The clinical value and meaning of health-related quality-of-life outcomes in oncology

doi:10.1017/CBO9780511545856.019

19 - The clinical value and meaning of health-related quality-of-life outcomes in oncology

Published online by Cambridge University Press: 18 December 2009

David Osoba B.Sc., M.D., F.R.C.P.C.

Edited by

Joseph Lipscomb ,

Carolyn C. Gotay and

Claire Snyder

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David Osoba B.Sc., M.D., F.R.C.P.C.: Affiliation:
Professor of Psychiatry and Behavioral Science QOL Consulting, West Vancouver, BC, Canada
Joseph Lipscomb: Affiliation:
National Cancer Institute, Bethesda, Maryland
Carolyn C. Gotay: Affiliation:
Cancer Research Center, Hawaii
Claire Snyder: Affiliation:
National Cancer Institute, Bethesda, Maryland

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Summary

The clinical value of measuring health-related quality of life

Common clinical outcomes

Before the modern era of objectivity in clinical oncology research, reports of the effects of therapy were often based on an individual clinician's experience (case reports and series). As awareness of the advantages of research objectivity increased, several clinical outcomes, including overall survival, median survival time, tumor-free survival, progression-free survival, time to progression, and frequency and duration of tumor response, were accepted and widely used. Of these, overall survival is considered as being the “hardest” endpoint, i.e., least likely to be subject to misinterpretation, and tumor response the “softest” endpoint.,

In addition, the concept of levels of evidence was introduced.– The highest level of evidence, Level I, consists of data from meta-analysis of several phase III randomized controlled clinical trials (RCTs) or a very large, phase III trial containing several hundred patients. The lowest level of evidence, Level IV, is data derived from small, uncontrolled case series or reports. Currently, institutions collaborate with each other to enroll the large number of patients needed to produce Level I evidence, and eligibility criteria for patient enrollment are increasingly stringent in order to control as many clinical variables as possible.

The interpretation of clinical trials has been aided by the collection of toxicity data. As with response and survival data, there has been an attempt to become more comprehensive by collecting very detailed information with uniform grading systems.

Type: Chapter
Information: Outcomes Assessment in Cancer
Measures, Methods and Applications
, pp. 386 - 405

DOI: https://doi.org/10.1017/CBO9780511545856.019 [Opens in a new window]

Publisher: Cambridge University Press

Print publication year: 2004

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References

Simon, R. (1993). Design and conduct of clinical trials. In Cancer. Principles and Practice of Oncology, (Fourth Edition), ed. V. T. DeVita Jr., S. Hellman, S. Rosenberg, pp. 416–40. Philadelphia, PA: JB Lippincott Co

Warr, D., McKinney, S., Tannock, I. (1984). Influence of measurement error on assessment of response to anticancer chemotherapy: proposal for new criteria of tumor responseJournal of Clinical Oncology 2:1041–6CrossRef Google Scholar PubMed

Cook, D. J., Guyatt, G. H., Laupacis, A., Sackett, D. L. (1992). Rules of evidence and clinical recommendation on the use of antithrombotic agentsChest 102 (Suppl. 4):305S–11SGoogle Scholar

Sackett, D. L. (1993). Rules of evidence and clinical recommendations for the management of patientsCanadian Journal of Cardiology 9:487–9Google Scholar PubMed

Sackett, D. L., Cook, D. J. (1993). Can we learn anything from small trials?Annals of the New York Academy of Sciences 703:25–31CrossRef Google Scholar PubMed

Franklin, H. R., Simonetti, G. P., Dubbelman, A. C.et al. (1994). Toxicity grading systems. A comparison between the WHO scoring system and the Common Toxicity Criteria when used for nausea and vomitingAnnals of Oncology 5:113–17CrossRef Google Scholar PubMed

Karnofsky, D. A., Abelman, W. H., Craver, L. F., Burchenal, J. H. (1948). The use of nitrogen mustards in the palliative treatment of carcinomaCancer 1:634–563.0.CO;2-L>CrossRef Google Scholar

