Women:
In our study, women representation was similar to their share in the disease population with respect to hypercholesterolemia trial (53 %). According to the 2019 AHA statistical update, among persons in the US with high cholesterol level (including TC > 200 mg/dl, TC > 240/dl and LDL > 130/dl), women comprised 52 to 57 % of the population. \cite{Benjamin_2019}. Globally, there was not much difference between  two sexes in prevalence \cite{20152016}. A report based on the NHANES survey 1999-2000 showed dyslipidemia was more prevalent among diabetic females than males (71 % of males had LDL above goal compared to 79 % in females)  \cite{Jacobs_2005}.  Women in this population was underrepresented in our study with only 37 % participation.  In women with ACS and stable CAD, the representation was 21 % and 22 % respectively, while the disease prevalence among women in the US population was 41 % and 48 % respectively. Globally women make up 48 % of the CAD population. 
One hypothesis for under-representation is that inclusion and exclusion criteria disproportionately exclude women. Another theory is that the number of women actually referred for screening is in itself quite low. Data suggests that women are less likely to consider participation in clinical trials, and are also less likely to be screened for trials, the reasons for both still unclear. \cite{Scott_2018}. Melloni et al. in their meta-analysis noted that women were more likely to be included in primary prevention than in secondary prevention trials, which was similar to our results. Some of the explanations were that higher-risk women could be less willing to participate in trials, that physicians may have biases in screening them for inclusion, or that there are other social or medical reasons that make their participation difficult \cite{Melloni_2010} The age differential may also have played a role in women's exclusion women are typically affected by heart disease 10 to 15 years later than men.