Development and preliminary evaluation of the validity and reliability of a revised illness perception questionnaire for healthcare professionals

Seher Arat, Anke Van den Zegel, Maity Van Rillaer, Philip Moons, Joris Vandenberghe, Ellen De Langhe, René Westhovens

Diverging perceptions between individual patients with somatic diseases and their healthcare professionals might cause problems in communication and decision-making. To date, no measurement tool is available to compare the illness perceptions between these two groups. The Revised Illness Perception Questionnaire (IPQ-R) is a validated, widely used instrument in many patient populations with somatic conditions. The aim of this study was to adapt the IPQ-R to a healthcare professional's version (IPQ-R HP) and to perform a preliminary evaluation of its validity and reliability. After adaptation of the IPQ-R HP, 17 doctors from 3 general hospitals and 9 head nurses from a university hospital evaluated the face and content validity of the IPQ-R HP. The results were quantified using the content validity index (CVI) and a modified kappa index (k*). For the reliability measurements a group of nurses from 4 nursing wards participated at 2 time points with an interval of 4 weeks. Internal consistency and test-retest reliability were calculated. Twenty-eight of the 38 items demonstrated excellent content validity and four items showed good content validity. Four items had a sufficient k* and two items had a low CVI. The average CVI of the 7 dimensions ranged from 0.66 to 0.89. The Cronbach's alpha scores for the seven dimensions, intraclass coefficients and effect size estimates were acceptable. This preliminary evaluation of the IPQ-R HP shows an acceptable to good validity and reliability. Further exploration of the psychometric properties of this questionnaire in a large cohort of healthcare professionals is warranted.