Zubrod, C. G., Schneiderman, M., Frei, E. III. et al. (1960). Appraisal of methods for the study of chemotherapy of cancer in man: comparative therapeutic trial of nitrogen mustard and triethylene thiophosphoramideJournal of Chronic Diseases 11:7–33CrossRef Google Scholar

Ware, J. E. Jr., (1991). Measuring functioning, well-being, and other generic health concepts. In Effect of Cancer on Quality of Life, ed. D. Osoba, pp. 7–23. Boca Raton, FL: CRC Press

Slevin, M. L., Plant, H., Lynch, D., Drinkwater, J., Gregory, W. M. (1988). Who should measure quality of life, the doctor or the patient?British Journal of Cancer 57:109–12CrossRef Google Scholar PubMed

Sneeuw, K. C. A., Aaronson, N. K., Sprangers, M. A. G., Detmar, S. B., Wever, L. D. V., Schornagel, J. H. (1998). Comparison of patient and proxy EORTC QLQ-C30 ratings in assessing the quality of life of cancer patients.Journal of Clinical Epidemiology 51:617–31CrossRef Google Scholar PubMed

Osoba, D., Rusthoven, J. J., Turnbull, K. A., Evans, W. K., Shepherd, F. A. (1998). Combination chemotherapy with bleomycin, etoposide, and cisplatin in metastatic non-small-cell lung cancer.Journal of Clinical Oncology 3:1478–85CrossRef Google Scholar

Stephens, R. J., Hopwood, P., Girling, D. J. (1999). Defining and analysing symptom palliation in cancer clinical trials: a deceptively difficult exercise.British Journal of Cancer 79:533–44CrossRef Google Scholar PubMed

Savage, C., Pater, J. L., Tu, D., Norris, B. (2002). He said/she said: how well do common toxicity criteria and quality of life agree on patient symptoms?Proceedings of the American Society of Clinical Oncology 21:382a (abstract 1540)Google Scholar

Osoba, D. (1991). Measuring the effect of cancer on quality of life. In Effect of Cancer on Quality of Life, ed. D. Osoba, pp. 25–40. Boca Raton, FL: CRC Press

Osoba, D., Aaronson, N. K., Till, J. E. (1999) A practical guide for selecting quality-of-life measures in clinical trials and practice. In Effect of Cancer on Quality of Life, ed. D. Osoba, pp. 89–104. Boca Raton, FL: CRC Press

Guyatt, G. H., Veldhuzen Van Zanten, S. J. O., Feeny, D. H., Patrick, D. L.. (1989). Measuring quality of life in clinical trials: a taxonomy and review.Canadian Medical Association Journal 140:1441–8Google Scholar PubMed

Jaeschke, R., Guyatt, G. D., Cook, D. (1992). Quality of life instruments in the evaluation of new drugs.Pharmacoeconomics 1:84–94CrossRef Google Scholar PubMed

Osoba, D. (1995). Measuring the effect of cancer on health-related quality of lifePharmacoeconomics 7:308–19CrossRef Google Scholar PubMed

Mackworth, N., Fobair, P., Prados, M. D. (1992). Quality of life self-reports from 100 brain tumor patients: comparisons with Karnofsky Performance ScoresJournal of Neuro-Oncology 14:243–53CrossRef Google Scholar PubMed

Schaafsma, J., Osoba, D. (1994). The Karnofsky performance status scale re-examined: a cross-validation with the EORTC-C30Quality of Life Research 3:413–24CrossRef Google Scholar PubMed

Hjermstad, M. J., Fayers, P. M., Bjordal, K., Kaasa, S. (1998). Health related quality of life in the general Norwegian population assessed by the European Organization for Research and Treatment of Cancer Core Quality of Life Questionnaire: the QLQ-C30(+3).Journal of Clinical Oncology 16:1188–96CrossRef Google Scholar PubMed

Klee, M., Roenvald, M., Machin, D. (1997). Quality of Life of Danish women: population-based norms for the EORTC QLQ-C30.Quality of Life Research 6:27–34CrossRef Google Scholar PubMed

