Change of perspective: a measurable and desired outcome of chronic disease self-management intervention programs that violates the premise of preintervention/postintervention assessment
posted on 2006-06-01, 00:00authored byRichard Osborne, Melanie Hawkins, M Sprangers
Objective: To determine if participants in chronic disease self-management courses have a change of perspective of their health status (a response shift), and if this is measurable with a paper-based questionnaire. Methods: Nine items were developed to measure potential benefits of self-management courses. These were based on the constructs of a previous questionnaire, the Health Education Impact Questionnaire (HEI-Q). Cognitive interviews elicited spontaneous statements about the reasons for paper-based answers. Sensitivity, specificity, and overall accuracy of items were calculated using the interview as a relative gold standard. Response shift can be negative (i.e., after the course, participants realize that, before the course, they were worse than they thought they were), positive (i.e., participants now realize they were better than they thought they were), or absent (no change).
Results: Interviews (n = 39) reflected that true response shift occurred in approximately half the replies to questionnaire items. Of these, 31% were negative response shift, 20% were positive response shift. Response shift was absent in 32% of replies. Presence or absence of response shift could not be determined in 17% of replies across items. Significant concordance between questionnaires and cognitive interviews (average overall accuracy 0.79) indicated that the HEI-Q Perspective questionnaire detects response shift in participants of self-management courses. The questionnaire revealed that 87% of participants had response shift in at least 1 item.
Conclusion: This study suggests that preintervention/postintervention assessments of interventions such as self-management courses are confounded by a change in perspective of a large proportion of respondents. It also indicates response shift is a valuable outcome of self-management courses that can be measured with a paper-based questionnaire.