You are likely to be continuously modifying your topic throughout the research process. This depends on whether:
Broad Topic: Methodism
Narrower Topic: How did the Methodist movement begin?
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Narrow Topic: What are the fundamental beliefs of Calvinism?
Broader Topic: Calvinist theology
If you are finding too much information, your topic may be too broad. Consider narrowing it by:
Smaller piece of the topic:
If you are not finding enough information, your topic may be too narrow. Consider broadening it by: