Psychometric evaluation of a questionnaire to document side-effects of chemotherapy.
This paper reports the psychometric testing of the Worthing Chemotherapy Questionnaire (WCQ). The WCQ is a patient self-report instrument to document side-effects of chemotherapy. Literature review of relevant studies shows that psychometric testing of similar instruments is rarely rigorous. Content validity for the WCQ was established in five ways: literature review, Delphi review among oncology staff, pre-pilot unstructured interviews, pilot study and amendment of the instrument and items for spontaneous reporting of problems on the questionnaire. A three-stage approach to construct validity was used. The hypothesis adopted was that as certain cytotoxic agents cause stomatitis, incidence and severity of stomatitis will decrease following cessation of treatment. Stage 1: factor analysis confirmed the presence of a sole factor, with an eigenvalue of 5.3, for mouth problems which explained 65.5% of the variance. Stage 2: the hypothesis was confirmed using research findings. Stage 3: the Wilcoxon test showed highly significant results for during and post chemotherapy stomatitis scores. Reliability of the questionnaire was assessed using the test-retest method. Weighted kappa was chosen as the test statistic. A median value of wk = 0.87 was obtained. The results indicate that the WCQ is a reliable and valid instrument.
Sitzia
J
J
Day Ward Nursing Development Unit, Worthing Hospital, Worthing, England.
Dikken
C
C
Hughes
J
J
D000970:Antineoplastic Agents / Q000009:adverse effects*; D005163:Factor Analysis, Statistical; D006801:Humans; D016555:Matched-Pair Analysis; D009369:Neoplasms / Q000188:drug therapy*; D010865:Pilot Projects; D011594:Psychometrics; D015203:Reproducibility of Results; D018709:Statistics, Nonparametric; D013280:Stomatitis / Q000139:chemically induced; D011795:Surveys and Questionnaires
D000970:Antineoplastic Agents