Michelson, H., Bolund, C., Nilsson, B., Brandberg, Y. (2000). Health-related quality of life measured by the EORTC QLQ-C30 — reference values from a large sample of the Swedish population.Acta Oncologica 39:477–84Google Scholar PubMed

Gandek, B., Ware, J. E., Aaronson, N. K.et al. (1998). Tests of data quality, scaling assumptions, and reliability of the SF-36 in eleven countries: results from the IQOLA project.Journal of Clinical Epidemiology 51:1149–58CrossRef Google Scholar PubMed

Fayers, P., Weeden, S., Curran, D. (1998). EORTC QLQ-C30 Reference Values. Brussels: EORTC Quality of Life Study Group, EORTC Data Centre

Allen-Mersch, T. G., Earlam, S., Fordy, C., Abrams, K., Houghton, J. (1994). Quality of life and survival with continuous hepatic-artery floxuridine infusion for colorectal liver metastasesLancet 344:1255–60CrossRef Google Scholar

Clavel, M., Soukop, M., Greenstreet, Y. C. A., (1993). Improved control of emesis and quality of life with ondansetron in breast cancerOncology 50:180–5CrossRef Google Scholar PubMed

Coates, A., Gebski, V., Bishop, J. F.et al. (1987). Improving the quality of life during chemotherapy for advanced breast cancer. A comparison of intermittent and continuous treatment strategies.New England Journal of Medicine 317:1490–5CrossRef Google Scholar PubMed

Osoba, D., Brada, M., Yung, W. K. A., Prados, M. (2000). Health-related quality of life in patients treated with temozolomide versus procarbazine for recurrent glioblastoma multiforme.Journal of Clinical Oncology 18:1481–91CrossRef Google Scholar PubMed

Osoba, D., Brada, M., Yung, W. K. A., Prados, M. (2000). Health-related quality of life in patients with anaplastic astrocytoma during treatment with temozolomide.European Journal of Cancer 36:1788–95CrossRef Google Scholar PubMed

Osoba, D., Northfelt, D. W., Budd, D. W., Himmelberger, D. (2001). Effect of treatment on health-related quality of life in AIDS-related Kaposi's sarcoma; a randomized trial of pegylated liposomal doxorubicin versus doxorubicin, bleomycin and vincristine.Cancer Investigation 19:573–80CrossRef Google Scholar PubMed

Murray, N., Livingston, R. B., Shepherd, F. A.et al. (1999). Randomized study of CODE versus alternating CAV/EP for extensive-stage small-cell lung cancer: An intergroup study of the National Cancer Institute of Canada Clinical Trials Group and the Southwest Oncology Group.Journal of Clinical Oncology 17:2300–8CrossRef Google Scholar

Hürny, C., Bernhard, J., Coates, A. S.et al. (1996). Impact of adjuvant therapy on quality of life in women with node-positive operable breast cancer. International Breast Cancer Study Group.Lancet 347:1279–84CrossRef Google Scholar PubMed

Fairclough, D. L., Fetting, J. H., Cella, D., Wonson, W., Moinpour, C. M. (1999). Quality of life and quality adjusted survival for breast cancer patients receiving adjuvant chemotherapy. Eastern Cooperative Oncology Group (ECOG).Quality of Life Research 8:723–31CrossRef Google Scholar PubMed

Osoba, D. (1999). What has been learned from measuring health-related quality of life in clinical oncology.European Journal of Cancer 35:1565–70CrossRef Google Scholar PubMed

Cutler, D. M., Richardson, E. (1997). Measuring the health of the U.S. population. In Brookings Papers on Economic Activity: Microeconomics, ed. M. C. Bailey, P. C. Reiss, C. Winston, pp. 217–71. Washington, DC: Brookings InstituteCrossRef

