Intraclass correlation coefficients for cluster randomized trials in care pathways and usual care: hospital treatment for heart failure

Seval Kul, Kris Vanhaecht, Massimiliano Panella, Seval Kul, Kris Vanhaecht, Massimiliano Panella

Abstract

Background: Cluster randomized trials are increasingly being used in healthcare evaluation to show the effectiveness of a specific intervention. Care pathways (CPs) are becoming a popular tool to improve the quality of health-care services provided to heart failure patients. In order to perform a well-designed cluster randomized trial to demonstrate the effectiveness of Usual care (UC) and CP in heart failure treatment, the intraclass correlation coefficient (ICC) should be available before conducting a trial to estimate the required sample size. This study reports ICCs for both demographical and outcome variables from cluster randomized trials of heart failure patients in UC and care pathways.

Methods: To calculate the degree of within-cluster dependence, the ICC and associated 95% confidence interval were calculated by a method based on analysis of variance. All analyses were performed in R software version 2.15.1.

Results: ICCs for baseline characteristics ranged from 0.025 to 0.058. The median value and interquartile range was 0.043 [0.026-0.052] for ICCs of baseline characteristics. Among baseline characteristics, the highest ICCs were found for admission by referral or admission from home (ICC = 0.058) and the disease severity at admission (ICC = 0.046). Corresponding ICCs for appropriateness of the stay, length of stay and hospitalization cost were 0.069, 0.063, and 0.001 in CP group and 0.203, 0.020, 0.046 for usual care, respectively.

Conclusion: Reported values of ICCs from present care pathway trial and UC results for some common outcomes will be helpful for estimating sample size in future clustered randomized heart failure trials, in particular for the evaluation of care pathways.

