammatory marker concentrations and symptom severity outcomes were examined by nonlinear mixed-effect modeling. RESULTS Fatigue, pain, disturbed sleep, lack of appetite, and drowsiness were consistently the most severe MDASI-MM symptoms during the study. Peak symptom severity occurred on day 8 after AuSCT, during white blood cell count nadir. Patterns of serum interleukin (IL)-6 (peak on day 9) and soluble IL-6 receptor (sIL-6R; nadir on day 8) expression paralleled symptom development over time (both P < 0.0001). By univariate analysis, serum IL-6, sIL-6R, IL-10, C-reactive protein, macrophage inflammatory protein (MIP)-1α, sIL-1R2, sIL-1RA, and soluble tumor necrosis factor receptor 1 were significantly related to the most severe symptoms during the first 30 days after AuSCT (all P < 0.05). By multivariate analysis, IL-6 (estimate = 0.170; P = 0.004) and MIP-1α (estimate = -0.172; P = 0.006) were temporally associated with the severity of the component symptom score. CONCLUSIONS Systemic inflammatory response was associated with high symptom burden during the acute phase of AuSCT. Additional research is needed to understand how the inflammatory response is mechanistically associated with symptom expression and whether suppression of this response can reduce symptoms without compromising tumor control.
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Affiliation(s)
- Xin Shelley Wang
- Authors' Affiliations: Departments of Symptom Research, Stem Cell Transplantation, Hematopathology, Lymphoma/Myeloma, and Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, Texas
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208
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Schoepfer AM, Safroneeva E, Bussmann C, Kuchen T, Portmann S, Simon HU, Straumann A. Delay in diagnosis of eosinophilic esophagitis increases risk for stricture formation in a time-dependent manner. Gastroenterology 2013; 145:1230-6.e1-2. [PMID: 23954315 DOI: 10.1053/j.gastro.2013.08.015] [Citation(s) in RCA: 543] [Impact Index Per Article: 45.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2013] [Revised: 07/25/2013] [Accepted: 08/07/2013] [Indexed: 12/11/2022]
Abstract
BACKGROUND & AIMS Development of strictures is a major concern for patients with eosinophilic esophagitis (EoE). At diagnosis, EoE can present with an inflammatory phenotype (characterized by whitish exudates, furrows, and edema), a stricturing phenotype (characterized by rings and stenosis), or a combination of these. Little is known about progression of stricture formation; we evaluated stricture development over time in the absence of treatment and investigated risk factors for stricture formation. METHODS We performed a retrospective study using the Swiss EoE Database, collecting data on 200 patients with symptomatic EoE (153 men; mean age at diagnosis, 39 ± 15 years old). Stricture severity was graded based on the degree of difficulty associated with passing of the standard adult endoscope. RESULTS The median delay in diagnosis of EoE was 6 years (interquartile range, 2-12 years). With increasing duration of delay in diagnosis, the prevalence of fibrotic features of EoE, based on endoscopy, increased from 46.5% (diagnostic delay, 0-2 years) to 87.5% (diagnostic delay, >20 years; P = .020). Similarly, the prevalence of esophageal strictures increased with duration of diagnostic delay, from 17.2% (diagnostic delay, 0-2 years) to 70.8% (diagnostic delay, >20 years; P < .001). Diagnostic delay was the only risk factor for strictures at the time of EoE diagnosis (odds ratio = 1.08; 95% confidence interval: 1.040-1.122; P < .001). CONCLUSIONS The prevalence of esophageal strictures correlates with the duration of untreated disease. These findings indicate the need to minimize delay in diagnosis of EoE.
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Affiliation(s)
- Alain M Schoepfer
- Division of Gastroenterology and Hepatology, Centre Hospitalier Universitaire Vaudois / CHUV, Lausanne, Switzerland.
