Interpreting the meaningfulness of changes in health-related quality of life scores: lessons from studies in adults.

The measurement of health-related quality of life (HRQL) in adults with cancer has proceeded more quickly than has similar measurement in children, so there may be value in applying some methods used in adults to studies in children. An example is a health-transition state instrument called the Subjective Significance Questionnaire (SSQ). The SSQ asks patients to give their own estimates of the degree to which their HRQL has changed with time and, thus, provides a method for interpreting the meaningfulness of changes in scores as derived from a general questionnaire, the EORTC QLQ-C30. The development of similar health-transition instruments for children poses special challenges and requires the development of appropriate methodology. It is suggested that, with the use of cartoons and the answers of proxies, it should be feasible to assess the meaningfulness of changes in HRQL over time in young children as well as in adolescents. Int. J. Cancer Suppl. 12:132-137, 1999. Copyright 1999 Wiley-Liss, Inc.