Adaptation of the Mishel Uncertainty of Illness Scale (MUIS)for chronic patients in Italy

Rationale, aims and objectives Uncertainty is a component of the illness experience andis likely to increase the burden of managing chronic illness, as cardiac pathologies and renaldiseases. The impact of uncertainty should be taken into account and addressed withtargeted intervention programmes. The purpose of this study is to contribute to the diffusionof the assessment of uncertainty in illness by validating the Mishel uncertainty in illnessscale (MUIS) on chronic Italian patients.Method The MUIS questionnaire was administered to 200 patients suffering from cardiacdiseases and 50 patients with renal diseases.Aconfirmatory factor analysis was run for eachof the MUIS dimensions (ambiguity, inconsistency, complexity and unpredictability).Results After some item reduction, three of the four MUIS scales, namely, ambiguity,inconsistency and complexity, exhibited satisfactory reliability coefficients (withCronbach’s alphas of, respectively, 0.796, 0.778 and 0.705), highly significant standardizedregression weights and satisfactory/highly satisfactory fit indexes. Nevertheless, as thecorrelations among the scales mentioned earlier were high (all above 0.8) and statisticallysignificant, the three subsets of ambiguity, complexity and inconsistency items wereallowed to load onto a new single factor. A monodimensional uncertainty construct,grouping the majority of the items encompassed by these three MUIS scales, was successfullyvalidated.Conclusions This study provides researchers with an easy-to-administer instrument whichis useful to investigate a crucial aspect related with patients’ quality of life. Although aunique uncertainty construct is proposed, the in-depth analysis of the replies to each singleitem of the MUIS could help to monitor patients’ emotional responses to the diagnosis andto the course of this disease and it might be useful to define appropriate strategies of copingand to focus on patients’ quests for simplicity and clarity of treatment.