Over 2,500 readers responded from 169 prison establishments and special hospitals in England, Wales, Scotland and Northern Ireland. 2,383 questionnaires were analysed by Ascot Drummond Limited.

We asked Hilary Metcalf, a senior research fellow at the National Institute of Economic and Social Research, to comment on the findings. She told us that the survey showed "how little support for rehabilitation there is for many prisoners, particularly those on remand and serving short sentences." She noted that a third spent 18 hours a day in their cells; three out of five received no education; two out of five felt they had not gained work or education skills; and two out of three thought prison had not prepared them for their release.

" The survey tells us more about the effect of prison on drug use", said Ms Metcalf. "Over half said they had used drugs before going to prison - but one in ten who had not previously used drugs had done so in prison. Drugs were easy to get in the majority of prisons … On the other hand, prisoners who said that addiction programmes were available were twice as likely to have reduced their use of drugs."

Assessing the impact of imprisonment on personal relationships, Ms Metcalf said that "over three in five prisoners with children said that their personal relationships had been ruined. She added that "nearly half the prisoners had not seen their children for six months or more" and that "two out of five had not received a domestic visit in three months - small wonder when one third of prisoners were more than 100 miles away from their personal visitor."

Ms Metcalf also considered prisoners' replies to questions about their sentence. One in five said they were innocent whilst half of the rest felt their sentence inappropriate. Only two out of five who accepted the court judgement thought that prison had prepared them to 'lead a law-abiding and useful life on release.'