References

    1. Ukoumunne OC, Gulliford MC, Chinn S, Sterne JAC, Burney PGJ, Donner A. Evaluation of health interventions at area and organization level. BMJ. 1999;14:376–379. doi: 10.1136/bmj.319.7206.376.
    1. Donner A, Klar N. Cluster randomisation trials in epidemiology: theory and application. J Stat Plan Interference. 1994;14:37–56. doi: 10.1016/0378-3758(94)90188-0.
    1. Donner A. Sample size requirements for strafied cluster randomisation designs. Stat Med. 1992;14(6):743–750. doi: 10.1002/sim.4780110605.
    1. Donner A, Birkett N, Buck C. Randomization by cluster sample size requirements and analysis. Am J Epidemiol. 1981;14:906–914.
    1. Mcghee G, Murphy E. Research on reducing hospitalizations in patients with chronic heart failure. Home Healthc Nurse. 2010;14:335–340. doi: 10.1097/NHH.0b013e3181df5e30.
    1. Cowie MR, Fox KF, Wood DA, Metcalfe C, Thompson SG, Coats AJ, Poole-Wilson PA, Sutton GC. Hospitalization of patients with heart failure. A population-based study. Eur Hearth J. 2002;14:877–885.
    1. American Heart Association. Heart Disease and Stroke Statistics: 2010 Update. A report from the American heart association statistics committee and stroke statistics. doi:10.1161/CIRCULATIONAHA.109.192667 Published online ahead of print 17 December 2009.
    1. Mariotto AB, Yabroff KR, Shao Y, Feuer EJ, Brow ML. Projections of the cost of cancer care in the United States 2010–2020. J Nat Cancer Inst. 2011;14:117–128. doi: 10.1093/jnci/djq495.
    1. Vanhaecht K. The impact of care pathways on the organization of care processes. Acco, Leuven. 2007. p. 157.
    1. Campbell H, Hotchkiss R, Bradshaw N, Porteous M. Integrated care pathways. BMJ. 1998;14:133–137. doi: 10.1136/bmj.316.7125.133.
    1. Panella M, Marchisio S, Di Stanislao F. Reducing clinical variations with clinical pathways: do pathways work? Int J Qual Health Care. 2003;14:509–521. doi: 10.1093/intqhc/mzg057.
    1. Azad N, Molnar F, Byszewski A. Lessons learned from a multidisciplinary heart failure clinic for older women: a randomised controlled trial. Age Ageing. 2008;14:282–287. doi: 10.1093/ageing/afn013.
    1. Panella M, Marchisio S, Demarchi ML, Manzoli L, Stanislao FD. Reduced in-hospital mortality for heart failure with clinical pathways: the results of a cluster randomised controlled trial. Qual Saf Health Care. 2009;14:369–373. doi: 10.1136/qshc.2008.026559.
    1. Rauh RA, Schwabauer RN, Enger EL, Moran JF. A Community hospital-based congestive hearth failure program: Impact on length of stay, admission and readmission rates and cost. Am J Manag Care. 1999;14:37–43.
    1. Philbin E, Thomas AR, Lindenmuth NW, Ulrich K, McCall M, Jenkins PL. The results of a randomized trial of quality improvement intervention in the care of patients with heart failure. AM J Med. 2000;14:443–449. doi: 10.1016/S0002-9343(00)00544-1.
    1. Panella M, Vanhaecht K. Is there still need for confusion about pathways? Int J Care Pathways. 2010;14:1–3. doi: 10.1258/jicp.2010.010008.
    1. Murray DM, Catellier DJ, Hannan PJ, Treuth MS, Stevens J, Schmitz KH, Rice JC, Conway TR. School level intraclass correlation for physical activity in adolescent girls. Med Sci Sports Exerc. 2004;14:876–882.
    1. Hannan PJ, Murray DM, Jacobs DR, McGovern PG. Parameters to aid in the design and analysis of community trials: intraclass correlation from the Minesota heart health program. Epidemiology. 1994;14:88–95. doi: 10.1097/00001648-199401000-00013.
    1. Cosby R, Howard M, Kaczorowski J, Willian AR, Sellors JW. Randomizing patients by family practice: sample size estimation, intracluster correlation and data analysis. Fam Pract. 2003;14:77–82. doi: 10.1093/fampra/20.1.77.
    1. Adams G, Gulliford MC, Ukoumunne OC, Eldridge S, Chinn S, Camphell MJ. Patterns of intra-cluster correlation from primary care research to inform study design and analysis. J Clin Epidemiol. 2004;14:785–794. doi: 10.1016/j.jclinepi.2003.12.013.
    1. Elley CR, Kerse N, Chondros P, Robinson E. Intraclass correlation coefficient from three cluster randomised controlled trials in primary and residential health care. Aust N Z J Public Health. 2005;14:461–467. doi: 10.1111/j.1467-842X.2005.tb00227.x.
    1. Parker DR, Evangelou E, Eaton CB. Intraclass correlation coefficients for cluster randomized trials in primary care: the cholesterol education and research trial [CEART] Contemp Clin Trials. 2005;14:260–267. doi: 10.1016/j.cct.2005.01.002.
    1. Panella M, Marchisio S, Gardini A, Di Stanislao F. A cluster randomized controlled trial of a clinical pathway for hospital treatment of heart failure: study design and population. BMC Health Serv Res. 2007;14:179–185. doi: 10.1186/1472-6963-7-179.
    1. Donner A, Klar N. Design and analysis of cluster randomization trials in health research. London: Arnold; 2000.
