Response shift in quality of life assessment in patients with chronic back pain and chronic ischaemic heart disease.
OBJECTIVE
To examine the extent and type of influence of response shift (RS) (reconceptualization, reprioritization, recalibration) on the assessment of changes in health-related quality of life (HRQoL) after the inpatient rehabilitation of patients with chronic back pain and chronic ischaemic heart disease.


METHODS
RS was assessed using the then-test and structural equation modelling (SEM) approaches. HRQoL was recorded in a questionnaire study at the start and end of rehabilitation using disease-specific instruments. Global items were also developed to collect data on HRQoL at the start and end of rehabilitation, as well as for the retrospective evaluation of HRQoL at the beginning of rehabilitation via the then-test.


RESULTS
There are small recalibration effects in the then-test in both diseases in nearly every item which may underestimate the actual effects of change. Using the SEM approach, uniform and non-uniform recalibration effects appear in a few of the scales that cause true change scores to be under- and over-estimated.


CONCLUSIONS
RS reflects a phenomenon that should be included when assessing HRQoL to allow a more valid interpretation of treatment effects. The results of SEM approach, however, suggest that RS does not lead to fundamentally different results in rehabilitation effects.
Department of Quality Management and Social Medicine, University Freiburg-Medical Center, Freiburg, Germany. michaela.nagl@uniklinik-freiburg.de
Michaela
M
Nagl
Erik
E
Farin
D000328:Adult; D000368:Aged; D002908:Chronic Disease; D059350:Chronic Pain / Q000503:physiopathology / Q000523:psychology; D005260:Female; D005500:Follow-Up Studies; D006304:Health Status; D006801:Humans; D017116:Low Back Pain / Q000523:psychology* / Q000534:rehabilitation; D008297:Male; D008875:Middle Aged; D008962:Models, Theoretical; D017202:Myocardial Ischemia / Q000523:psychology* / Q000534:rehabilitation; D010147:Pain Measurement; D011788:Quality of Life / Q000523:psychology*; D020127:Recovery of Function; D012189:Retrospective Studies; D018434:Sickness Impact Profile; D012959:Socioeconomic Factors; D011795:Surveys and Questionnaires; D016896:Treatment Outcome