[Construct validity of the Information and Decisions in Asthma questionnaire]

To establish the construct validity of a new scale based on the Information and Decisions in Asthma (IDEA) questionnaire, which was designed to detect an asthmatic's desire to receive information, active seeking out of information and ability to make decisions about his or her disease.

The IDEA questionnaire containing 31 items in three subscales: desire for information (DI), seeking out information (SI) and decision making (DM) was answered by 120 asthmatic adults (54 men and 66 women; 86 intrinsic and 44 extrinsic) in stable condition and with varying levels of severity of disease. After interviews to take down medical histories (age of onset, years of evolution, visits to the emergency room within the past year), educational level and economic status, all patients completed a battery of tests assessing the following: quality of life (QL), alexithymia (TAS-20), health opinions (HOS), state-trait anxiety (STAI-E/R), asthma symptoms control (ASC), health locus control (HLC), somatosensory amplification (SAS) and personality (NEO-PI).

Although most patients expressed interest in obtaining information, their level of active seeking and decision making were much lower. DI and SI were associated with higher educational levels and economic status, whereas DM correlated with the presence of atopy, age (young patients), sex (women) and few visits to the emergency room. Multiple regression analysis of psychological variables showed that DI and SI were accounted for mainly by the absence of alexithymia, whereas DM depended on an individual's behavioral involvement with his or her disease.

The global analysis of these results indicate that the IDEA questionnaire has satisfactory construct validity, given that its dimensions are associated with sociodemographic and psychological characteristics that can be expected given its conceptual content.