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209
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Joseph SM, Novak E, Arnold SV, Jones PG, Khattak H, Platts AE, Dávila-Román VG, Mann DL, Spertus JA. Comparable performance of the Kansas City Cardiomyopathy Questionnaire in patients with heart failure with preserved and reduced ejection fraction. Circ Heart Fail 2013; 6:1139-46. [PMID: 24130003 DOI: 10.1161/circheartfailure.113.000359] [Citation(s) in RCA: 151] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
BACKGROUND Despite the growing epidemic of heart failure with preserved ejection fraction (HFpEF), no valid measure of patients' health status (symptoms, function, and quality of life) exists. We evaluated the Kansas City Cardiomyopathy Questionnaire (KCCQ), a validated measure of HF with reduced EF, in patients with HFpEF. METHODS AND RESULTS Using a prospective HF registry, we dichotomized patients into HF with reduced EF (EF≤ 40) and HFpEF (EF≥50). The associations between New York Heart Association class, a commonly used criterion standard, and KCCQ Overall Summary and Total Symptom domains were evaluated using Spearman correlations and 2-way ANOVA with differences between patients with HF with reduced EF and HFpEF tested with interaction terms. Predictive validity of the KCCQ Overall Summary scores was assessed with Kaplan-Meier curves for death and all-cause hospitalization. Covariate adjustment was made using Cox proportional hazards models. Internal reliability was assessed with Cronbach's α. Among 849 patients, 200 (24%) had HFpEF. KCCQ summary scores were strongly associated with New York Heart Association class in both patients with HFpEF (r=-0.62; P<0.001) and HF with reduced EF (r=-0.55; P=0.27 for interaction). One-year event-free rates by KCCQ category among patients with HFpEF were 0 to 25=13.8%, 26 to 50=59.1%, 51 to 75=73.8%, and 76 to 100=77.8% (log rank P<0.001), with no significant interaction by EF (P=0.37). The KCCQ domains demonstrated high internal consistency among patients with HFpEF (Cronbach's α=0.96 for overall summary and ≥0.69 in all subdomains). CONCLUSIONS Among patients with HFpEF, the KCCQ seems to be a valid and reliable measure of health status and offers excellent prognostic ability. Future studies should extend and replicate our findings, including the establishment of its responsiveness to clinical change.
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Affiliation(s)
- Susan M Joseph
- Cardiovascular Division, Department of Medicine, Washington University School of Medicine, St Louis, MO
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210
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Yu J, Cheung J. A new health-related quality of life instrument for leukemia: will it be widely adopted soon? Drugs Context 2013; 2013:212253. [PMID: 24432041 PMCID: PMC3884751 DOI: 10.7573/dic.212253] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Accepted: 04/19/2013] [Indexed: 11/21/2022] Open
Affiliation(s)
- Junhua Yu
- Touro University College of Pharmacy, 1310 Club Drive, Mare Island, Vallejo, CA 94592, USA
| | - Joanna Cheung
- Touro University College of Pharmacy, 1310 Club Drive, Mare Island, Vallejo, CA 94592, USA
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211
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Park MJ, Green J, Ishikawa H, Yamazaki Y, Kitagawa A, Ono M, Yasukata F, Kiuchi T. Decay of impact after self-management education for people with chronic illnesses: changes in anxiety and depression over one year. PLoS One 2013; 8:e65316. [PMID: 23785418 PMCID: PMC3681854 DOI: 10.1371/journal.pone.0065316] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2012] [Accepted: 04/28/2013] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND In people with chronic illnesses, self-management education can reduce anxiety and depression. Those benefits, however, decay over time. Efforts have been made to prevent or minimize that "decay of impact", but they have not been based on information about the decay's characteristics, and they have failed. Here we show how the decay's basic characteristics (prevalence, timing, and magnitude) can be quantified. Regarding anxiety and depression, we also report the prevalence, timing, and magnitude of the decay. METHODS Adults with various chronic conditions participated in a self-management educational program (n = 369). Data were collected with the Hospital Anxiety and Depression Scale four times over one year. Using within-person effect sizes, we defined decay of impact as a decline of ≥0.5 standard deviations after improvement by at least the same amount. We also interpret the results using previously-set criteria for non-cases, possible cases, and probable cases. RESULTS Prevalence: On anxiety, decay occurred in 19% of the participants (70/369), and on depression it occurred in 24% (90/369). Timing: In about one third of those with decay, it began 3 months after the baseline measurement (6 weeks after the educational program ended). Magnitude: The median magnitudes of decay on anxiety and on depression were both 4 points, which was about 1 standard deviation. Early in the follow-up year, many participants with decay moved into less severe clinical categories (e.g., becoming non-cases). Later, many of them moved into more severe categories (e.g., becoming probable cases). CONCLUSIONS Decay of impact can be identified and quantified from within-person effect sizes. This decay occurs in about one fifth or more of this program's participants. It can start soon after the program ends, and it is large enough to be clinically important. These findings can be used to plan interventions aimed at preventing or minimizing the decay of impact.
