PERFORMANCE: A large teaching hospital may have to assess thousands of patients for clinical harm after an investigation found its data systems could not guarantee people had been treated.

St George’s University Hospitals Foundation Trust in south west London said it was investigating and was assessing whether patients had come to harm as a result.

A report sent to the trust’s July board meeting said: “The [trust was] assured there were no patient safety issues or risk to patients which had not already been identified.” It did not say what the identified risks were.

The trust said it was taking “urgent action to stabilise the risk” and had suspended reporting to the national data collection.

The report found cases of “planned patients that do not appear to be managed”; “patients excluded inappropriately across admitted and non-admitted pathways”; and a “significant number” of cases where it was not clear how long patients had waited.

A trust spokesman said it was not sure how far back the problems went or how many patients would need to be assessed for harm.

St George’s performs 28,400 elective and day case procedures a year and books approximately 637,000 outpatient appointments.

Chief operating officer Corinne Siddall said in the board report that 65 patients had required “in-depth review” and 63 had subsequently been treated.

In a statement, interim chair Sir David Henshaw and interim chief executive Simon Mackenzie said: “Earlier this year, we became concerned about the quality and robustness of our RTT data reporting.”

However, Ms Siddall’s report on the issue in the trust’s May risk register said the issue had been flagged in May 2014.

The board risk document from May 2014 said there was a “risk to patient experience of 40-plus week waits for surgery.”

The most recent risk report on the issue said there were “specific issues regarding cardiothoracic surgery waiting lists in particular”.

The trust has seen considerable turnover of senior staff since 2014.

St George’s has extended its review of the data to see if cancer patients who were due to start treatment had been missed out.

Performance against the 92 per cent referral to treatment target was 88.3 per cent. Six patients have waited more than a year for treatment.

The trust has also appointed a director of quality governance who started in July.