Some people who joined Northern Ireland's neighbourhood watch schemes initially faced hostility for co-operating with police, a report said.
A number of residents were hard to reach while areas with a strong republican background may also be less favourable towards the community initiative, research for the Policing Board with a small sample showed.
Most who lived within a neighbourhood watch area (86%) felt very or quite safe in their local community and almost all schemes reported that crime and antisocial behaviour had decreased, the study said. They enhanced the relationship between the police, community and other partners and generated greater levels of community spirit.
The document said: "Some schemes felt that their relationship with the police and their scheme initially created hostility in the community towards the members and in particular the co-ordinators.
"This draws from the stereotype whereby some people might consider neighbourhood watch members to be 'snitches' or 'touts'.
"This is also seen as a barrier to growth for some schemes, especially those in areas where there are members of the community who may not want their activities monitored."
A total of 309 residents took a survey for the board and there were 428 responses from a separate piece of work involving scheme co-ordinators and others involved.
The report said: "Co-ordinators acknowledge that there can be some residents who are hard to reach and are not interested in participating in neighbourhood watch. In a number of areas such as those with a strong republican background or where there are organised antisocial activities, there are residents who are not in favour of the neighbourhood watch scheme."
Almost all schemes reported crime and antisocial behaviour had decreased since it had been in operation. A small number from urban areas reported that crime and the fear of crime was still an issue despite the presence of neighbourhood watch.
Justice Minister David Ford said it was an excellent concept, adding: "The scheme enables the building of relationships between communities, the police and other key agencies to tackle crime, anti-social behaviour and the fear of crime. Its contribution to community safety has been highlighted by this research and I welcome the fact that respondents have found it to be helpful."