Development of a scale to assess patient misperceptions about treatment choices for localized prostate cancer.

Objectives: To develop a questionnaire to assess a patient's knowledge of his cancer, understanding of treatment choices, and judgement of his survival (KUJ) with and without treatment, as treatment for localized prostate cancer (LPC) can lead to urinary, sexual and bowel side-effects and might not improve survival in 75% of patients.

Patients And Methods: Although >90% of patients in the USA are diagnosed with LPC, approximately 94% of them choose treatment, such that newly diagnosed patients need individualized counselling to address misperceptions about the management of LPC. The internal consistency of an 18-item KUJ scale was evaluated among 184 patients recently diagnosed with LPC at a major urology practice. Principal-component analyses were applied for computing a KUJ index. Logistic regression modelling was used to identify predictors of the KUJ index.

Results: Cronbach's alpha for the KUJ scale was 0.76. Nearly half of the patients provided incorrect answers to most KUJ items. Of the patients, 68% had an income of >US$50,000 and 90% had at least high (or secondary) school literacy level. Quality-of-life measures suggested that most patients were physically, mentally and socially healthy. Higher education, income and functional capacity were associated with worse KUJ.

Conclusion: The KUJ scale is internally consistent and clinicians can use it to identify the educational needs of patients with LPC before treatment selection. Overall, patients who were socioeconomically disadvantaged and those with physical ailments were better informed about the diagnosis, treatment options and prognosis of prostate cancer.