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Big Brothers Big Sisters’ one-to-one youth mentoring has been shown to have a significant and positive impact on the lives of children, according to the first-ever nationwide impact study of a mentoring organization.


During 1992 and 1993, Public/Private Ventures, a Philadelphia-based national research organization, looked at 959 boys and girls, ages 10 to 16, through Big Brothers Big Sisters agencies in Phoenix, AZ; Wichita, KS; Minneapolis, MN; Rochester, NY; Columbus, OH; Philadelphia, PA; and Houston & San Antonio, TX. The agencies were selected for their large size and geographic diversity.

Of the young people taking part in the study, more than 60 percent were boys, and more than 50 percent were minorities. Most came from low-income households, and many lived in families with histories of substance abuse and/or domestic violence.

Approximately one-half of the children were matched with a Big Brother or Big Sister. The others were assigned to a waiting list (control group). The children were randomly assigned to one group or the other.

The matched children met with their Big Brothers or Big Sisters about three times a month for an average of one year.

Researchers interviewed the Littles, the children who were not matched, and their parents on two occasions: when they first applied for a Big Brother or Big Sister, and again 18 months later.


Researchers found that after 18 months of spending time with their Bigs, the Little Brothers and Little Sisters were:

  • 46% less likely to begin using illegal drugs

  • 27% less likely to begin using alcohol

  • 52% less likely to skip school

  • 37% less likely to skip a class

  • 33% less likely to hit someone

  • More confident of their performance in schoolwork

  • Getting along better with their families*

Big Brothers Big Sisters volunteers had the greatest impact in the area of alcohol and substance abuse prevention. For every 100 youth between ages 10 and 16 who start using drugs, the study found, only 54 similar youth who are matched with a Big will start using drugs. Minority boys and girls were the most strongly influenced; they were 70 percent less likely than their peers to initiate drug use.

“We have known all along that Big Brothers Big Sisters’ mentoring has a long-lasting, positive effect on children’s confidence, grades, and social skills, and the results of this impact study scientifically confirm that belief."

Judy Vredenburgh

Former Big Brothers Big Sisters President and CEO

“These dramatic findings are very good news, particularly at a time when many people contend that ‘nothing works’ in reaching teenagers,” Public/Private Ventures President Gary Walker added. “This program suggests a strategy the country can build on to make a difference, especially for youth in single-parent families.”


According to the research, these one-to-one matches are such a powerful force for influencing children’s behavior because of Big Brothers Big Sisters’ signature approach to mentoring.

A Big Brothers Big Sisters’ match is carefully administered and supported by rigorous standards and trained personnel. Professional agency staff strive for matches that are not only safe and well suited to each child’s needs, but also harmonious and built to last. That is why so much care is taken in screening and orienting volunteers, and then in matching them with children.

However, Big Brothers Big Sisters professionals are much more than just “matchmakers.” They provide ongoing support and supervision to the Big, the Little, and the Little’s family. They offer training and advice to help ensure that the match is satisfying and fulfilling for everyone involved.

Additionally, every Big Brothers Big Sisters agency subscribes to a uniform set of standards and procedures. They also receive ongoing training and consultation from the Big Brothers Big Sisters national office.

It is this web of support that helps maximize the likelihood that a Big Brothers Big Sisters relationship will “take root” and flourish. The research found, for example, that Big Brothers Big Sisters’ matches consistently spend more time together, and continue as a match for longer periods, than do their peers in other mentoring programs Public/Private Ventures has studied.

“In mentoring programs without this infrastructure, we have found that relationships evaporate too soon for effects to be possible,” said Walker.


The research found that Big Brothers Big Sisters offers a positive, broad-based program “that focuses less on specific problems after they occur, and more on meeting youths’ most basic developmental needs.”

The matches that were observed in the study shared everyday activities: eating out, playing sports or attending sports events, going to movies, sightseeing, doing chores, and just hanging out together.

What mattered to the children was not the activities, but the fact that they had a caring adult in their lives. Because they had someone to confide in and to look up to, they were, in turn, doing better in school and at home. The Littles were also avoiding violence and substance abuse at a pivotal time in their lives when even small changes in behavior or choices made can change the course of their future.

“The quality of the relationships Big Brothers Big Sisters has fostered for 100 years is the real strength behind our success,” said Vredenburgh. “Our volunteers are one of our most important assets. They make a tremendous commitment to their Littles, and now, we can point to this impact study and say, ‘See, you are making a huge difference in the life of a child.’

“When Little Brothers and Little Sisters feel good about themselves, they positively impact their friends and families, their schools, and their communities. And as this important study has shown, these young people believe in themselves because a Big Brother or Big Sister believed in them.”

Judy Vredenburgh

Former Big Brothers Big Sisters President and CEO

Making a Difference: An Impact Study of Big Brothers Big Sisters (1995) was the culmination of a four-part series on Big Brothers Big Sisters. The first three reports were A Study of Program Practices (1993); A Study of Volunteer Recruitment and Screening (1994); and Building Relationships with Youth in Program Settings (1995).

Public/Private Ventures, a national research organization with more than 20 years of experience in studying child development and social service issues, conducted independent research.

The study was funded by a $2 million grant from the Lilly Endowment, the Commonwealth Fund, the Pew Charitable Trusts, and an anonymous donor.

* Tierney, J.P., Grossman, J.B., and Resch, N.L. (1995)  Making a Difference: An Impact Study of Big Brothers Big Sisters. Philadelphia: Public/Private Ventures

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