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

Abstract

Uncertainty is a component of the illness experience and is likely to increase the burden of managing chronic illness, as cardiac pathologies and renal diseases. The impact of uncertainty should be taken into account and addressed with targeted intervention programmes. The purpose of this study is to contribute to the diffusion of the assessment of uncertainty in illness by validating the Mishel uncertainty in illness scale (MUIS) on chronic Italian patients. The MUIS questionnaire was administered to 200 patients suffering from cardiac diseases and 50 patients with renal diseases. A confirmatory factor analysis was run for each of the MUIS dimensions (ambiguity, inconsistency, complexity and unpredictability). After some item reduction, three of the four MUIS scales, namely, ambiguity, inconsistency and complexity, exhibited satisfactory reliability coefficients (with Cronbach's alphas of, respectively, 0.796, 0.778 and 0.705), highly significant standardized regression weights and satisfactory/highly satisfactory fit indexes. Nevertheless, as the correlations among the scales mentioned earlier were high (all above 0.8) and statistically significant, the three subsets of ambiguity, complexity and inconsistency items were allowed to load onto a new single factor. A monodimensional uncertainty construct, grouping the majority of the items encompassed by these three MUIS scales, was successfully validated. This study provides researchers with an easy-to-administer instrument which is useful to investigate a crucial aspect related with patients' quality of life. Although a unique uncertainty construct is proposed, the in-depth analysis of the replies to each single item of the MUIS could help to monitor patients' emotional responses to the diagnosis and to the course of this disease and it might be useful to define appropriate strategies of coping and to focus on patients' quests for simplicity and clarity of treatment.