Providing objective performance indicators can improve agreement between observed function and self-reported ability, perhaps by counteracting a response shift.
The stable levels of impact on HRQL of partners may be explained by the existence of a response shift, 28 where partners who have stayed in the relationship with PwMS revise their prior values and the relative impact of MS. However, the impact on partner's HRQL did not decrease over time, which implies the need for continuous MS care efforts including focus on partners.
However, if a respondent shows a response shift by changing the manner in which he or she completes the measure, this may confound interpretation of the treatment effect.
Further, patients might be reassured by a performance test that counteracts a response shift whereby they overestimate their disability, thereby possibly reducing health care expenditures by anxious patients seeking reassurance.
Investigation of the impact of cancer treatment on fatigue is compromised by a potential "response shift" in fatigue ratings, involving a recalibration of a respondent's internal standard used to judge their current fatigue experience.
These findings, could however, be biased by a phenomenon called response shift, which could have resulted in an underreporting of functional disabilities in the group with the longest duration of complaints [ 40].
HRQoL even improved slightly over time, which may be partially explained by a so-called response shift; i.e., although patients experience a change in health over time, they become more readily to accept their situation.
This difference in perspective might lead to unequal results for utility measurements which can be explained by a phenomenon called response shift.
Additionally, the relationship between ratings of HRQoL dimensions at two different time points, e.g., from baseline to 6-month later could theoretically explain by a model called "response shift" [ 58].
The change in internal standards or values proposed by the response shift theory was therefore only partially supported by our data.
