Development of the assessment of illness expectations in people with asthma

Abstract

Background: Every person who receives a diagnosis develops his/her expectations about the course of the disease. This is the main core of the concept of “Illness Expectation” (IE), a cognitive schema that defines the future-oriented beliefs about the illness and the symptoms of someone with a chronic disease.

Aims: The overall aim is the development of a reliable tool to assess illness expectations.

Method: We developed an “Illness Expectation Test”, which incorporates a self-reported questionnaire that included 24 multiple choice items and an IE-specific Implicit Association Test with stimuli related to illness improvement/worsening and self/others. The new instrument was validated for factorial structure and convergent validity.

Results: Based on 146 asthmatic responders, preliminary analyses suggest a 3-factorial structure, explaining about 70% of the variance. The three factors are labeled: absolute expectations (Cronbach’s alpha: .923), worsening (alpha: .963), and rigidity (alpha: .513). The first two factors are highly correlated (p<.001), while rigidity is only related to the absolute expectations scale (p<.05). The scores of the IE-IAT are negatively correlated with both the absolute expectations (p<.05) and worsening (p<.001), while no correlation was found with the rigidity scale. The scale seems to have good convergent validity, as the factors are highly correlated (p<.001 for the first two scales, p<.05 for rigidity) with the Brief Illness Perception Scale and the Illness Cognition Questionnaire. Interestingly, only the absolute expectation scale is associated (p<.001) with the Asthma Control Test.

Conclusions: Preliminary results suggest good implications for longitudinal studies.