Health State Utility Value in Chronic Obstructive Pulmonary Disease (COPD); The Challenge of Heterogeneity: A Systematic Review and Meta-Analysis

References

• Bowling A, Measuring Disease: A Review of Disease Specific Quality of Life Measurement Scales Paperback, 2nd ed. Open University Press. Buckingham. Philadelphia 2001; p 6–7.
   Google Scholar
• FDA Center, U.S. Department of Health and Human Services for Drug Evaluation and Research Guidance for industry on patient-reported outcome measures: Use in medical product development to support labeling claims. Federal Register. 2009; 74: 65132–65133.
   Google Scholar
• Wilson AM, Browne P, Olive S, Clark A, Galey P, Dix E, et al. The effects of maintenance schedules following pulmonary rehabilitation in patients with chronic obstructive pulmonary disease: a randomised controlled trial. BMJ Open 2015; 5(3):e005921–e.
   PubMed Web of Science ®Google Scholar
• Briggs AH, Lozano-Ortega G, Spencer S, Bale G, Spencer MD, Burge PS. Estimating the cost-effectiveness of fluticasone propionate for treating chronic obstructive pulmonary disease in the presence of missing data. Value Health 2006; 9(4):227–235.
   PubMed Web of Science ®Google Scholar
• Sidhu MS, Daley A, Jordan R, Coventry PA, Heneghan C, Jowett S, et al. Patient self-management in primary care patients with mild COPD - protocol of a randomised controlled trial of telephone health coaching. BMC Pulm Med 2015; 15(1):16.
   PubMed Web of Science ®Google Scholar
• Thorn J, Tilling B, Lisspers K, Jorgensen L, Stenling A, Stratelis G. Improved prediction of COPD in at-risk patients using lung function pre-screening in primary care: a real-life study and cost-effectiveness analysis. Prim Care Respir J 2012; 21(2):159–166.
   PubMedGoogle Scholar
• Bremner KE, Chong CAKY, Tomlinson G, Alihhai SMH, Krahn MD. A review and meta-analysis of prostate cancer utilities. Med Decis Mak 2007; 27(3):288–298.
   PubMed Web of Science ®Google Scholar
• McLernon DJ, Dillon J, Donnan PT. Health-state utilities in liver disease: A systematic review. Med Decis Mak 2008; 28(4):582–592.
   PubMed Web of Science ®Google Scholar
• Peasgood T, Brazier J. Is meta-analysis for utility values appropriate given the potential impact different elicitation methods have on values? Pharmacoeconomics 2015; doi: 10.1007/s40273-015-0310-y
   Google Scholar
• Dolan P. Modeling valuations for EuroQol health states. Med Care 1997; 35(11):1095–1108.
   PubMed Web of Science ®Google Scholar
• Tsuchiya A, Ikeda S, Ikegami N, Nishimura S, Sakai I, Fukuda T, et al. Estimating an EQ-5D population value set: the case of Japan. Health Econ 2002; 11(4):341–353.
   PubMed Web of Science ®Google Scholar
• Walters SJ, Brazier JE. Comparison of the minimally important difference for two health state utility measures: EQ-5D and SF-6D. Qual Life Res 2005; 14(6):1523–1532.
   PubMed Web of Science ®Google Scholar
• Lung TWC, Hayes AJ, Hayen A, Farmer A, Clarke PM. A meta-analysis of health state valuations for people with diabetes: explaining the variation across methods and implications for economic evaluation. Qual Life Res 2011; 20:1669–1678.
   PubMed Web of Science ®Google Scholar
• Sturza J. A review and meta-analysis of utility values for lung cancer. Med Decis Mak 2010; 30:685.
   PubMed Web of Science ®Google Scholar
• Djalalov S, Rabeneck L, Tomlinson G, Bremner KE, Hilsden R, Hoch JS. A review and meta-analysis of colorectal cancer utilities. Med Decis Mak 2014; 34(6):809–818.
   PubMed Web of Science ®Google Scholar
• Tengs TO, Lin TH. A meta-analysis of utility estimates for HIV/AIDS. Med Decis Mak 2002; 22(6):475–481.
   PubMed Web of Science ®Google Scholar
• Wyld M, Morton RL, Hayen A, Howard K, Webster AC. A Systematic Review and Meta-Analysis of Utility-Based Quality of Life in Chronic Kidney Disease Treatments. PLoS Med 2012; 9(9).
