Yet putting that information together in a meaningful way has proved to be complicated. “You’re seeking to define the most useful of material factors,” Ms. Trager said. “That is nuanced and challenging for clients to understand.”

Here is a look at four metrics that either are being introduced or have been overhauled in an effort to simplify the process for investors.

Hoping to be a one-stop shop

The Global Impact Investing Network, a nonprofit advocacy group, has operated the IRIS rating system for the past decade. It has contributed to metrics that evaluate impact investments, with the intention of creating a commonly used method, similar to the generally accepted accounting principles used by the Securities and Exchange Commission. IRIS is set to be reintroduced this month.

The new version, IRIS+, is meant to translate impact investing goals like gender equity, climate change and affordable housing into results, said Amit Bouri, the chief executive of GIIN. He said the new system would help investors know exactly which metrics to track if they hoped, for example, to bring clean energy to rural areas.

The revised IRIS system is also an acknowledgment that impact investors want more ratings they can act on, he said.

“Before, the people doing impact investing were do-gooder organizations by design,” Mr. Bouri said. “When I fast-forward to today, and I have a conversation with the chief investment officer of an investment fund or the chief executive of an asset manager, they all want to talk about impact investing. But they want to know how they can best understand their performance.”