Brief report: psychometric evaluation of the severity of illness scale in a pediatric oncology sample.

OBJECTIVE

To examine the psychometric properties of the Severity of Illness Scale (SOIS), a measure that focuses on the medical severity of illness of children with cancer, from the point of view of medical personnel.

METHODS

Following pretesting, the SOIS was administered to nurses and physicians of 55 pediatric cancer patients at three time periods: entry into study, 2-week follow-up, and 3-month follow-up. Validity determination included analyses of relapse status and bone marrow transplant. Test utility was determined via a respondent questionnaire.

RESULTS

Test-retest reliability coefficients were .96 and .92 for 2-week and 3-month time periods. Interrater reliability, assessed by comparing physician ratings to nurse ratings, was .89. Evidence for criterion-related validity revealed that the SOIS discriminates both bone marrow transplant and relapse status. Physicians and nurses rated the SOIS positively for brevity, ease of completion, and usefulness in depicting medical severity of disease.

CONCLUSIONS

There is preliminary evidence for the psychometric utility of the Severity of Illness Scale for a pediatric cancer population. The inclusion of illness parameters in current models of risk and resiliency dictate the need for such a measure.