This link will bring you to a Portland Business Journal "article" with a focus on board diversity. In general there are a few helpful considerations on diversifying a nonprofit board from an organization's paid and volunteer leaders. One item most interesting to me was the recruiting of a DEI board officer and giving a stipend for that position.
The article title is "Building a better board: Nonprofits must embrace diversity to be effective". I fully embrace the goals of diversifying boards particularly with recruiting consumers or folks who have the "lived experience" that is the focus of the nonprofit. And maybe, this action with this target audience does make for "effectiveness" but I would offer that recruitment alone or diversifying alone does not inherently make a board effective. Much more work must be done on all fronts beyond changing who is at the table.
That said, check-out the article - helpful insights.