OSAKA — At train stations, parks and other public places, groups of volunteers are out in force, collecting donations for survivors of the Tohoku earthquake and tsunami. Holding cardboard boxes, they call out to passersby to open their wallets and donate what they can, and thank them with a deep bow if they drop in money.

But with more such groups than ever, many of those thinking of sending money are asking whether their donation will actually be used for the disaster victims, or end up being spent on that group's office supplies. Allegations that large groups in particular are not passing all of the donated money on to the victims but are keeping certain amounts for operating expenses are concerning potential donors.

"I want to donate, but who do I give money to, and how do I ensure all of it will really go to the victims as promised?" asked Yuko Horie, 22, a student in Nara who said she was concerned about large organizations in particular, after reading on various blogs and websites that they kept a portion of donations for their own use.