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Affiliation(s)
- M J Park
- Department of Health Communication, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
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212
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Arnold LM, Cappelleri JC, Clair A, Masters ET. Interpreting effect sizes and clinical relevance of pharmacological interventions for fibromyalgia. Pain Ther 2013; 2:65-71. [PMID: 25135038 PMCID: PMC4107878 DOI: 10.1007/s40122-013-0011-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Indexed: 01/14/2023] Open
Abstract
Duloxetine, milnacipran, and pregabalin are approved by the United States Food and Drug Administration for the management of fibromyalgia. A number of meta-analyses, pooled analyses, and systematic reviews have been published in recent years involving the efficacy of these three medications for pain in fibromyalgia. Despite being based on the same clinical data, some analyses found these treatments to have a clinically relevant effect on pain, while others concluded that the advantages were small or of questionable clinical relevance. This commentary discussed possible reasons behind these differing conclusions and explored ways of evaluating the clinical relevance of pharmacological treatments for fibromyalgia. In particular, we considered: (1) the importance of judicious and careful interpretation of average treatment effect size and the recognition that average treatment effect sizes do not always tell the whole story; (2) the utility of individual patient response data to assess clinical relevance; and (3) the importance of considering pain reduction within the context of other benefits due to the presence of associated symptoms in patients with fibromyalgia.
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Affiliation(s)
- Lesley M. Arnold
- Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati College of Medicine, 260 Stetson Street, Suite 3200, Cincinnati, OH 45219 USA
| | | | - Andrew Clair
- Pfizer Inc., 235 East 42 Street, New York, NY 10017 USA
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213
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Macdougall JE, Johnston JM, Lavins BJ, Nelson LM, Williams VSL, Carson RT, Shiff SJ, Shi K, Kurtz CB, Baird MJ, Currie MG, Lembo AJ. An evaluation of the FDA responder endpoint for IBS-C clinical trials: analysis of data from linaclotide Phase 3 clinical trials. Neurogastroenterol Motil 2013; 25:481-6. [PMID: 23384406 DOI: 10.1111/nmo.12089] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Accepted: 01/03/2013] [Indexed: 12/20/2022]
Abstract
BACKGROUND Our objective was to evaluate the performance of the Food and Drug Administration (FDA) Responder Endpoint for clinical trials in IBS-C, using data from two large Phase 3 clinical trials of linaclotide. The FDA interim endpoint requires that, for 50% of trial weeks, patients report ≥30% decrease in Abdominal Pain at its worst and (in the same week) an increase in Complete Spontaneous Bowel Movements (CSBMs) of ≥1 from baseline. METHODS Anchor-based methodology was used to estimate thresholds of clinically meaningful change using symptom-specific patient rating of change questions (PRCQs) and symptom severity questions. The diagnostic accuracy of the FDA Responder Endpoint was assessed using sensitivity/specificity-based methods. KEY RESULTS Using anchor-based methods, the estimates of the clinically meaningful improvement thresholds for Abdominal Pain ranged from 25.9% to 32.4% and thresholds for increase in weekly CSBM rate ranged from 1.4 to 1.6 CSBMs per week. Compared with the symptom-specific PRCQs for patient rating of relief, the FDA Responder Endpoint has a sensitivity of 60.7%, a specificity of 93.5%, and an accuracy of 82.0%. Changing the number of weeks required to be a responder or the percentage improvement in the Abdominal Pain criteria did not result in notable improvement in the accuracy of the FDA Responder Endpoint. CONCLUSIONS & INFERENCES The FDA Responder Endpoint for IBS-C clinical trials represents clinically meaningful improvements in IBS-C symptoms for patients with excellent specificity and reasonable sensitivity.
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214
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Fayers PM, Hays RD. Don't middle your MIDs: regression to the mean shrinks estimates of minimally important differences. Qual Life Res 2013; 23:1-4. [PMID: 23722635 DOI: 10.1007/s11136-013-0443-4] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/21/2013] [Indexed: 11/25/2022]
Abstract
Minimal important differences (MIDs) for patient-reported outcomes (PROs) are often estimated by selecting a clinical variable to serve as an anchor. Then, differences in the clinical anchor regarded as clinically meaningful or important can be used to estimate the corresponding value of the PRO. Although these MID values are sometimes estimated by regression techniques, we show that this is a biased procedure and should not be used; alternative methods are proposed.
