The NHS Trust Development Authority has become concerned at the number of chairs that have resigned from the 99 trust boards it oversees, after 17 left their posts in 2013-14.

The figures – revealed in papers presented to the TDA board last week – were described as a “particular concern” because “attrition” rates of just 10 per cent are generally to be expected. Despite recent improvements, the authority admitted it struggled to recruit replacements for departed chairs.

Minutes of the TDA appointments committee in January, released only last week, said it had failed to find suitable candidates in 37 per cent of its recruitment campaigns in 2012-13.

Figures improved in late 2013-14, prompted by the TDA’s non-executive appointments team being “proactive in identifying candidates”.

The team liaised with “chief executives about local activities” and worked with “executive search companies to increase candidate awareness of the roles”. The papers said that while the use of outside agencies for recruitment was expensive, when appointments of chairs with NHS backgrounds were “already known to the TDA”, the “various companies have engaged well” with staff.

The TDA has decided it will not insist on new chairs having NHS experience, the papers also revealed. The minutes stated: “While there is clearly some value in appointing chairs with NHS experience, specifying this as a criteria would greatly restrict the pool of candidates and could in some ways be seen as undermining non-executive elements of the role.”

A recent rule change has allowed the TDA to appoint individuals to the chair role in more than one organisation.

Many trust leaders have come under increased pressure in 2013-14 as they attempted to reconcile quality and finance at their organisations, and some faced criticism from the new, tougher hospital inspection regime.

Emails leaked to HSJ in March revealed that the relationship between the then chair of Barking, Havering and Redbridge University Hospitals Trust Sir Peter Dixon and the TDA had broken down.

At Royal Cornwall Hospitals Trust two chairs resigned within eight days last July.

One trust chair, who resigned in 2013-14, told HSJ he was more surprised by the number who remained in post rather than the number which resigned.

The TDA absorbed the functions of the Appointments Commission for hiring and firing the chairs of non-foundation trusts when it was created under the Health Act 2012.