Health and Quality of Life Outcomes BioMed Central Research Open Access Internal consistency reliability is a poor predictor of responsiveness Milo A Puhan*1, Dianne Bryant2, Gordon H Guyatt2,3, Diane Heels-Ansdell2 and Holger J Schünemann2 Address: 1Horten Centre, University Hospital, Postfach Nord, 8091 Zurich, Switzerland, 2Department of Clinical Epidemiology and Biostatistics, McMaster University, 1200 Main St. W., Health Sciences Centre, Room 2C12, Hamilton, Ontario, L8N 3Z5 Canada and 3Department of Medicine, McMaster University, Health Sciences Centre, Hamilton, Ontario, L8N 3Z5 Canada Email: Milo A Puhan* - ; Dianne Bryant - jackowdm@; Gordon H Guyatt - guyatt@; Diane Heels-Ansdell - ansdell@; Holger J Schünemann - hjs@ * Corresponding. | BioMed Central Health and Quality of Life Outcomes Research Open Access Internal consistency reliability is a poor predictor of responsiveness Milo A Puhan 1 Dianne Bryant2 Gordon H Guyatt2 3 Diane Heels-Ansdell2 and Holger J Schunemann2 Address 1Horten Centre University Hospital Postfach Nord 8091 Zurich Switzerland 2Department of Clinical Epidemiology and Biostatistics McMaster University 1200 Main St. W. Health Sciences Centre Room 2C12 Hamilton Ontario L8N 3Z5 Canada and 3Department of Medicine McMaster University Health Sciences Centre Hamilton Ontario L8N 3Z5 Canada Email Milo A Puhan - Dianne Bryant - jackowdm@ Gordon H Guyatt - guyatt@ Diane Heels-Ansdell - ansdell@ Holger J Schunemann - hjs@ Corresponding author Published 09 May 2005 Received 07 April 2005 Health and Quality of Life Outcomes 2005 3 33 doi 1477-7525-3-33 Accepted 09 May 2005 This article is available from http content 3 1 33 2005 Puhan et al licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License http licenses by which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. Abstract Background Whether responsiveness represents a measurement property of health-related quality of life HRQL instruments that is distinct from reliability and validity is an issue of debate. We addressed the claims of a recent study which suggested that investigators could rely on internal consistency to reflect instrument responsiveness. Methods 516 patients with chronic obstructive pulmonary disease or knee injury participating in four longitudinal studies completed generic and disease-specific HRQL questionnaires before and after an intervention that impacted on HRQL. We used Pearson correlation coefficients and linear regression to assess the relationship between .
