Facilitating Participation in a Prostate Cancer Risk Assessment Program

Primary outcomes

1. Pca Risk-related Knowledge

   Time frame: three weeks

   Knowledge about Pca risk was measured using an eight item scale prepared for this study. It consisted of true/false items [e.g., "An abnormal digital rectal examination (DRE) and/or prostate-specific antigen (PSA) could be the result of conditions other than prostate cancer"]. Correct responses received a value of one, whereas false responses received a zero. Values ranged between zero and eight. Higher score means better knowledge of risk and issues.

2. Pca Perceived Risk

   Time frame: three weeks

   Perceived risk of Pca was assessed using four items where participants were asked to estimate their prostate cancer risk in general (e.g., "Do you feel as though you are the kind of person who is likely to develop prostate cancer?") or comparing themselves to other men at risk for Pca (e.g., "Given your ethnicity, what are your chance of getting prostate cancer?") on a five-point scale (Lerman et al., 1996). Reported means are based on a scale from one to five (based on the average of the four items). Cronbach's alpha for the scale was 0.83. A higher score indicates higher Pca perceived risk.

3. Pca-related Positive Expectations

   Time frame: three weeks

   Positive expectations regarding the effects of screening were assessed using two items on a five-point scale ("Regular screening will ensure that I stay healthy" and "Regular screening will prolong my life"). Questionnaire items were author-constructed, based on our prior work and cognitive-affective theory (Miller et al., 1996). Reported means are based on a scale from one to five (average of the two items). Cronbach's alpha for the scale was 0.76. Higher score indicates more positive expectations.

4. Negative Expectations Regarding Pca Risk

   Time frame: three weeks

   Negative expectations related to Pca screening comprised five items and assessed the costs and risks of screening, in terms of time and effort, fears of discrimination, insurance and employment, and financial concerns on a five-point scale (e.g., "Screening may have a negative impact on my health insurance"). Questionnaire items were author-constructed, based on our prior work and cognitive-affective theory (Miller et al., 1996). Reported means are based on a scale from one to five (average of five items). Cronbach's alpha for the scale was 0.80. A higher score indicates more negative expectations.

5. Pca Related Intrusive Ideation

   Time frame: three weeks

   Intrusive ideation related to prostate cancer risk was assessed using the Impact of Events Scale (IES) (Horowitz et al., 1979). The full scale consists of two subscales, intrusive ideation and avoidant ideation. In this study only the intrusive ideation subscale was used. The instrument has been used extensively in the cancer literature (Schwartz et al., 2002). Values range from 0 to 35, with higher values indicating a higher level of intrusive ideation. Cronbach's alpha for the intrusion subscale in the present study was 0.82. Because of high skewness, a median split was used to create a high intrusive ideation group and a low intrusive ideation group.

6. Pca Risk-related Knowledge

   Time frame: six months

   Knowledge about Pca risk was measured using an eight item scale prepared for this study. It consisted of true/false items [e.g., "An abnormal digital rectal examination (DRE) and/or prostate-specific antigen (PSA) could be the result of conditions other than prostate cancer"]. Correct responses received a value of one, whereas false responses received a zero. Values ranged between zero and eight. Higher score means better knowledge of risk and issues.

7. Pca Perceived Risk

   Time frame: six months

   Perceived risk of Pca was assessed using four items where participants were asked to estimate their prostate cancer risk in general (e.g., "Do you feel as though you are the kind of person who is likely to develop prostate cancer?") or comparing themselves to other men at risk for Pca (e.g., "Given your ethnicity, what are your chance of getting prostate cancer?") on a five-point scale (Lerman et al., 1996). Reported means are based on a scale from one to five (based on the average of the four items). Cronbach's alpha for the scale was 0.83. A higher score indicates higher Pca perceived risk.

8. Pca-related Positive Expectations

   Time frame: six months

   Positive expectations regarding the effects of screening were assessed using two items on a five-point scale ("Regular screening will ensure that I stay healthy" and "Regular screening will prolong my life"). Questionnaire items were author-constructed, based on our prior work and cognitive-affective theory (Miller et al., 1996). Reported means are based on a scale from one to five (average of the two items). Cronbach's alpha for the scale was 0.76. Higher score indicates more positive expectations.

9. Negative Expectations Regarding Pca Risk

   Time frame: Six months

   Negative expectations related to Pca risk screening comprised five items and assessed the costs and risks of screening, in terms of time and effort, fears of discrimination, insurance and employment, and financial concerns on a five-point scale (e.g., "Screening may have a negative impact on my health insurance"). Questionnaire items were author-constructed, based on our prior work and cognitive-affective theory (Miller et al., 1996). Reported means are based on a scale from one to five (average of five items). Cronbach's alpha for the scale was 0.80. A higher score indicates more negative expectations.

10. Pca Related Intrusive Ideation

    Time frame: Six months

    Intrusive ideation related to prostate cancer risk was assessed using the Impact of Events Scale (IES) (Horowitz et al., 1979). The full scale consists of two subscales, intrusive ideation and avoidant ideation but only the intrusive ideation subscale was used in the present study. The instrument has been used extensively in the cancer literature (Schwartz et al., 2002). Cronbach's alpha for the intrusion subscale in the present study was 0.82. Values range from zero to 35, with higher values indicating higher level of intrusive ideation. Because of high skewness, a median split was used to create a high intrusive ideation group and a low intrusive ideation group.