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Affiliation(s)
- Peter M Fayers
- Institute of Applied Health Sciences, University of Aberdeen, Aberdeen, UK,
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Abstract
A patient-reported outcome is any report on the status of a patient’s health condition that comes directly from the patient. Clear and meaningful interpretation of patient-reported outcome scores are fundamental to their use as they can be valuable in designing studies, evaluating interventions, educating consumers, and informing health policy makers involved with regulatory, reimbursement, and advisory agencies. Interpretation of patient-reported outcome scores, however, is often not well understood because of insufficient data or lack of experience or clinical understanding to draw from. This article provides an update review on two broad approaches – anchor-based and distributed-based – aimed at enhancing the understanding and meaning of patient-reported outcome scores. Anchor-based approaches include percentages based on thresholds, criterion-group interpretation, content-based interpretation, and clinical important difference. Distributed-based approaches include effect size, probability of relative benefit, and responder analysis and cumulative proportions. A third strategy called mediation analysis, which can elucidate a health condition measured by a patient-reported outcome in the context of an intervention’s mechanism of action, is also highlighted and illustrated. Mediation analysis in the context of interpretation of patient-reported outcome scores is a relatively new development. The logic and rationale of the three methods are expressed generally. While the three approaches themselves are not new, some applications of them taken from their examples published in the past few years are original and coalesced in this article to add real-life implications of the different methodologies in one integrated report.
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Butt Z, Parikh ND, Beaumont JL, Rosenbloom SK, Syrjala KL, Abernethy AP, Benson AB, Cella D. Development and validation of a symptom index for advanced hepatobiliary and pancreatic cancers: the National Comprehensive Cancer Network Functional Assessment of Cancer Therapy (NCCN-FACT) Hepatobiliary-Pancreatic Symptom Index (NFHSI). Cancer 2012; 118:5997-6004. [PMID: 22605658 PMCID: PMC3424375 DOI: 10.1002/cncr.27588] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2012] [Accepted: 03/13/2012] [Indexed: 01/16/2023]
Abstract
BACKGROUND The 45-item Functional Assessment of Cancer Therapy-Hepatobiliary (FACT-Hep) questionnaire assesses health-related quality of life in patients with liver, bile duct, and pancreatic cancers. Although the FACT-Hep was initially derived from patient input, this study's researchers sought to verify adequate coverage of items by soliciting open-ended input from patients with advanced disease. METHODS As part of a larger study in collaboration with the National Comprehensive Cancer Network (NCCN), 50 people (60% male, 80% caucasian, average age 60.4 years) with stage 3 or 4 hepatobiliary or pancreatic cancer were recruited. Participants generated and ranked up to 10 important symptoms and concerns that physicians should monitor when assessing the value of chemotherapy. Patients were also able to provide open-ended, qualitative information that was evaluated systematically. Ten expert physicians also provided input on priority symptoms. RESULTS The resulting 18-item NCCN-FACT Hepatobiliary-Pancreatic Symptom Index (NFHSI-18) demonstrated high internal consistency (α = .89) and moderate to strong correlations with measures of physical well-being (ρ = .76), emotional well-being (ρ = 0.52), and functional well-being (ρ = 0.57). Scores on the NFHSI-18 were also highly correlated with the original hepatobiliary scale of the FACT-Hep (ρ = .82; all P < .001). Compared with patients with better performance status, patients with poor performance status had worse NFHSI-18 symptom scores, F(3,47) = 9.74; P = .0003. CONCLUSIONS The NFHSI-18 assesses symptoms of importance to patients with hepatobiliary and pancreatic cancers and demonstrates promising measurement properties. The scale is a good candidate for brief symptom assessment in clinical trials.
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Affiliation(s)
- Zeeshan Butt
- Department of Medical Social Sciences, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA.
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217
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Abstract
Ensuring quality of life (QOL) while maintaining glycemic control within targets is an important challenge in type 1 and type 2 diabetes treatment. For children with diabetes, QOL includes enjoying meals, feeling safe in school, and perceiving positive, supportive relationships with parents, siblings, and friends. Yet many treatment-related and psychosocial barriers can interfere with a child's QOL and their ability to manage diabetes effectively. Diabetes management also imposes considerable lifestyle demands that are difficult and often frustrating for children to negotiate at a young age. Recent advances in diabetes medications and technologies have improved glycemic control in children with diabetes. Two widely used technologies are the insulin pump and continuous glucose monitoring (CGM) system. These technologies provide patients with more flexibility in their daily life and information about glucose fluctuations. Several studies report improvements in glycemic control in children with type 1 diabetes using the insulin pump or sensor-augmented pump therapy. Importantly, these technologies may impact QOL for children and families with diabetes, although they are rarely used or studied in the treatment of children with type 2 diabetes. Further, emerging closed loop and web- and phone-based technologies have great potential for supporting diabetes self-management and perhaps QOL. A deeper understanding and appreciation of the impact of diabetes technology on children's and parents' QOL is critical for both the medical and psychological care of diabetes. Thus, the purpose of this review is to discuss the impact of new diabetes technologies on QOL in children, adolescents and families with type 1 diabetes.
