As the credit risk manager for a private wealth management firm, you are tasked with developing a comprehensive risk management framework to assess and mitigate credit risk for a portfolio that includes various fixed-income securities. Recently, concerns have arisen regarding the potential for increased credit defaults due to economic uncertainties and external shocks, such as interest rate hikes and geopolitical tensions.

In your essay, address the following points:

1. Discuss the key factors that should be considered in assessing credit risk for fixed-income securities.
2. Describe the specific methodologies and tools that can be employed to evaluate the creditworthiness of issuers.
3. Explain how you would incorporate macroeconomic factors and stress testing into your credit risk management framework.
4. Provide a summary of potential strategies that can be employed to mitigate credit risk within the investment portfolio.