Osoba, D., Zee, B., Sadura, A., Pater, J., Quirt, I. (1993). Measurement of quality of life in an adjuvant trial of gamma interferon versus levamisole in malignant melanoma. In Adjuvant Therapy of Cancer VII, ed. S. E. Salmon, pp. 412–16. Philadelphia, PA: JB Lippincott Co

Coates, A., Gebski, V., Signorini, D.et al. (1992). Prognostic value of quality-of-life scores during chemotherapy for advanced breast cancer. Australian New Zealand Breast Cancer Trials Group.Journal of Clinical Oncology 10:1833–8CrossRef Google Scholar PubMed

Coates, A., Porzsolt, F., Osoba, D. (1997). Quality of life in oncology practice: prognostic value of EORTC QLQ-C30 scores in patients with advanced malignancy.European Journal of Cancer 33:1025–30CrossRef Google Scholar PubMed

Coates, A. S., Hürny, C., Peterson, H. F.et al. (2000). Quality-of-life scores predict outcome in metastatic but not early breast cancer.Journal of Clinical Oncology 18:3768–74CrossRef Google Scholar

Coates, A. S., Thomson, D., McLeod, G. R. M.et al. (1993). Prognostic value of quality of life scores in a trial of chemotherapy with or without interferon in patients with metastatic malignant melanoma.European Journal of Cancer 29A:1731–4CrossRef Google Scholar PubMed

Earlam, S., Glover, C., Fordy, C., Burke, D., Allen-Mersh, T. G. (1996). Relation between tumour size, quality of life, and survival in patients with colorectal liver metastases.Journal of Clinical Oncology 14:171–5CrossRef Google Scholar PubMed

Kaasa, S., Mastekaasa, A., Lund, E. (1989). Prognostic factors for patients with inoperable non-small cell lung cancer, limited disease.Radiotherapy Oncology 15:235–42CrossRef Google Scholar PubMed

Ganz, P. A., Lee, J. J., Siau, J. (1991). Quality of life assessment. An independent prognostic variable for survival in lung cancer.Cancer 67:3131–53.0.CO;2-4>CrossRef Google Scholar PubMed

Blazeby, J. M., Brookes, S. T., Alderson, D. (2001). The prognostic value of quality of life scores during treatment for oesophageal cancer.Gut 49:227–30CrossRef Google Scholar PubMed

Dancey, J., Zee, B., Osoba, D.et al. (1997). Quality of life scores: an independent prognostic variable in a general population of cancer patients receiving chemotherapy.Quality of Life Research 6:151–8CrossRef Google Scholar

Herndon, J. E. Jr., Fleishman, S., Kornblith, A. B., Kosty, M., Green, M. R., Holland, J. (1999). Is quality of life predictive of the survival of patients with advanced nonsmall cell lung carcinoma?Cancer 85:333–403.0.CO;2-Q>CrossRef Google Scholar PubMed

Medical Research Council Working Party (1993). A randomized trial of three or six courses of etoposide, cyclophosphamide, methotrexate and vincristine or six courses of etoposide and ifosfamide in small cell lung cancer. (SCLC) II: quality of life.British Journal of Cancer 68:1157–66CrossRef

Tannock, I. F., Osoba, D., Stockler, M. R.et al. (1996). Chemotherapy with mitoxantrone plus prednisone or prednisone alone for symptomatic hormone-resistant prostate cancer; a Canadian randomized trial with palliative end points.Journal of Clinical Oncology 14:1756–64CrossRef Google Scholar PubMed

Osoba, D., Tannock, I. F., Ernst, S., Neville, J. (1999). Health-related quality of life in men with metastatic prostate cancer treated by prednisone alone or mitoxantrone and prednisone.Journal of Clinical Oncology 17:1654–63CrossRef Google Scholar PubMed

Demetri, G. D., Kris, M., Wade, J., Degos, L., Cella, D. (1998). Quality-of-life benefit in chemotherapy patients treated with epoetin alfa is independent of disease response or tumor type: results from a prospective community oncology study.Journal of Clinical Oncology 16:3412–25CrossRef Google Scholar PubMed

Rowland, K. M. Jr., Loprinzi, C. L., Shaw, E. G.et al. (1996). Randomized double-blind placebo-controlled trial of cisplatin and etoposide plus megestrol acetate in extensive-stage small-cell lung cancer: a North Central Cancer Treatment Group Study.Journal of Clinical Oncology 14:135–41CrossRef Google Scholar PubMed

Simons, J. P., Aaronson, N. K., Vansteenkiste, J. F.et al. (1996). Effects of medroxyprogesterone acetate on appetite, weight, and quality of life in advanced-stage non-hormone-sensitive cancer: a placebo-controlled multicentre study.Journal of Clinical Oncology 14:1077–84CrossRef Google Scholar

Bruera, E., Ernst, S., Hagen, N.et al. (1998). Effectiveness of megestrol acetate in patients with advanced cancer: a randomized, double-blind, crossover study.Cancer Prevention and Control 2:74–8Google Scholar PubMed

Porter, A. T., McEwan, A. J. B., Powe, J. E.et al. (1993). Results of a randomized phase III trial to evaluate the efficacy of strontium-89 adjuvant to local field external beam irradiation in the management of endocrine resistant metastatic prostate cancer.International Journal of Radiation Oncology, Biology, and Physics 25:805–13CrossRef Google Scholar PubMed

Seymour, M. T., Slevin, M. L., Kerr, D. J.et al. (1996). Randomized trial assessing the addition of interferon α-2a to fluorouracil and leucovorin in advanced colorectal cancer.Journal of Clinical Oncology 14:2282–8CrossRef Google Scholar PubMed

Ganz, P. A. (2001). Impact of tamoxifen adjuvant therapy on symptoms, functioning, and quality of life.Journal of the National Cancer Institute Monograph 30:130–4CrossRef Google Scholar

Moinpour, C. M., Lovato, L. C., Thompson, I. M.et al. (2000). Profile of men randomized to the prostate cancer prevention trial: baseline health-related quality of life, urinary and sexual functioning, and health behaviors.Journal of Clinical Oncology 18:1942–53CrossRef Google Scholar PubMed

Hays, R. D., Anderson, R., Revicki, D. (1993). Psychometric considerations in evaluating health-related quality of life measures.Quality of Life Research 2:441–9CrossRef Google Scholar PubMed

Hays, R. D., Anderson, R. T., Revicki, D. (1998). Assessing reliability and validity of measurement in clinical trials. In Quality of Life Assessment in Clinical Trials, ed. M. J. Staquet, R. D. Hays, P. M. Fayers, pp. 169–23. Oxford: Oxford University Press

Revicki, D. A., Kaplan, R. M. (1993). Relationship between psychometric and utility-based approaches to the measurement of health-related quality of life.Quality of Life Research 2:477–87CrossRef Google Scholar PubMed

Torrance, G. W. (1986). Measurement of health state utilities for economic appraisal.Journal of Health Economics 5:1–30CrossRef Google Scholar PubMed

Torrance, G. W., Feeny, D. (1989). Utilities in quality-adjusted life years.International Journal of Technology Assessment in Health Care 5:559–75CrossRef Google Scholar PubMed

Kaplan, R. M., Feeny, D., Revicki, D. A. (1993). Methods for assessing relative importance in preference based outcome measures.Quality of Life Research 2:467–75CrossRef Google Scholar PubMed

Feeny, this volume, Chapter 4

O'Brien, this volume, Chapter 25

Detmar, S., Muller, M. J., Schornagel, J. H., Wever, L. D., Aaronson, N. K. (2002). The role of health-related quality of life considerations in palliative chemotherapy treatment decisionsJournal of Clinical Oncology 20:1056–62CrossRef Google Scholar PubMed

Levine, M. N., Gafni, A., Markham, B., MacFarlane, D. (1992). A bedside decision instrument to elicit a patient's preference concerning adjuvant chemotherapy for breast cancer.Annals of Internal Medicine 117:53–8CrossRef Google Scholar PubMed

