Evaluation of a revised instrument to assess the needs of men diagnosed with prostate cancer

Background: This study was conducted to assess the face, content and construct validity and the internal validity of the revised version of an instrument to measure the perceived needs of men diagnosed with prostate cancer [Prostate Cancer Needs Questionnaire version 2 (PCNQv2)]. The PCNQ was constructed in two parts with Part 1 measuring needs at diagnosis and initial treatment and Part 2 measuring current needs. Methods: A random sample of 650 men diagnosed with prostate cancer attending a Urologist of the Hunter Urology Group in Newcastle, New South Wales, Australia, were invited to participate in the study and sent by post the self-administered PCNQ. Information was provided on 145 men who were considered ineligible to participate. Completed questionnaires were received from 300 men. Results: The principal components method of factor analysis with varimax orthogonal rotation identified eight factors with eigenvalues greater than 1, which together accounted for 68% of the variance in Part 1 of the PCNQ. Likewise, six factors were identified in Part 2 which accounted for 68% of the variance. Internal reliability coefficients (Cronbach's alpha) were adequate for identified factors with values ranging from 0.71 to 0.90 for Part 1, and from 0.80 to 0.92 for Part 2. Conclusions: These results support the validity and reliability of the PCNQv2 to assess the perceived needs experienced by men diagnosed with prostate cancer.