Differences in the process of development and the content of four health-related quality of life (HRQL) questionnaires for children and adolescents.

RAJMIL L; ALONSO J; ELORZA JM; BERRA S; AYMERICH M; RAVENS-SIEBERER U; KOCH R; SIMEONI MC; PATRICK D

Praga (República Checa)

Congreso; ISOQOL meeting; 2003

International Society of Quality of Life

Although there is agreement on the multi-dimensional nature of HRQL, the content of measuring instruments has been insufficiently reviewed, especially for the younger ages. The objective of this study was to analyse and compare the content of four instruments included in the pilot test of the Kidscreen project, a new HRQL instrument developed in Europe. Instruments included were: the VSP-A (France); the Kindl (Germany); the Youth QoL (the US); and the Kidscreen (seven European countries). Information reviewed included: initial item pool generation, item reduction methods, the final items and dimensions, and the scoring methods as well as the populations on which they were carried out. A modified MOT Scientific Committee Criteria to evaluate HRQL instruments was used for assessing their relative quality. Items had been generated through focus group with adolescents in three cases, and lay and professionals for the remaining (Kindl). Item reduction was based on Classical Testing in all cases, but for the Kidscreen Item Response Theory was also used. The number of dimensions ranged from four dimensions (Kindl and YQOL), to 10 (Kidscreen). The total number of items ranged from 24 (Kindl) to 53 (Kidscreen), with more items addressing social than physical functioning. All questionnaires allow to built a single index. The Kidscreen and VSP-A included only healthy adolescents in its development, while Kindl and YQOL included both healthy and disabled children or with chronic conditions. MOT scale scores of the four instruments were similar. HRQL instruments for adolescents and children evaluated are multidimensional and have followed a satisfactory development.