   PubMed Web of Science ®Google Scholar
• Doth AH, Hansson PT, Jensen MP, Taylor RS. The burden of neuropathic pain: A systematic review and meta-analysis of health utilities. Pain 2010; 149(2):338–344.
   PubMed Web of Science ®Google Scholar
• Si L, Winzenberg TM, de Graaff B, Palmer AJ. A systematic review and meta-analysis of utility-based quality of life for osteoporosis-related conditions. Osteoporos Int 2014; 25(8):1987–1997.
   PubMed Web of Science ®Google Scholar
• Fletcher MJ, Upton J, Taylor-Fishwick J, Buist SA, Jenkins C, Hutton J, et al. COPD uncovered: an international survey on the impact of chronic obstructive pulmonary disease COPD on a working age population. BMC Public Health 2011; 11.
   PubMed Web of Science ®Google Scholar
• Rutten-van Molken MPMH, Hoogendoorn M, Lamers LM. Holistic preferences for 1-year health profiles describing fluctuations in health the case of chronic obstructive pulmonary disease. Pharmacoeconomics 2009; 27(6):465–477.
   PubMed Web of Science ®Google Scholar
• Stroup DF, Berlin JA, Morton SC, Olkin I, Williamson GD, Rennie D, et al. Meta-analysis of observational studies in epidemiology—A proposal for reporting. JAMA 2000; 283(15):2008–2012.
   PubMed Web of Science ®Google Scholar
• Gleser LJ, Olkin I. Models for estimating the number of unpublished studies. Stat Med 1996; 15(23):2493–2507.
   PubMed Web of Science ®Google Scholar
• Harris RJ, Bradburn MJ, Deeks JJ, Harbord RM, Altman DG, Sterne JAC. metan: fixed- and random-effects meta-analysis. Stata J 2008; 8(1):3–28.
   Web of Science ®Google Scholar
• Palmer TM, Sterne JAC (eds.). Meta-Analysis in stata: an updated collection from the stata journal, second edition. College Station, Texas: Stata Press. 2016.
   Google Scholar
• Sterne JAC, Harbord RM. Funnel plots in meta-analysis. Stata J 2004; 4(2): 127–141.
   Google Scholar
• Asukai, Y, Baldwin M, Mungapen, L. Utility values for COPD patients based on the EQ-5D questionnaire from three Indacaterol phase III studies. Thorax 2012; 67: A100–A101.
   Google Scholar
• Calverley PMA, Rabe KF, Goehring U-M, Kristiansen S, Fabbri LM, Martinez FJ, et al. Roflumilast in symptomatic chronic obstructive pulmonary disease: two randomised clinical trials. Lancet 2009; 374(9691):685–694.
   Google Scholar
• Ringbaek T, Brondurn E, Martinez G, Lange P. EuroQoL in assessment of the effect of pulmonary rehabilitation COPD patients. Respir Med 2008; 102(11):1563–1567.
   Google Scholar
• Wu M, Zhao Q, Chen Y, Fu C, Xu B. Quality of life and its association with direct medical costs for COPD in urban China. Health Qual Life Outcomes 2015; 13.
   PubMed Web of Science ®Google Scholar
• Wilson AM, Browne P, Olive S, Clark A, Galey P, Dix E, et al. The effects of maintenance schedules following pulmonary rehabilitation in patients with chronic obstructive pulmonary disease: a randomised controlled trial. BMJ Open 2015; 5(3):e005921–e.
   PubMed Web of Science ®Google Scholar
• Sundh J, Johansson G, Larsson K, Linden A, Lofdahl C-G, Janson C, et al. Comorbidity and health-related quality of life in patients with severe chronic obstructive pulmonary disease attending Swedish secondary care units. Int J Chron Obstruct Pulmon Dis 2015; 10:173–183.
   PubMed Web of Science ®Google Scholar
• Stoddart A, van der Pol M, Pinnock H, Hanley J, McCloughan L, Todd A, et al. Telemonitoring for chronic obstructive pulmonary disease: a cost and cost-utility analysis of a randomised controlled trial. J Telemed Telecare 2015; 21(2):108–118.
