## Appendix A DAG Variables  
Next, we present all the links between the variables of the DAG along with an explanation for the connection of the corresponding nodes. * Age \(\rightarrow\) Menopause: This is an obvious relationship, since age in the majority of the cases indicates whether the woman is pre-menopausal or post-menopausal. * Age \(\rightarrow\) Estrogens: According to [PERSON] [70] estrogen levels peak in the mid-to-late 20s in women and then decline by 50% by 50 years of age and dramatically decrease further after menopause. * Age \(\rightarrow\) Bone Mineral Density (BMD) loss: BMD loss increases as a person gets older [71]. * Menopause \(\rightarrow\) Aromatase Inhibitor (AI) treatment: Only post-menopausal women undergo AI treatment [72]. * Menopause \(\rightarrow\) Estrogens: Estrogen levels in post-menopausal women drop and they no longer ovulate [70]. * AI treatment \(\rightarrow\) Estrogens: AI treatment specifically targets estrogens and, thus, accelerates their deprivation [70]. * Family History (patient's ethnicity) \(\rightarrow\) Estrogens: According to [PERSON] and [PERSON] [73], there are variations in the estrogen levels of breast cancer patients among different ethnicities. * Body Mass Index (BMI) \(\rightarrow\) Estrogens: Clinicians advise was that BMI is a good indication of whether the patients have better eating and exercising behavior. * Heritage \(\rightarrow\) Estrogens: Clinicians informed us that genetics, mainly if the mother of the patient had osteoporosis or had a limb fracture, has an effect on estrogen levels, which afterwards lead to a reduction in BMD. * Estrogens \(\rightarrow\) Calcitonin: Calcitonin is proposed as mediator of estrogen action, as is mentioned in [74]. * Estrogens \(\rightarrow\) Mood: Based on [PERSON] and [PERSON] [75], a lack of estrogens worsens the patient's mood. * Estrogens \(\rightarrow\) Abdominal Fat Accumulation: Low levels of estrogens can contribute to women gaining fat in the belly area [76]. * Estrogens \(\rightarrow\) Energy/Fatigue: Clinicians informed us that a lack of estrogens lowers the patient's levels of energy and, thus, causes fatigue. * Estrogens \(\rightarrow\) Sleep quality: Clinicians highlighted that information about sleep is crucial for studying the case of osteopenia and osteoporosis. As is indicated in [PERSON] et al. [77], low estrogen levels cause sleep disturbances. * Estrogens \(\rightarrow\) Ability to concentrate: The research of [PERSON] et al. [78] suggests that estrogen levels have an impact on memory and cognition. Hence, low estrogen levels lead to difficulty in concentrating. * Estrogens \(\rightarrow\) Hot flashes: Clinicians underlined that a lack of estrogens have a negative impact on patients' hot flashes. * Estrogens \(\rightarrow\) Libido: Clinicians highlighted that a lack of estrogens decreases patients' libido. * Estrogens \(\rightarrow\) Depression: The research of [PERSON] [79] indicates that low estrogen levels are associated with depression. * Exercise \(\rightarrow\) Mood: Research of [PERSON] and [PERSON] [80] reveals that exercise leads to an improvement in mood. * Exercise \(\rightarrow\) Abdominal Fat Accumulation: Clinicians discussed that if a person does more intense exercise, then there is probability for less abdominal fat accumulation. * Exercise \(\rightarrow\) Energy/Fatigue: Intense exercise lead to fatigue, as is stated in [81]. * Exercise \(\rightarrow\) Sleep quality: The research of [PERSON] et al. [82] indicates that exercise decreases patients' sleep complaints as well as insomnia. * Exercise \(\rightarrow\) Ability to concentrate: The research of [PERSON] et al. [83] suggests that mild exercise can improve the ability to concentrate. * Exercise \(\rightarrow\) Hot flashes: The research of [PERSON] et al. [84] indicates that higher levels of physical activity are significantly associated with increasing odds of moderate or severe hot flashes.