Table 2.
Objective knowledge of cancer genetics.
| Total Sample n = 1933 |
Study 1 (2007) n = 370 |
Study 2 (2013) n = 1290 |
Study 3 (2019) n = 273 |
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|---|---|---|---|---|---|---|---|---|---|---|---|---|
| GC (+) * n = 745 |
GC (−) ^ n = 1188 |
GC (+) n = 200 |
GC (−) n = 170 |
GC (+) n = 313 |
GC (−) n = 977 |
GC (+) n = 232 |
GC (−) n = 41 |
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| Correct (%) | p | Correct (%) | p | Correct (%) | p | Correct (%) | p | |||||
| Cancer can be caused by a pathogenic variant passed on from one generation to the next | 91.4 | 76.0 | <0.0001 | 96.5 | 91.2 | 0.05 | 86.3 | 72.7 | <0.0001 | 94.0 | 92.7 | 0.72 |
| Families with a pathogenic variant in the BRCA1 or BRCA2 genes are likely to have cases of breast cancer in more than one generation | 84.6 | 53.5 | <0.0001 | 87.5 | 57.6 | <0.001 | 77.6 | 51.4 | <0.0001 | 91.4 | 87.8 | 0.55 |
| A woman’s risk for getting breast cancer is higher when she… | ||||||||||||
| …has a family history of ovarian cancer | 74.6 | 51.1 | <0.0001 | 80.5 | 69.4 | 0.01 | 65.5 | 47.5 | <0.0001 | 81.9 | 61.0 | 0.004 |
| …has a relative diagnosed with breast cancer younger than 50 years old | 57.9 | 63.6 | 0.01 | 72.0 | 61.8 | 0.04 | 76.7 | 66.1 | <0.001 | 20.3 | 12.2 | 0.31 |
| …has a family history of breast cancer from the dad’s side of the family | 74.6 | 56.7 | <0.0001 | 88.5 | 87.1 | 0.79 | 62.3 | 51.4 | <0.001 | 79.3 | 58.5 | <0.01 |
| …has a family history of breast cancer from the mom’s side of the family | 87.8 | 77.3 | <0.001 | 93.5 | 92.9 | 0.99 | 82.7 | 75.1 | <0.01 | 89.7 | 63.4 | <0.001 |
| …has breast and ovarian cancer in the same side of the family | 82.0 | 68.7 | <0.0001 | 88.0 | 85.3 | 0.54 | 78.9 | 66.6 | <0.0001 | 81.0 | 48.8 | <0.001 |
| …has a pathogenic variant in the BRCA1 or BRCA2 genes | 88.1 | 53.7 | <0.0001 | 89.0 | 76.5 | <0.01 | 82.1 | 49.0 | <0.0001 | 95.3 | 61.0 | <0.0001 |
| …is from Ashkenazi Jewish descent | 38.3 | 13.5 | <0.0001 | 62.5 | 33.5 | <0.001 | 32.2 | 10.3 | <0.0001 | 25.4 | 4.9 | <0.01 |
| …has a male relative who had breast cancer | 65.1 | 47.8 | <0.0001 | 73.0 | 65.9 | 0.17 | 60.1 | 44.7 | <0.0001 | 65.1 | 46.3 | 0.03 |
| …has a relative with breast cancer in both breasts | 78.9 | 68.3 | <0.001 | 86.0 | 85.3 | 0.96 | 75.1 | 65.9 | <0.01 | 78.0 | 53.7 | 0.001 |
| …has a relative who had both breast and ovarian cancer | 82.6 | 71.5 | <0.001 | 85.0 | 84.1 | 0.92 | 81.5 | 69.8 | <0.0001 | 81.9 | 61.0 | <0.01 |
| …has multiple relatives with breast cancer | 81.7 | 80.6 | 0.58 | 91.5 | 94.1 | 0.44 | 84.7 | 79.7 | 0.06 | 69.4 | 46.3 | <0.01 |
| Total correct answers (0–13)—mean (SD) |
9.9 (3.2) | 7.8 (3.8) | <0.0001 | 10.9 (2.9) | 9.8 (2.9) | <0.001 | 9.5 (3.6) | 7.5 (3.8) | <0.0001 | 9.5 (2.8) | 7.0 (3.9) | 0.0002 |
* GC (+) Counselled; ^ GC (−) Not counselled. Bold: p-value still significant after Bonferroni correction.