   PubMed Web of Science ®Google Scholar
• McDowell JE, McClean S, FitzGibbon F, Tate S. A randomised clinical trial of the effectiveness of home-based health care with telemonitoring in patients with COPD. J Telemed Telecare 2015; 21(2):80–87.
   PubMed Web of Science ®Google Scholar
• Donohue JF, Worsley S, Zhu C-Q, Hardaker L, Church A. Improvements in lung function with umeclidinium/vilanterol versus fluticasone propionate/salmeterol in patients with moderate-to-severe COPD and infrequent exacerbations. Respir Med 2015; 109(7):870–881.
   PubMed Web of Science ®Google Scholar
• Lin F-J, Pickard AS, Krishnan JA, Joo MJ, Au DH, Carson SS, et al. Measuring health-related quality of life in chronic obstructive pulmonary disease: properties of the EQ-5D-5L and PROMIS-43 short form. BMC Med Res Methodol 2014; 14.
   PubMed Web of Science ®Google Scholar
• Ferreira LN, Ferreira PL, Pereira LN. Comparing the performance of the SF-6D and the EQ-5D in Different Patient Groups. Acta Med Port 2014; 27(2):236–245.
   PubMed Web of Science ®Google Scholar
• Chen J, Wong CKH, McGhee SM, Pang PKP, Yu W-C. A comparison between the EQ-5D and the SF-6D in patients with chronic obstructive pulmonary disease (COPD). PLoS One 2014; 9(11).
   Web of Science ®Google Scholar
• Gillespie P, O'Shea E, Casey D, Murphy K, Devane D, Cooney A, et al. The cost-effectiveness of a structured education pulmonary rehabilitation programme for chronic obstructive pulmonary disease in primary care: the PRINCE cluster randomised trial. BMJ Open 2013; 3(11).
   Web of Science ®Google Scholar
• Browne P, Olive S, Staunton L, Clark A, Wilson E, Galey P, Wilson AM. The Effects of maintenance schedules following pulmonary rehabilitation in patients with chronic obstructive pulmonary disease. Thorax 2013; 68:A16.
   Web of Science ®Google Scholar
• Kruis AL, Boland MRS, Schoonvelde CH, Assendelft WJJ, Rutten-van Moelken MPMH, Gussekloo J, et al. RECODE: Design and baseline results of a cluster randomized trial on cost-effectiveness of integrated COPD management in primary care. BMC Pulm Med 2013; 13.
   PubMed Web of Science ®Google Scholar
• Taylor SJC, Sohanpal R, Bremner SA, Devine A, McDaid D, Fernandez J-L, et al. Self-management support for moderate-to-severe chronic obstructive pulmonary disease: a pilot randomised controlled trial. Br J Gen Pract 2012; 62(603):e687–695.
   PubMed Web of Science ®Google Scholar
• Garcia-Polo C, Alcazar-Navarrete B, Alberto Ruiz-Iturriaga L, Herrejon A, Antonio Ros-Lucas J, Garcia-Sidro P, et al. Factors associated with high healthcare resource utilisation among COPD patients. Respir Med 2012; 106(12):1734–1742.
   PubMed Web of Science ®Google Scholar
• Naberan K, Azpeitia A, Cantoni J, Miravitlles M. Impairment of quality of life in women with chronic obstructive pulmonary disease. Respir Med 2012; 106(3):367–373.
   PubMed Web of Science ®Google Scholar
• Egan C, Deering BM, Blake C, Fullen BM, McCormack NM, Spruit MA, et al. Short term and long term effects of pulmonary rehabilitation on physical activity in COPD. Respir Med 2012; 106(12):1671–1679.
   PubMed Web of Science ®Google Scholar
• Starkie HJ, Briggs AH, Chambers MG, Jones P. Predicting EQ-5D values using the SGRQ. Value Health 2011; 14(2):354–360.
   PubMed Web of Science ®Google Scholar
• Janssen DJA, Franssen FME, Wouters EFM, Schols JMGA, Spruit MA. Impaired health status and care dependency in patients with advanced COPD or chronic heart failure. Qual Life Res 2011; 20(10):1679–1688.
   PubMed Web of Science ®Google Scholar
• Khdour MR, Agus AM, Kidney JC, Smyth BM, Elnay JC, Crealey GE. Cost-utility analysis of a pharmacy-led self-management programme for patients with COPD. Int J Clin Pharm 2011; 33(4):665–673.
