Based on the contents of the README and the CSV file, here are the issues identified according to the hint about unclear calculation processes in the CSV dataset file:

1. **Unclear source and methodology for the obesity and undernourishment percentages**:
   - **Issue**: The dataset includes percentages for "Obesity" and "Undernourished" for each country without clarification on how these percentages were calculated.
   - **Evidence**: Columns named "Obesity" and "Undernourished" in the CSV file.
   - **Description**: The README file does not provide details on the sources, year of data collection, or the methodology used to calculate or source the percentages for obesity and undernourishment. This lack of clarity can lead to misunderstandings about the reliability and relevance of these data points.

2. **Unclear calculation for confirmed, deaths, recovered, and active COVID-19 cases**:
   - **Issue**: The dataset contains columns for COVID-19 statistics (confirmed, deaths, recovered, and active cases) expressed as percentages without explanations of the base numbers or the date these data refer to.
   - **Evidence**: Columns named "Confirmed", "Deaths", "Recovered", and "Active" in the CSV file, all provided in percentages.
   - **Description**: The dataset does not clarify whether these percentages are relative to the total population, number of tests conducted, or another baseline. Furthermore, without referencing the specific date or time period these data represent, it is challenging to align this information with external data sources for analysis or verification purposes.

These issues point to a broader necessity for detailed documentation accompanying datasets, particularly regarding the methodology of data collection, calculation processes, and the source of raw data, to ensure transparency, reproducibility, and trustworthiness of the analysis derived from such datasets.