Whelan, T. J., Levine, M. N., Gafni, A.et al. (1995). Breast irradiation postlumpectomy: development and evaluation of a decision instrument.Journal of Clinical Oncology 13:847–53CrossRef Google Scholar PubMed

Osoba, D. (2002). A taxonomy of the uses of health-related quality of life (HRQOL) instruments in cancer care and the clinical meaningfulness of the results.Medical Care 40 (Suppl. 3):S31–8CrossRef Google Scholar PubMed

Detmar, S. B., Aaronson, N. K. (1998). Quality of life assessment in daily clinical oncology practice: a feasibility study.European Journal of Cancer 34:1181–6CrossRef Google Scholar PubMed

Velikova, G., Brown, J. M., Smith, A. B., Selby, P. J. (2002). Computer-based quality of life questionnaires may contribute to doctor—patient interactions in oncology.British Journal of Cancer 86:51–9CrossRef Google Scholar

Murray, C. J. L., Lopez, A. D. (1997). Global mortality, disability, and the contribution of risk factors: Global Burden of Disease Study.Lancet 349:1436–42CrossRef Google Scholar PubMed

World Health Organization (2000). The World Health Report 2000: Health Systems: Improving Performance. Geneva: World Health Organization

Goldie, A. J., Kuntz, K. M., Weinstein, M. C., Freedberg, K. A., Palefsky, J. M. (2000). Cost-effectiveness of screening for anal squamous intraepithelial lesions and anal cancer in human immunodeficiency virus-negative homosexual and bisexual men.American Journal of Medicine 108:634–41CrossRef Google Scholar PubMed

Neilson, A. R., Whynes, D. K. (1995). Cost-effectiveness of screening for colorectal cancer: a simulation model.IMA Journal of Mathematically Applied Medical Biology 12:355–67CrossRef Google Scholar PubMed

Norum, J. (2000). Adjuvant cyclophosphamide, methotrexate, fluorouracil (CMF) in breast cancer — is it cost-effective?Acta Oncologica 39:33–9CrossRef Google Scholar PubMed

Brown, M. L, Lipscomb, J., Snyder, C. (2001). The burden of illness in cancer: economic cost and quality of life.Annual Review of Public Health 22:91–113CrossRef Google Scholar PubMed

Lydick, E., Epstein, R. S. (1993). Interpretation of quality of life changes.Quality of Life Research 2:221–6CrossRef Google Scholar PubMed

Osoba, D., Rodrigues, G., Myles, J., Zee, B., Pater, J. (1998). Interpreting the significance of changes in health-related quality-of-life scores.Journal of Clinical Oncology 16:139–44CrossRef Google Scholar PubMed

Bernhard, J., Gelber, R. D., ed. (1998). Workshop on Missing Data in Quality of Life Research in Cancer Clinical Trials: Practical and Methodological Issues. Statistics of Medicine 17:511–7963.0.CO;2-C>CrossRef

Fairclough, D. L. (2002). Design and Analysis of Quality of Life Studies in Clinical Trials. Boca Raton, FL: Chapman & Hall/CRC

Sloan, this volume, Chapter 18, pp. 362–85

Cohen, J. (1977). Statistical Power Analysis for the Behavioural Sciences. New York: Academic Press

Kazis, L. E., Anderson, J. J., Meenan, R. F. (1989). Effect sizes for interpreting changes in health status.Medical Care 27 (Suppl. 3):S178–89CrossRef Google Scholar PubMed

King, M. T. (1996). The interpretation of scores from the EORTC Quality of Life Questionnaire QLQ-C30.Quality of Life Research 5:555–67CrossRef Google Scholar PubMed

Jacobson, N. S., Roberts, L. J., Berns, S. B., McGlinchey, J. B. (1999). Methods for defining and determining the clinical significance of treatment effects: description, application and alternatives.Journal of Consulting Clinical Psychology 67:300–7CrossRef Google Scholar PubMed

Salsburg, D. S., Turner, R. S. (1992). Defining clinically meaningful units of change for health outcome research.Quality of Life Newsletter 3:1Google Scholar