   PubMed Web of Science ®Google Scholar
• Pickard AS, Yang Y, Lee TA. Comparison of health-related quality of life measures in chronic obstructive pulmonary disease. Health Qual Life Outcomes 2011; 9.
   PubMed Web of Science ®Google Scholar
• Agh T, Inotai A, Meszaros A. factors associated with medication adherence in patients with chronic obstructive pulmonary disease. Respiration 2011; 82(4):328–334.
   PubMed Web of Science ®Google Scholar
• Heyworth ITM, Hazell ML, Linehan MF, Frank TL. How do common chronic conditions affect health-related quality of life? Br J Gen Pract 2009; 59(568):e353–358.
   PubMed Web of Science ®Google Scholar
• Miravitlles M, Naberan K, Cantoni J, Azpeitia A. Socioeconomic status and health-related quality of life of patients with chronic obstructive pulmonary disease. Respiration 2011; 82(5):402–408.
   PubMed Web of Science ®Google Scholar
• Skoupa J, Blahova M, Kasak V, Cerna V, Maly M. The Czech burden study: burden and quality of life in chronic obstructive pulmonary disease exacerbation. Value Health. 2009; 12(7): A300--A300.
   Google Scholar
• Stellefson M, Chaney BH, Chaney JD. Using exploratory focus groups to inform the development of targeted COPD self-management education DVDs for rural patients. Int J Telemed Appl 2010; 2010:450418.
   PubMedGoogle Scholar
• Punekar YS, Rodriguez-Roisin R, Sculpher M, Jones P, Spencer M. Implications of chronic obstructive pulmonary disease (COPD) on patients' health status: A western view. Respir Med 2007; 101(3):661–669.
   PubMed Web of Science ®Google Scholar
• Rutten-Van Molken MPMH, Oostenbrink JB, Tashkin DP, Burkhart D, Monz BU. Does quality of life of COPD patients as measured by the generic EuroQol five-dimension questionnaire differentiate between COPD severity stages? Chest 2006; 130(4):1117–1128.
   PubMed Web of Science ®Google Scholar
• Decramer M, Rutten-van Molken M, Dekhuijzen PNR, Troosters T, van Herwaarden C, Pellegrino R, et al. Effects of N-acetylcysteine on outcomes in chronic obstructive pulmonary disease (Bronchitis Randomized on NAC Cost-Utility Study, BRONCUS): a randomised placebo-controlled trial. Lancet 2005; 365(9470):1552–1560.
   PubMed Web of Science ®Google Scholar
• Brazier J, Roberts J, Tsuchiya A, Busschbach J. A comparison of the EQ-5D and SF-6D across seven patient groups. Health Econ 2004; 13(9):873–884.
   PubMed Web of Science ®Google Scholar
• Monninkhof E, van der Valk P, Schermer T, van der Palen J, Van Herwaarden C, Zielhuis G. Economic evaluation of a comprehensive self-management programme in patients with moderate to severe chronic obstructive pulmonary disease. Chron Respir Dis 2004; 1(1):7–16.
   PubMedGoogle Scholar
• Kim S-H, Oh YM, Jo M-W. Health-related quality of life in chronic obstructive pulmonary disease patients in Korea. Health Qual Life Outcomes 2014;12.
   PubMed Web of Science ®Google Scholar
• Kim ES, Lee BJ, Lee GW, Jung AR, Hwang HS. Health status in adult patients with COPD in Korea. Value Health 2014; 17(7):A779–A780.
   PubMed Web of Science ®Google Scholar
• Jodar-Sanchez F, Ortega F, Parra C, Gomez-Suarez C, Bonachela P, Leal S, et al. Cost-utility analysis of a telehealth programme for patients with severe chronic obstructive pulmonary disease treated with long-term oxygen therapy. J Telemed Telecare. 2014;20(6):307–16.
   PubMed Web of Science ®Google Scholar
• Samyshkin Y, Schlunegger M, Haefliger S, Ledderhose S, Radford M. Cost-effectiveness of roflumilast in combination with bronchodilator therapies in patients with severe and very severe COPD in Switzerland. Int J Chron Obstruct Pulmon Dis 2013; 8:79–87.