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Affiliation(s)
- Masakazu Hirose
- Joslin Diabetes Center, Boston, Massachusetts
- Harvard Medical School, Boston, Massachusetts
| | - Elizabeth A. Beverly
- Joslin Diabetes Center, Boston, Massachusetts
- Harvard Medical School, Boston, Massachusetts
| | - Katie Weinger
- Joslin Diabetes Center, Boston, Massachusetts
- Harvard Medical School, Boston, Massachusetts
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Engelhart L, Nelson L, Lewis S, Mordin M, Demuro-Mercon C, Uddin S, McLeod L, Cole B, Farr J. Validation of the Knee Injury and Osteoarthritis Outcome Score subscales for patients with articular cartilage lesions of the knee. Am J Sports Med 2012; 40:2264-72. [PMID: 22962288 DOI: 10.1177/0363546512457646] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND The Knee Injury and Osteoarthritis Outcome Score (KOOS) assesses acute and chronic knee injuries or early-onset osteoarthritis in young, active patients. The United States Food and Drug Administration guidelines recommend that patient-reported outcome instruments used to support clinical trial label claims should demonstrate content validity using patient input and have acceptable psychometric properties in the target population. To use the KOOS subscales in safety and efficacy trials assessing new treatments for patients with articular cartilage lesions, additional validation work, using input from patients with articular cartilage lesions, was necessary. PURPOSE Qualitative and quantitative evaluations of the KOOS subscales' validity among patients with articular cartilage lesions were conducted to support their use as clinically meaningful end points in clinical trials. STUDY DESIGN Cohort study (diagnosis); Level of evidence, 2. METHODS For qualitative analysis, cognitive interviews involving concept elicitation and cognitive debriefing with the KOOS items were conducted with 15 participants aged 25 to 52 years. Participants either were candidates for cartilage repair or had undergone cartilage repair 6 months or more before the study. For the quantitative analysis, a psychometric evaluation of the KOOS was conducted with clinical trial data from 54 patients, aged 18 to 55 years, evaluating the Cartilage Autograft Implantation System in the United States (n = 29) and the European Union (n = 25). Data were collected before surgery and at 7 postsurgical visits up to 12 months. Internal consistency and test-retest reliability, construct validity, responsiveness, and estimates of the minimal detectable change (MDC) were assessed. Test-retest reliability was assessed using data from months 2 and 3 on a subset of stable patients. RESULTS Qualitative research confirmed that concepts measured on the KOOS are important to patients with articular cartilage lesions. Most participants reported the KOOS was comprehensive and appropriate. In the quantitative research, KOOS subscales showed excellent internal consistency reliability (range, .74-.97 at baseline) and test-retest reliability (range, .78-.82). Construct validity results supported hypothesized relationships, with significant correlations (r ≥ .50) in the expected directions. Responsiveness analyses demonstrated excellent sensitivity to change; standardized response means ranged from 0.8 to 1.2, and MDC estimates ranged from 7.4 to 12.1. CONCLUSION The study results support the use of the KOOS subscales among patients with articular cartilage lesions.