Wyrwich, K., Nienaber, N. A., Tierney, W., Wolinsky, F. (1999). Linking clinical relevance and statistical significance in evaluating intra-individual changes in health-related quality of life.Medical Care 37:469–78CrossRef Google Scholar PubMed

Wyrwich, K., Tierney, W., Wolinsky, F. (1999). Further evidence supporting a SEM-based criterion for identifying meaningful intra-individual changes in health-related quality of life.Journal of Clinical Epidemiology 52:861–73CrossRef Google Scholar PubMed

Wyrwich, K. W., Wolinsky, F. G. (2000). Identifying meaningful intra-individual change standards for health-related quality of life measures.Journal of Evaluating Clinical Practice 6:39–45CrossRef Google Scholar PubMed

Jaeschke, R., Singer, J., Guyatt, G. H. (1989). Measurement of health status. Ascertaining the minimal clinically important difference.Controlled Clinical Trials 10:407–15CrossRef Google Scholar PubMed

Juniper, E. D., Guyatt, G. H., Willan, A., Griffith, L. E. (1994). Determining a minimal important change in a disease-specific quality of life questionnaire.Journal of Clinical Epidemiology 47:81–7CrossRef Google Scholar

Ware, J. E., Keller, S. D. (1996). Interpreting general health measures. In Quality of Life and Pharmacoeconomics in Clinical Trials, ed. B. Spilker, pp. 445–60. Philadelphia, PA: Lippincott-Raven

Guyatt, G., Osoba, D., Wu, A., Wyrwich, K., Norman, G. and the Clinical Significance Consensus Meeting Group (2002). Methods to explain the clinical significance of health status measures.Mayo Clinic Proceedings 77:371–83CrossRef Google Scholar PubMed

Cella, D., Hahn, E., Dineen, K. (2002). Meaningful change in cancer-specific quality of life scores: differences between improvement and worsening.Quality of Life Research 11:207–21CrossRef Google Scholar PubMed

Cohen, R. S., Mount, B. M. (2000). Living with cancer: “Good” days and “bad” days — what produces them?Cancer 89:1854–653.0.CO;2-C>CrossRef Google Scholar

Ringash, G. J., Redelmeier, D. A., O'Sullivan, B., Bezjak, A. A. (1999). Asymmetry of good and bad minimal important differences in quality of life for laryngeal cancer patients.Quality of Life Research 8:604 (abstract 214)Google Scholar

Rodrigues, G., Bezjak, A., Osoba, D.et al. (2000). Measuring patient perception of health-related quality-of-life changes using the Subjective Significance Questionnaire.Quality of Life Research 9:256 (abstract 1404)Google Scholar

Ross, M. (1989). Relation of implicit theories to the construction of personal histories.Psychological Reviews 96:341–7CrossRef Google Scholar

Norman, G. R., Stratford, P., Regehr, G. (1997). Methodological problems in the retrospective computation of responsiveness to change: the lesson of Cronbach.Journal of Clinical Epidemiology 50:869–79CrossRef Google Scholar PubMed

Sneeuw, K., Muller, M., Aaronson, N. (2000). Interpreting the significance of changes in EORTC QLQ-C30 and COOP/WONCA scores.Quality of Life Research 9:256 (abstract 1416)Google Scholar

Sprangers, M. A. G., Schwartz, C. E. (1999). Integrating response shift into health-related quality of life research: a theoretical model.Social Science and Medicine 48:1507–15CrossRef Google Scholar PubMed

Sprangers, M. A. G., Schwartz, C. E. (1999). The challenge of the response shift for quality-of-life based clinical oncology research (Editorial).Annals of Oncology 10:747–9CrossRef Google Scholar PubMed

Jansen, S. J. T., Stiggelbout, A. M., Nooij, E. M., Noordijk, E. M., Kievit, J. (2000). Response shift in quality of life measurement in early-stage breast cancer patients undergoing radiotherapy.Quality of Life Research 9:603–15CrossRef Google Scholar PubMed

