The perceived severity of a disease and the impact of the vocabulary used to convey information: using Rasch scaling in a simulated oncological scenario

Roberto Burro,1 Ugo Savardi,1 Maria Antonietta Annunziata,2 Paolo De Paoli,2 Ivana Bianchi3 1Department of Human Sciences, University of Verona, 37129 Verona, Italy; 2National Cancer Institute IRCCS “Centro di Riferimento Oncologico” (CRO), 33080 Aviano (PN), Italy; 3Department of Humanities (section Philosophy and Human Sciences), University of Macerata, 62100 Macerata, Italy Background: Healthcare staff should be aware of the importance that patients may attach to the words that are used to convey information. This is relevant in terms of the patients’ understanding. Modeling how people understand the information conveyed in a medical context may help health practitioners to better appreciate the patients’ approach. Purpose: 1) Analyze the participants’ self-reported perception of the type of information provided in an oncological scenario in terms of three dimensions: impairment to their health, risks associated with the disease itself and commitment required to undergo the treatment; and 2) show the benefits of using Rasch scaling for the analysis of the data. Starting from a survey, Rasch scaling produces a unidimensional logit-interval scale relating to the extent to which each item conveys a latent dimension. These were related to structure, in particular concerning communication by means of opposite vs. unipolar language. Subjects and methods: The participants rated 82 items of information in a questionnaire regarding their perception of impairment to their health (H) and the risks (R) and commitment relating to the treatment prescribed (T). Results: The scaling produced an item bank for healthcare staff to consult in order to estimate the importance the recipient would be likely to attach to the vocabulary used and the likely impact of the information in terms of the patient’s condition. Furthermore, the use of opposites was generally associated with a clearer impression of whether the information given was generally only very negative or slightly negative, whereas ‘neutral’ information was often perceived as being very negative. Actual findings: Is possible to estimate people’s understanding more precisely (in terms of H, R and T) which can help healthcare practitioners to modulate the way they convey information. Limitations: The participants in the study were healthy volunteers and the context was simulated. Keywords: Rasch model, simulated oncological scenario, perceived severity of impairment to health, perception of risk, perceived commitment to the treatment, opposites