    1. Smith CAB. On the estimation of intraclass correlation. Ann Hum Genet. 1956;14:363–373.
    1. Golstein H, Browne H, Rasbash J. Partitioning variation in multilevel models. Underst Stat. 2002;14(4):223–231. doi: 10.1207/S15328031US0104_02.
    1. Ukoumunne OC. A comparison of confidence interval methods for the intraclass correlation coefficient in cluster randomized trials. Stat Med. 2002;14:3757–3774. doi: 10.1002/sim.1330.
    1. Kerryand SM, Bland JM. Statistics notes: the intracluster correlation coefficient in cluster randomisation. BMJ. 1998;14:1455–1460.
    1. Ukoumunne OC, Gulliford MC, Chinn S, Sterne JAC, Burney PGJ. Methods for evaluating area-wide and organisation-based interventions in health and health care: a systematic review. Health Technol Assess. 1999;14(5):iii–92.
    1. Murray DM, Bliststein JL. Methods to reduce the impact of intraclass correlation in group-randomized trials. Eval Rev. 2003;14:79–103. doi: 10.1177/0193841X02239019.
    1. Killip S, Mahfounf Z, Pearche K. What is an intraclass correlation coefficient? Crucial concepts for primary care researchers. Ann Fam Med. 2004;14:204–208. doi: 10.1370/afm.141.
    1. Gulliford MC, Ukoumunne OC, Chinn S. Components of variance and intraclass correlations for the design of community-based surveys and intervention studies: data from the health survey for England 1994. Am J Epidemiol. 1999;14:876–883. doi: 10.1093/oxfordjournals.aje.a009904.
    1. Smeeth L, Ng S. Intraclass correlation coefficients for cluster randomized trials in primary care: data from MRC trial of the assessment and management of older people in community. Control Clin trials. 2002;14:409–421. doi: 10.1016/S0197-2456(02)00208-8.
    1. Murray DM, Rooney BL, Hannan PJ, Peterson AV, Ary DV, Biglan A, Botvin GJ, Evans RI, Flay BR, Futterman R. et al.Intraclass correlation among common measures of adolescent smoking. Am J Epidemiol. 1992;14:1038–1050.
    1. Lowrie R, Mair FS, Greenlaw N, Forsyth P, Jhund PS, McConnachie A, Rae B, McMurray JJ. Heart Failure Optimal Outcomes from Pharmacy Study (HOOPS) Investigators. Pharmacist intervention in primary care to improve outcomes in patients with left ventricular systolic dysfunction. Eur Heart J. 2012;14(3):314–324. doi: 10.1093/eurheartj/ehr433.
    1. Lowrie R, Mair FS, Greenlaw N, Forsyth P, McConnachie A, Richardson J, Khan N, Morrison D, Messow CM, Rae B, McMurray JJ. The Heart failure and Optimal Outcomes from Pharmacy Study (HOOPS): rationale, design, and baseline characteristics. Eur J Heart Fail. 2011;14(8):917–924. doi: 10.1093/eurjhf/hfr083.
    1. Campbell MK, Grimshaw JM, Elbourne DR. Intracluster correlation coefficients in cluster randomized trials: empirical insights into how should they be reported. BMC Med Res Methodol. 2004;14:4–9.
    1. Campbell M, Grimshaw J, Steen N. Sample size calculations for cluster randomised trials. Changing professional practice in Europe group [EU BIOMED II concerted action] J Health Serv Res Policy. 2000;14(1):12–16.
    1. West BT, Welch KB, Galecki AT. Linear mixed models: a practical guide using statistical software. Chapman & Hall: Boca Raton; 2007.
    1. Yelland LN, Salter AB, Ryan P, Laurence CO. Adjusted intraclass correlation coefficients for binary data: methods and estimates from a cluster-randomized trial in primary care. Clin Trials. 2011;14:48–58. doi: 10.1177/1740774510392256.
    1. Zou G, Donner A. Confidence interval estimation of the intraclass correlation coefficient for binary data outcome data. Biometrics. 2004;14:807–811. doi: 10.1111/j.0006-341X.2004.00232.x.
    1. Donner A, Koval J. Design consideration in the estimation of the intraclass correlation. Ann Hum Genet. 1982;14:271–277. doi: 10.1111/j.1469-1809.1982.tb00718.x.
    1. Turner RM, Omar RZ, Thompson SG. Bayesian methods of analysis for cluster randomized trials with binary outcome data. Stat Med. 2001;14:453–472. doi: 10.1002/1097-0258(20010215)20:3<453::AID-SIM803>;2-L.
    1. Campbell MK, Thomson S, Ramsay CR, MacLennan GS, Grimshaw JM. Sample size calculator for cluster randomised trials. Comput Biol Med. 2004;14(2):113–125. doi: 10.1016/S0010-4825(03)00039-8.
    1. Eldridge S, Kerry S, Ashby D. Sample size for cluster randomized trials: effect of coefficient of variation of cluster size and analysis method. Am J Epidemiol. 2006;14:1292–1300.
    1. Hemming K, Girling AJ, Sitch AJ, Marsh J, Lilford RJ. Sample size calculations for cluster randomised controlled trials with a fixed number of clusters. BMC Med Res Methodol. 2011;14(11):102–106.
    1. Rotondi M, Donner A. Sample size estimation in cluster randomized trials: an evidence-based perspective. Comput Stat Data Anal. 2012;14(5):1174–1187. doi: 10.1016/j.csda.2010.12.010.
    1. Rotondi M. CRT size: sample size estimation for cluster randomized trials. 2012. .

Source: PubMed

赞助者和合作者

医疗条件

药物干预

3
订阅