Provided in , are the characteristics of the sibling and BRFSS samples. The mean age at the time of questionnaire completion for the sibling population was 33.5 years (range 18.0 - 58.0 years). The mean age of the sibling at the time of cancer diagnosis was 9.0 years (range -10.1 - 36.3 years). Fifty-four percent of the siblings (n=1392) were born before their survivor and 46% of the siblings (n=1196) were born after their survivor. There was a mean interval of 25.1 years (range 17.1-35.0 years) between the time of cancer diagnosis and sibling completion of the questionnaire.
Characteristics of the CCSS sibling populations and the age, gender, and race-matched random samples of participants from the BRFSS
Sibling and Survivor Concordance of Cancer Prevention and Screening Behaviors
The practice of sunscreen use was shared by both siblings and survivors 23.1% of the time. For protective clothing use, this practice was shared by 3.2% of the siblings and survivors. For hat use, siblings and survivors reported a similar commitment to this skin cancer prevention behavior 13.5% of the time. Shade use was reported by both siblings and survivors 11.7% of the time. In contrast, concordance between the practice of breast and cervical cancer screening practices of female siblings and survivors was higher. With respect to Pap testing, 82.2% of siblings and survivors report this behavior. Of those female siblings and survivors ≥40 years of age, concordance for the practice of mammography was 77.2%.
Adjusted Analysis of Cancer Prevention and Screening Behaviors
reports the frequencies of the cancer prevention and screening behaviors for the sibling and the BRFSS populations adjusted for age, sex, race/ethnicity, education, income, and region. The siblings were more likely to report skin cancer prevention behaviors including protective clothing use (OR 2.85, 95% CI: 2.39-3.39), shade use (OR 2.11, 95% CI: 1.88-2.36), sunscreen use (OR 1.27, 95% CI: 1.14-1.40), and hat use (OR 1.77, 95% CI: 1.58-1.98) compared to the BRFSS individuals after controlling for age, gender, race/ethnicity, education, income, and region (p<0.001, all outcomes). No differences were noted with respect to cervical or breast cancer screening practices such as Pap testing (p=0.55) or mammography (p=0.12) after adjusting for age, race/ethnicity, education, and income.
Percentages of CCSS siblings and the age, gender, and race-matched sample from BRFSS reporting cancer prevention and screening behaviors as well as adjusted odds ratios for each category
Multivariable Analysis for Sibling Cancer Prevention and Screening Behaviors
reports the multivariable analyses of factors impacting sibling skin cancer prevention behaviors. Being of male sex was consistently associated with skin cancer prevention behaviors as demonstrated by increased use of clothing (OR 1.69, 95% CI: 1.29-2.21) and increased use of hats (OR 4.44, 95% CI: 3.55-5.59), but less use of sunscreen (OR 0.59, 95% CI: 0.49-0.70) and shade (OR 0.72, 95% CI: 0.59-0.87). Sibling age was also associated diminished practice of a subset of skin cancer prevention behaviors. Younger sibling age (i.e., 18-29 years) was associated with decreased protective clothing use (OR 0.39, 95% CI: 0.19-0.82) and shade use (OR 0.46, 95% CI: 0.27-0.79) when compared to siblings ≥50 years of age. Other sibling demographic factors predicting a subset of the skin cancer protective behaviors including being of White non-Hispanic race/ethnicity which was associated with an increase in sunscreen use (OR 2.00, 95% CI: 1.40-2.90), but less use of shade (OR 0.60, 95% CI: 0.43-0.84).
Multivariable Models For Sibling Skin Cancer Prevention Behaviors†
reports the adjusted analyses of factors impacting sibling breast and cervical cancer screening behaviors. Sibling health insurance was the only sibling factor associated with the practice of both breast and cervical cancer screening. The presence of health insurance was associated with greater use of Pap testing (OR2.11, 95% CI: 1.13-3.80) and greater use of mammography (OR 6.36, 95% CI 1.40-28.6). Being a sibling of White non-Hispanic race/ethnicity was associated with greater Pap testing.
Multivariable Models For Sibling Cervical and Breast Cancer Prevention and Screening Behaviors†
With few exceptions, there were no significant associations between the survivor's diagnosis, the intensity of the survivor's treatment, the presence or absence of a chronic health condition in the survivor, psychological distress in the survivor, second cancers, across skin cancer prevention behaviors as well as breast and cervical cancer screening practices. A survivor diagnosis of a sarcoma or a bone tumor was associated with greater use of protective clothing and hat use among siblings when compared to a survivor diagnosis of leukemia. Fair/poor survivor health status was associated with greater use of protective clothing and Pap testing among siblings. The presence of a non-melanoma skin cancer in the survivor was not associated with skin cancer prevention behaviors in the siblings.