Mental health professionals failed to carry out an in-depth assessment of a man with paranoid schizophrenia who went on to decapitate his mother, states a report released last week.

An internal review into how Leicestershire Partnership NHS Trust handled the case of Peter Andrews has found that "the delusional system Andrews developed was not subject to in-depth assessment or in-depth review".

Andrews was detained indefinitely at a psychiatric unit last month after Leicester Crown Court decided that he was unfit to stand trial for the attempted murder of his 80-year-old mother - also diagnosed with schizophrenia - in January 2003. She had died in her sleep before Andrews' attack.

He was the sole carer for his mother, but had a care worker who visited on the day of the incident and reported Andrews had greeted her in the usual manner.

The report recommends that, where someone has been diagnosed with schizophrenia and has not been admitted to hospital within three years, the need for further assessment should be considered.

Andrews, who was diagnosed with schizophrenia in 1990, had been dealt with by several consultants. Record-keeping by the community mental health team was, according to the report, "brief, lacked analysis and did not reflect the quality of the interventions offered".

Among its 20 recommendations, which are expected to be implemented by December, is the need for the trust to appoint a single care co-ordinator for cases where multiple members of a family have needs, and to closely monitor the recruitment of psychiatrists.

An independent review into the case will also be published later this year.