Medical statistics and data play a crucial role in understanding various aspects of healthcare and making informed decisions. While it is difficult to cover all the specific statistics and data that one should be familiar with for an exam, I can provide you with some key areas and examples that are commonly tested in medical exams. It is important to note that medical exams can vary in their content and focus, so it is always a good idea to consult your study materials and syllabus for specific topics.

1. Epidemiology Statistics:
- Incidence and prevalence rates of diseases: These statistics help in understanding the frequency of diseases in a population.
- Mortality rates: These statistics provide information about the number of deaths caused by specific diseases or conditions.
- Risk factors: Understanding the association between risk factors and diseases is important for prevention and intervention strategies.

2. Clinical Trial Data:
- Randomized controlled trials (RCTs): Familiarity with the design and interpretation of RCTs is crucial. This includes knowledge of concepts such as sample size determination, statistical significance, and confidence intervals.
- Adverse events and side effects: Being aware of the frequency and severity of adverse events associated with specific medications or interventions is important for patient safety.

3. Health Systems Data:
- Health expenditure: Understanding the financial aspects of healthcare, including government spending and private expenditure, is important for healthcare planning and policy-making.
- Health workforce statistics: Knowledge of the number of healthcare professionals (doctors, nurses, etc.) per population is crucial for evaluating healthcare capacity and workforce planning.

4. Demographic and Social Determinants of Health:
- Age and gender-specific statistics: Population demographics can influence disease patterns and healthcare needs.
- Socioeconomic status: Understanding the impact of socioeconomic factors on health outcomes is important for addressing health disparities.

In conclusion, while it is difficult to cover all the specific medical statistics and data that one should be familiar with for an exam, the areas mentioned above are commonly tested. It is important to consult your study materials and syllabus to identify the specific topics that you need to focus on for your exam.