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Cappelleri JC, Zou KH, Bushmakin AG, Carlsson MO, Symonds T. Cumulative response curves to enhance interpretation of treatment differences on the Self-Esteem And Relationship questionnaire for men with erectile dysfunction. BJU Int 2012; 111:E115-20. [PMID: 23017067 DOI: 10.1111/j.1464-410x.2012.11489.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
UNLABELLED What's known on the subject? and What does the study add? Studies on erectile dysfunction (ED) therapies rely heavily on patient-reported outcomes (PROs) to measure efficacy on treatment response. A challenge when using PROs is interpretation of the clinical meaning of changes in scores. A responder analysis provides a threshold score to indicate whether a change in score qualifies a patient as a responder. However, a major consideration with responder analysis is the sometimes arbitrary nature of defining the threshold for a response. By contrast, cumulative response curves (CRCs) display patient response rates over a continuum of possible thresholds, thus eliminating problems with a rigid threshold definition, allowing for a variety of response thresholds to be examined simultaneously, and encompassing all data. With respect to the psychosocial factors addressed in the Self-Esteem And Relationship questionnaire in ED, CRCs clearly, distinctly, and meaningfully highlighted the favourable profiles of responses to sildenafil compared with placebo. CRCs for PROs in urology can provide a clear, transparent and meaningful visual depiction of efficacy data that can supplement and complement other analyses. OBJECTIVE To use cumulative response curves (CRCs) to enrich meaning and enhance interpretation of scores on the Self-Esteem And Relationship (SEAR) questionnaire with respect to treatment differences for men with erectile dysfunction (ED). PATIENTS AND METHODS This post hoc analysis used data from all patients who took at least one dose of study drug and had at least one post-baseline efficacy evaluation in a previously published 12-week, multicentre, randomized, double-blind, placebo-controlled trial of flexible-dose (25, 50, or 100 mg) sildenafil citrate (Viagra) in adult men with ED who had scored ≤ 75 out of 100 on the Self-Esteem subscale of the SEAR questionnaire. CRCs were used on the numeric change in transformed SEAR scores from baseline to end-of-study for each SEAR component. The horizontal axis of the CRC represented change from baseline on the SEAR score, and the vertical axis represented the percentage of patients experiencing that change or greater. The differences between CRCs for the sildenafil group vs the placebo group were assessed using the Kolmogorov-Smirov test. RESULTS For each of the SEAR components, there was essentially no overlap in the CRCs between the sildenafil group (n = 113) and placebo group (n = 115 or 116, depending on the component), showing that a greater percentage of sildenafil recipients compared with placebo recipients had a more favourable change across the spectrum of response thresholds (P ≤ 0.01). Previous research showed that a 10-point score increase is the minimal clinically meaningful improvement for most SEAR components. In the sildenafil vs placebo groups, a ≥10-point score increase occurred in 72 vs 37% of patients, respectively, on the Sexual Relationship Satisfaction domain, 71 vs 41% on the Confidence domain, 76 vs 49% on the Self-Esteem subscale, 60 vs 44% on the Overall Relationship Satisfaction subscale, and 75 vs 38% on the Overall score. CONCLUSIONS With respect to the psychosocial factors addressed in the SEAR questionnaire, CRCs clearly, distinctly, and meaningfully highlighted the favourable profiles of responses to sildenafil compared with placebo. CRCs for patient-reported outcomes in urology can provide a clear, transparent, and meaningful visual depiction of efficacy data that can supplement and complement other analyses.
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Alemayehu D, Cappelleri JC. Conceptual and Analytical Considerations toward the Use of Patient-Reported Outcomes in Personalized Medicine. AMERICAN HEALTH & DRUG BENEFITS 2012; 5:310-317. [PMID: 24991329 PMCID: PMC4046457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
BACKGROUND Patient-reported outcomes (PROs) can play an important role in personalized medicine. PROs can be viewed as an important fundamental tool to measure the extent of disease and the effect of treatment at the individual level, because they reflect the self-reported health state of the patient directly. However, their effective integration in personalized medicine requires addressing certain conceptual and methodological challenges, including instrument development and analytical issues. OBJECTIVES To evaluate methodological issues, such as multiple comparisons, missing data, and modeling approaches, associated with the analysis of data related to PRO and personalized medicine to further our understanding on the role of PRO data in personalized medicine. DISCUSSION There is a growing recognition of the role of PROs in medical research, but their potential use in customizing healthcare is not widely appreciated. Emerging insights into the genetic basis of PROs could potentially lead to new pathways that may improve patient care. Knowledge of the biologic pathways through which the various genetic predispositions propel people toward negative or away from positive health experiences may ultimately transform healthcare. Understanding and addressing the conceptual and methodological issues in PROs and personalized medicine are expected to enhance the emerging area of personalized medicine and to improve patient care. This article addresses relevant concerns that need to be considered for effective integration of PROs in personalized medicine, with particular reference to conceptual and analytical issues that routinely arise with personalized medicine and PRO data. Some of these issues, including multiplicity problems, handling of missing values-and modeling approaches, are common to both areas. It is hoped that this article will help to stimulate further research to advance our understanding of the role of PRO data in personalized medicine. CONCLUSION A robust conceptual framework to incorporate PROs into personalized medicine can provide fertile opportunity to bring these two areas even closer and to enhance the way a specific treatment is attuned and delivered to address patient care and patient needs.
