With over a million active charities in the United States, selecting organizations to support can be an overwhelming experience for many donors. The presence of too many options—without a way to meaningfully differentiate between them—can lead people to fail to choose at all. Even if donors have a manageable number of charities to choose from, selecting among those can be challenging because of uncertainty about which ones are the most worthy.

With support from the Bill & Melinda Gates Foundation, ideas42 has designed and tested GiveLists (short lists of charities organized by cause and vetted by an identified curator) as a potential solution to these psychological barriers to generosity.

Over the last two years, we’ve set out to test GiveLists in the laboratory and the real world. We’ve found that GiveLists can help donors follow through on their generosity—but developing effective lists isn’t as simple as merely narrowing down the options. Both simplification and validation are key elements of successful lists.

We distilled surprising insights from our lab research into three useful best practices that can help practitioners of charitable giving fine-tune GiveLists and help donors choose well and with confidence.

Explain how charities were selected

People report that they want more information on charities before making a donation. However, a survey showed that few follow through with their intention to do research. That means that simplifying their choice set down to a short list of organizations may not be enough to help donors feel confident that their dollars will be used effectively, because researching those organizations is still a barrier to action.

Rather, people may like to know why charities made the list. We wondered if we could overcome this barrier to action by providing donors with a signal of validation that the charities on the list met criteria important to most donors.

In a lab experiment, we found that explaining how charities made the list, specifically “charities were selected because they have a high impact,” encouraged donors to give 13% more than when offered no explanation at all. Presenting multiple criteria further boosted the average gift amount up to 18%.

Donors reported that these brief explanations reduced doubts and anticipated regret, suggesting that this signal of validation satisfied their desire for more information. The explanations of selection criteria do not need to be overly detailed. Just the simple assurance that some thought went into the selection can be enough to prompt greater confidence and generosity.

Use a generic curator

We expected specific curators, from well-known foundations to well-liked celebrities, to inspire more generosity than generic, unnamed curators (“experts in education” or “people like you”).

But when groups of participants saw the same list of charities but curated by different people or organizations—for example, we named a well-known foundation, a celebrity (specifically, David Letterman), and also the broader “people like you”—surprisingly, they donated more frequently and/or made larger gift amounts in response to the list from “people like you.” In another experiment with a similar set-up, except the list included an explanation of how the charities were selected, “an expert” inspired more people to donate than did either the well-known foundation or the well-liked celebrity.

Why would this be? One explanation is that generic curators provide a signal of validation, yet are free from loaded associations that may be attached to specific people or organizations. David Letterman shouldn’t take it too personally—it can likely happen to anyone!

Offer an option to donate to all

Paradoxically, a GiveList may make selecting a single charity more difficult since donors have to choose between similar organizations and can’t easily eliminate any because all of the charities seem worthy.

That’s why in one experiment, we included a donate-to-all button, which allows donors to donate to all the charities on the list with one click. Presenting donors with the donate-to-all button, rather than a prompt to choose one charity, increased the likelihood they would follow through on their pledges to donate by 10 percentage points.

By eliminating the need to narrow down the list to the most worthy charity, the donate-to-all button clearly simplifies the decision process. But, it also allows donors to diversify their donation among all the charities on the list, potentially freeing donors from wondering if they made the right choice or worrying that they may regret their choice in the future.

Applying these three best practices can help to maximize the impact of GiveLists and make it easier for donors to follow through on their true altruistic intentions. Notably, this research shows that the effect of GiveLists isn’t solely driven by simplifying the choice set to a manageable number of comparable charities. Signals of validation are also essential to helping donors give with confidence, and can meaningfully impact giving behavior. To learn more, stay tuned for our upcoming report that details both our lab and field research on GiveLists.

Gathering and using evidence of what works can help donors be more generous and help charities obtain the funds they need to further support critical causes that create wide-ranging public benefits across the world.