   PubMed Web of Science ®Google Scholar
• Solem CT, Sun SX, Sudharshan L, Macahilig C, Katyal M, Gao X. Impact of severe and very severe chronic obstructive pulmonary disease (COPD) on health-related quality of life (HRQOL) and work productivity: results of a nationally representative patient survey and chart review of recently exacerbating patients. Value Health 2013; 16(3):A240.
   Web of Science ®Google Scholar
• Menn P, Weber N, Holle R. Health-related quality of life in patients with severe COPD hospitalized for exacerbations—comparing EQ-5D, SF-12 and SGRQ. Health Qual Life Outcomes 2010; 8:39.
   PubMed Web of Science ®Google Scholar
• Molken MPMHR-v, Oostenbrink JB, Miravitlles M, Monz BU. Modelling the 5-year cost effectiveness of tiotropium, salmeterol and ipratropium for the treatment of chronic obstructive pulmonary disease in Spain. Eur J Health Econ 2007; 8(2):123–135.
   PubMed Web of Science ®Google Scholar
• Stahl E, Jansson S-A, Jonsson A-C, Svensson K, Lundback B, Andersson F. Health-related quality of life, utility, and productivity outcomes instruments: ease of completion by subjects with COPD. Health Qual Life Outcomes 2003; 1:18.
   PubMedGoogle Scholar
• Spencer M, Briggs AH, Grossman RF, Rance L. Development of an economic model to assess the cost effectiveness of treatment interventions for chronic obstructive pulmonary disease. PharmacoEconomics 2005; 23(6):619–637.
   PubMed Web of Science ®Google Scholar
• Borg S, Ericsson A, Wedzicha J, Gulsvik A, Lundback B, Donaldson GC, et al. A computer simulation model of the natural history and economic impact of chronic obstructive pulmonary disease. Value Health 2004; 7(2):153–167.
   PubMed Web of Science ®Google Scholar
• O'Reilly JF, Williams AE, Rice L. Health status impairment and costs associated with COPD exacerbation managed in hospital. Int J Clin Pract 2007; 61(7):1112–1120.
   PubMed Web of Science ®Google Scholar
• Koo H-K, Park J-H, Park HK, Jung H, Lee S-S. Conflicting role of sarcopenia and obesity in male patients with chronic obstructive pulmonary disease: Korean National Health and Nutrition Examination Survey. PLoS One 2014; 9(10).
   Web of Science ®Google Scholar
• Global Strategy for the Diagnosis, Management and Prevention of Chronic Obstructive Pulmonary Disease. Updated January 2014. Available from: http://www.goldcopd.org/guidelines-global-strategy-for-diagnosis-management.html. (Accessed December 2, 2015).
   Google Scholar
• Macaskill P, Walter SD, Irwig L. A comparison of methods to detect publication bias in meta-analysis. Stat Med 2011; 20(4):641–654.
   Google Scholar
• Luo N, Johnson JA, Shaw JW, Feeny D, Coons SJ. Self-reported health status of the general adult US population as assessed by the EQ-5D and Health Utilities Index. Med Care 2005; 43(11):1078–1086.
   Google Scholar
• Johnson JA and Pickard AS. Comparison of the EQ-5D and SF-12 health surveys in a general population survey in Alberta, Canada. Med Care 2000; 38(1):115–121.
   PubMed Web of Science ®Google Scholar
• Clemens S, Begum N, Harper C, Whitty JA, Scuffham PA. A comparison of EQ-5D-3L population norms in Queensland, Australia, estimated using utility value sets from Australia, the UK and USA. Qual Life Res 2014; 23(8):2375–2381.
   PubMed Web of Science ®Google Scholar
• Richardson J, Iezzi A, Khan MA. Why do multi-attribute utility instruments produce different utilities: the relative importance of the descriptive systems, scale and 'micro-utility' effects? Qual Life Res 2015; 24(8):2045–2053.
   PubMed Web of Science ®Google Scholar
• Puhan MA, Soesilo I, Guyatt GH, Schuenemann HJ. Combining scores from different patient reported outcome measures in meta-analyses: when is it justified? Health Qual Life Outcomes. 2006; 4:94
   Google Scholar
• Petrillo J, van Nooten F, Jones P, Rutten-van Molken M. Utility estimation in chronic obstructive pulmonary disease A preference for change? Pharmacoeconomics 2011; 29(11):917–932.
