There are various approached to policy analysis and knowing your goal will help you select one that is most appropriate.  (eg. economic_ cost-benefit; effectiveness-social problem; implementations- how accurately is it carried out based on the plan for it) problem.  There are many good text that explain policy analysis methods. Try the term "framework" for policy analysis

NOTE:  Be careful with the wording. It is not human trafficking that you are analyzing: "...policy analysis on human trafficking?" it is the policy (on /for ) human trafficking that is being analyzed .  You can also say "analysis of human trafficking policy."  It sounds like you are analyzing a specific policy that is already in place?  yes?

The first thing is to establish what policies are out there and to try to create a typology of them. Then if you are look at effectiveness to see what data Governments collect -obviously crime data/volume data is a key starting point. Often there is not much. Then also an academic literature search. As the previous colleague stated the framework is key as you must define the subject, the geographical coverage and also then look at the value base of the policy. For example, policy can have a symbolic effect without actually leading to reductions in harm. Media reports are a useful source to determine this. Logical, desk based critiques of policy can also be useful if the commentator understands the subject and the main social and political dimensions involved. It is worth bearing in mind that policies often fail for very practical reasons (e.g. lack of border guards) and these factors can be analysed by looking at data and the responses of organisations like trade unions and trade associations to the policy. As previously stated I would start by using a standard framework for policy analysis that suits your personal goals. if the study is international I would also limit its geographical scope or the list of jurisdictions included. Try to make it doable!

Thank you so much. I appreciate.