Osoba, D., Brada, M., Prados, M. D., Yung, W. K. A., (2000). Effect of disease burden on health-related quality of life in patients with malignant gliomas.Neuro-Oncology 2: 221–8CrossRef Google Scholar PubMed

Hornbrook, this volume, Chapter 24

Cella, D., Bullinger, M., Scott, C., Gorkin, L., Barofsky, I., and the Clinical Significance Consensus Meeting Group. (2002). Group versus individual approaches to understanding the clinical significance of differences or changes in quality of life.Mayo Clinic Proceedings 77:384–92CrossRef Google Scholar PubMed

Sloan, J. A., Aaronson, N., Cappelleri, J. C., Fairclough, D. L., Varricchio, C., and the Clinical Significance Consensus Meeting Group. (2002). Assessing the clinical significance of single items relative to summated scores.Mayo Clinic Proceedings 77:479–87CrossRef Google Scholar PubMed

Frost, M. H., Bonomi, A. E., Ferrans, C. E., Wong, G. Y., Hays, R. D., and the Clinical Significance Consensus Meeting Group. (2002). Patient, clinician and population perspectives on determining the clinical significance of quality-of-life scores.Mayo Clinic Proceedings 77:488–94CrossRef Google Scholar PubMed

Symonds, T., Berzon, R., Marquis, P., Rummans, T., and the Clinical Significance Consensus Meeting Group (2002). The clinical significance of quality-of-life results: practical considerations for specific audiences.Mayo Clinic Proceedings 77:572–83CrossRef Google Scholar PubMed

Fayers, P., Machin, D. (2000). Quality of Life: Assessment, Analysis and Interpretation. Chichester: John Wiley & Sons

Sprangers, M. A. G., Moinpour, C., Moynihan, T. J., Patrick, D. L., Revicki, D. A., and the Clinical Significance Consensus Meeting Group. (2002). Assessing meaningful change over time in quality of life: a users' guide for clinicians.Mayo Clinic Proceedings 77:561–71CrossRef Google Scholar PubMed

Osoba, D. (1998). Guidelines for measuring health-related quality of life in clinical trials. In Quality of Life Assessment in Clinical Trials, ed. M. J. Staquet, R. D. Hays, P. M. Fayers, pp. 19–35. Oxford: Oxford University Press

Staquet, M., Berzon, R., Osoba, D., Machin, D. (1996). Guidelines for reporting results of quality of life assessments in clinical trials.Quality of Life Research 5:496–502CrossRef Google Scholar PubMed

Guyatt, G. H., Juniper, E. F., Walter, S. D., Griffith, L. E., Goldstein, R. S. (1998). Interpreting treatment effects in randomised trials.British Medical Journal 316:690–3CrossRef Google Scholar PubMed

Nunnally, J. C., Bernstein, I. H. (1994). Psychometric Theory (3rd Edition), pp. 264–5. New York, NY: McGraw-Hill, Inc

Revicki, D. A., Cella, D. F. (1997). Health status assessment for the twenty-first century: item response theory, item banking and computer adaptive testing.Quality of Life Research 6:595–600CrossRef Google Scholar PubMed

Revicki, D. A., Osoba, D., Fairclough, D.et al. (2000). Recommendation on health-related quality of life research to support labeling and promotional claims in the United States.Quality of Life Research 9:887–900CrossRef Google Scholar

Leidy, N. K., Revicki, D. A., Geneste, B. (1999). Recommendations for evaluating the validity of quality of life claims for labeling and promotion.Value in Health 2:113–27CrossRef Google Scholar PubMed

Ganz, P. A. (1995). Impact of quality of life outcomes on clinical practice.Oncology 9 (Suppl. 11):61–5Google Scholar PubMed

Osoba, D., Till, J. E., Pater, J. L., Young, J. R. (1995). Health-related quality of life: measurement and clinical application. A workshop report.Canadian Journal of Oncology 5:338–431Google Scholar PubMed