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Shen J, Johnston M, Hays RD. Asthma outcome measures. Expert Rev Pharmacoecon Outcomes Res 2011; 11:447-53. [PMID: 21831026 DOI: 10.1586/erp.11.48] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Asthma is a common chronic disease with underlying inflammation of the airway. Advances in science have led to increased understanding of the heterogeneous nature of asthma and its complex mechanisms. Traditionally, asthma-practice guidelines have focused on optimizing lung function and the US FDA has required increases in lung function and reduction of exacerbation as primary outcomes in clinical trials of new asthma therapeutics. Improved lung function is a critical indicator of bronchodilator therapy, but the importance of long-term asthma control while maintained on controller medication is increasingly emphasized. The NIH asthma guidelines suggest the use of patient-reported outcomes, including health-related quality-of-life measures, to assess asthma control. Clinical practices and research studies concerning asthma can benefit from harmonizing the major outcome measures so that comparisons across studies can be made. In this article, we review common asthma outcome measures with a focus on recent efforts to harmonize outcomes for therapeutic clinical trials in asthma.
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Affiliation(s)
- Joannie Shen
- Air Pollution and Respiratory Health Branch/National Center for Environmental Health/Centers for Disease Control and Prevention, 1600 Clifton Road, Atlanta, GA 30333, USA.
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Feeny D, Spritzer K, Hays RD, Liu H, Ganiats TG, Kaplan RM, Palta M, Fryback DG. Agreement about identifying patients who change over time: cautionary results in cataract and heart failure patients. Med Decis Making 2011; 32:273-86. [PMID: 22009666 DOI: 10.1177/0272989x11418671] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
BACKGROUND Preference-based measures of health-related quality of life all use the same dead = 0.00 to perfect health = 1.00 scale, but there are substantial differences among measures. OBJECTIVE The objective was to examine agreement in classifying patients as better, stable, or worse. METHODS The EQ-5D, Health Utilities Index Mark 2 and Mark 3, Quality of Well-Being-Self-Administered scale, Short-Form 36 (Short-Form 6D), and disease-targeted measures were administered prospectively in 2 clinical cohorts. The study was conducted at academic medical centers: University of California, Los Angeles; University of California, San Diego; University of Wisconsin-Madison; and University of Southern California. Patients undergoing cataract extraction surgery with lens replacement completed the 25-item National Eye Institute Visual Function Questionnaire (NEI-VFQ-25). Patients newly referred to congestive heart failure specialty clinics completed the Minnesota Living with Heart Failure Questionnaire (MLHF). In both cohorts, subjects completed surveys at baseline and at 1 and 6 months. The NEI-VFQ-25 and MLHF were used as gold standards to assign patients to categories of change. Agreement was assessed using κ. RESULTS There were 376 cataract patients recruited. Complete data for baseline and the 1-month follow-up were available on all measures for 210 cases. Using criteria specified by Altman, agreement was poor for 6 of 9 pairs of comparisons and fair for 3 pairs. There were 160 heart failure patients recruited. Complete data for baseline and the 6-month follow-up were available for 86 cases. Agreement was negligible for 5 pairs and fair for 1. The study was conducted on selected patients at a few academic medical centers. CONCLUSIONS The results underscore the lack of interchangeability among different preference-based measures.
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Affiliation(s)
- David Feeny
- The Center for Health Research, Kaiser Permanente Northwest and Health Utilities Incorporated, Portland, OR (DF)
| | - Karen Spritzer
- Department of Medicine, University of California, Los Angeles (KS, RDH)
| | - Ron D Hays
- Department of Medicine, University of California, Los Angeles (KS, RDH)
| | - Honghu Liu
- School of Dentistry, University of California, Los Angeles (HL)
| | - Theodore G Ganiats
- Department of Family and Preventive Medicine, University of California, San Diego (TGG)
| | - Robert M Kaplan
- Department of Health Services Research, University of California, Los Angeles (RMK)
| | - Mari Palta
- Department of Population Health Sciences, University of Wisconsin-Madison (MP, DGF)
| | - Dennis G Fryback
- Department of Population Health Sciences, University of Wisconsin-Madison (MP, DGF)
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