   PubMed Web of Science ®Google Scholar
• Szende A, Leidy NK, Stahl E, Svensson K. Estimating health utilities in patients with asthma and COPD: evidence on the performance of EQ-5D and SF-6D. Qual Life Res 2009; 18(2):267–272.
   Google Scholar
• Guyatt GH, King DR, Feeny DH, Stubbing D, Goldstein RS. Generic and specific measurement of health-related quality of life in a clinical trial of respiratory rehabilitation. J Clin Epidemiol 1999; 52(3):187–192.
   Google Scholar
• Hesselink AE, van der Windt DAWM, Penninx BWJH, Wijnhoven HAH, Twisk JWR, Bouter LM, et al. What predicts change in pulmonary function and quality of life in asthma or COPD? J Asthma 2006; 43(7):513–519.
   PubMed Web of Science ®Google Scholar
• Tsiligianni I, Kocks J, Tzanakis N, Siafakas N, van der Molen T. Factors that influence disease-specific quality of life or health status in patients with COPD: a systematic review and meta-analysis of Pearson correlations. Prim Care Respir J 2011; 20(3):257–268.
   PubMedGoogle Scholar
• Verhage TL, Heijdra YF, Molema J, Daudey L, Dekhuijzen PNR, Vercoulen JH. Adequate patient characterization in COPD: Reasons to go beyond GOLD classification. Open Respir Med J 2009; 3:1–9.
   PubMedGoogle Scholar
• Wijnhoven HAH, Kriegsman DMW, Hesselink AE, Penninx B, de Haan M. Determinants of different dimensions of disease severity in asthma and COPD— Pulmonary function and health-related quality of life. Chest 2001; 119(4):1034–1042.
   PubMed Web of Science ®Google Scholar
• Einarson TR, Bereza BG, Nielsen TA, Hemels MEH. Utilities for asthma and COPD according to category of severity: a comprehensive literature review. J Med Econ 2015; 18(7):550–563.
   PubMed Web of Science ®Google Scholar
• Pickard AS, Wilke C, Jung E, Patel S, Stavem K, Lee TA. Use of a preference-based measure of health (EQ-5D) in COPD and asthma. Respir Med 2008; 102(4):519–536.
   PubMed Web of Science ®Google Scholar
• Torrance GW, Feeny D, Furlong W. Visual analogue scales: Do they have a role in the measurement of preferences for health states? Med Decis Mak 2001; 21(4):329–334.
   PubMed Web of Science ®Google Scholar
• Ruchlin HS, Insinga RP. A review of health-utility data for osteoarthritis implications for clinical trial-based evaluation. Pharmacoeconomics 2008; 26(11): 925–935.
   PubMed Web of Science ®Google Scholar
• Boland MRS, Tsiachristas A, Kruis AL, Chavannes NH, Rutten-van Molken MPMH. The health economic impact of disease management programs for COPD: a systematic literature review and meta-analysis. BMC Pulm Med 2013; 13.
   PubMed Web of Science ®Google Scholar
• Srivastava K, Thakur D, Sharma S, Punekar YS. Systematic review of humanistic and economic burden of symptomatic chronic obstructive pulmonary disease. Pharmacoeconomics 2015; 33(5):467–488.
   Google Scholar
• Miravitlles M, Izquierdo I, Herrejon A, Vicente Torres J, Baro E, Borja J, et al. COPD severity score as a predictor of failure in exacerbations of COPD. The ESFERA study. Respir Med 2011;105(5):740–747.
   PubMed Web of Science ®Google Scholar
• Miller J, Edwards LD, Agusti A, Bakke P, Calverley PMA, Celli B, et al. Comorbidity, systemic inflammation and outcomes in the ECLIPSE cohort. Respir Med 2013; 107(9):1376–1384.
   PubMed Web of Science ®Google Scholar
• Frei A, Muggensturm P, Putcha N, Siebeling L, Zoller M, Boyd CM, et al. Five comorbidities reflected the health status in patients with chronic obstructive pulmonary disease: the newly developed COMCOLD index. J Clin Epidemiol 2014; 67(8):904–911.
   PubMed Web of Science ®Google Scholar
• Fortin M, Dionne J, Pinbo GV, Gignac J, Almirall J, Lapointe L. Randomized controlled trials: Do they have external validity for patients with multiple comorbidities? Ann Fam Med 2006; 4(2):104–108.
   PubMed Web of Science ®Google Scholar