Janine M Duke1, Carla J Treloar, Julie E Byles. 1. Centre for Clinical Epidemiology and Biostatistics, The University of Newcastle, Royal Newcastle Hospital, Newcastle, NSW, Australia. jduke@cceb.newcastle.edu.au
Abstract
BACKGROUND: This study was conducted to evaluate a self-administered questionnaire developed to measure the needs experienced by men diagnosed with prostate carcinoma (the Prostate Cancer Needs Questionnaire [PCNQv1.1]). The PCNQv1.1 was constructed in two parts. Part 1 measures the needs at diagnosis and initial treatment and Part 2 measures current needs. METHODS: A random sample of 650 men diagnosed with prostate carcinoma who were being treated by a urologist of the Hunter Urology Group in Newcastle, New South Wales, Australia, were invited to participate in the study. They were sent by post the self-administered PCNQv1.1. Completed questionnaires were received from 385 men. Information provided on 100 additional men was considered ineligible. RESULTS: The principal components method of factor analysis with varimax orthogonal rotation identified eight factors with eigenvalues greater than 1, which accounted for 61.7% of the variance in Part 1 of the PCNQv1.1. Likewise, six factors were identified in Part 2, which accounted for 63.5% of the variance. Internal reliability coefficients (Cronbach alpha) were adequate for identified factors with values ranging from 0.70 to 0.88 for Part 1 and from 0.71 to 0.87 for Part 2. Test-retest reliability was acceptable with intraclass correlation coefficients ranging from 0.61 to 0.78 for Part 1 and from 0.60 to 0.82 for Part 2. CONCLUSIONS: These results suggest that the PCNQv1.1 is a valid and reliable instrument to assess the needs experienced by men diagnosed with prostate carcinoma. Copyright 2003 American Cancer Society
BACKGROUND: This study was conducted to evaluate a self-administered questionnaire developed to measure the needs experienced by men diagnosed with prostate carcinoma (the Prostate Cancer Needs Questionnaire [PCNQv1.1]). The PCNQv1.1 was constructed in two parts. Part 1 measures the needs at diagnosis and initial treatment and Part 2 measures current needs. METHODS: A random sample of 650 men diagnosed with prostate carcinoma who were being treated by a urologist of the Hunter Urology Group in Newcastle, New South Wales, Australia, were invited to participate in the study. They were sent by post the self-administered PCNQv1.1. Completed questionnaires were received from 385 men. Information provided on 100 additional men was considered ineligible. RESULTS: The principal components method of factor analysis with varimax orthogonal rotation identified eight factors with eigenvalues greater than 1, which accounted for 61.7% of the variance in Part 1 of the PCNQv1.1. Likewise, six factors were identified in Part 2, which accounted for 63.5% of the variance. Internal reliability coefficients (Cronbach alpha) were adequate for identified factors with values ranging from 0.70 to 0.88 for Part 1 and from 0.71 to 0.87 for Part 2. Test-retest reliability was acceptable with intraclass correlation coefficients ranging from 0.61 to 0.78 for Part 1 and from 0.60 to 0.82 for Part 2. CONCLUSIONS: These results suggest that the PCNQv1.1 is a valid and reliable instrument to assess the needs experienced by men diagnosed with prostate carcinoma. Copyright 2003 American Cancer Society