Measurement properties of the Brazilian version of the Pediatric Quality of Life Inventory (PedsQL™) cancer module scale

BACKGROUND The use of health-related quality of life (HRQOL) measurements has been increased progressively in health surveys. These measurements document the functional and psychosocial outcomes of health conditions and complement clinical indicators to provide a comprehensive description of individuals and populations' health. The Pediatric Quality of Life Inventory (PedsQL) is a promising instrument with age-appropriate versions. The objective of the current paper was to evaluate the psychometric properties of the PedsQL 3.0 Cancer Module cross-culturally adapted for use in Brazil. METHODS A cross-sectional study was developed with 190 Brazilian families of individuals from 2 to 18 years of age, of both genders, with cancer in various phases of treatment or control. Subjects were recruited by means of convenience samples from the Pediatric Hematology/Oncology Centers at two public hospitals. 'In-treatment' status was defined as individuals who were receiving medical care to induce remission. 'Off-treatment' status was defined as individuals for whom all therapy was completed for a period of at least one month. Reliability was determined through test-retest reliability and internal consistency. The validity of the Cancer Module was determined through discriminant and convergent validity. Correlations between the scores obtained by the children/adolescents with cancer and their guardians were assessed. RESULTS Test-retest reliability demonstrated good correlation (0.69-0.90 for children/adolescents; 0.71-0.93 for guardians) and adequate agreement of the items (0.26-0.85 for children/adolescents; 0.25-0.87 for guardians). Internal consistency demonstrated adequate indices in comparisons between groups (alpha = 0.78-0.80 for children and adolescents; 0.68-0.88 for guardians). The 'pain and hurt', 'nausea', 'procedural anxiety' and 'treatment anxiety' subscales proved capable of distinguishing the groups of children in treatment and off treatment (p < 0.05). Positive significant correlations were observed between the scores of the PedsQL 3.0 Cancer Module and the PedsQL 4.0 Generic Core scales. Weak correlations were found between the reports of the children and those of the guardians. CONCLUSION The Brazilian version of the PedsQL 3.0 Cancer Module exhibited good measurement properties regarding reproducibility and construct validity.