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["Additional data file 2: Characteristics of the sample from the MRC National Survey of Health and Development study (NSHD)."]
[]
["FACTORS",null,"Breast Cancer developed",null,"P value"]
[null,null,"Yes","No"]
["HRT ever used by 2003","Yes",12,78,0.81]
[null,"No",7,55]
["Miscarriage/Stillbirth by 43 years","Yes",4,22,0.75]
[null,"No",15,106]
["Number of live births","Yes",18,116,0.47]
[null,"No",1,17]
["Smoker at 53 years","Yes",7,73,0.15]
[null,"No",12,60]
[]
[null,null,"Breast Cancer developed",null,"P value"]
[null,null,"Yes (SD)","No (SD)"]
["Mean BMI (kg/m2) at 53 years",null,"27.96 (5.46)","28.15 (6.57)",0.89]
["Mean Age at Menarche (yrs)",null,"12.05 (1.18)","12.30 (1.11)",0.41]
[]
[]
["Other Cancer (Invasive) Categories","Out of 152 samples"]
["Reproductive",5]
["Other*",22]
[]
["*due to the longitudinal nature of the birth cohort, type of cancer with small n cannot be revealed as this could result in identification of individual study members"]