Simple Logistic Models in the development of a quality of life questionnaire specific for patients with Chronic Obstructive Pulmonary Disease

Simple Logistic Models add criteria to choice the optimal number of items designed for Italian patients affected by Chronic Obstructive Pulmonary Disease

A new questionnaire specifically designed for patients affected by chronic obstructive pulmonary disease. The Italian Health Status Questionnaire

SummaryThe aim of this study was to develop a specific and valid questionnaire for Italian COPD patients, living on the north or the south of Italy—which are two culturally distinct areas.The project consisted in three steps: (1) initial item set generation to identify items relevant to both genders, all ages and both regions; (2) item reduction including tests of regional specificity; (3) tests of internal validity using item-response theory using Rasch one-parameter modelling.Ninty-six COPD patients (mean aged 69yr; 78 Male) completed the original set of 124 items of the Italian Health Status Questionnaire (IHSQ). Item reduction was carried out using an established standardised approach e…