We must not rush our part-time PhDs

I have become increasingly worried about an apparent emphasis on the time that research students take to complete their doctorates and yet more league tables citing universities' completion rates ("The slow road: where PhD success comes late, if at all", 22 July).

While this may be relevant for young doctoral students or those on full-time research grants, it is surely not so for older, professional people who wish to pursue research interests in order to improve services for clients, or to reflect on aspects of theory and practice in their disciplines in a supportive academic environment. Such students are part-time, self-funded and have to do their research while holding down demanding jobs and attending to a wide variety of family commitments.

I have had the privilege of supervising both groups, but at Goldsmiths, University of London, more of the latter - many of whom come from "non-academic" backgrounds and have worked their way through the higher education system while being employed in, for example, the NHS, social or mental health services. They now feel under extreme pressure to finish their theses prematurely, resulting in a return of the lack of confidence they often felt when starting their research.

Is there some suggestion that the length of time taken equates with the value of the final thesis, or is there a timescale that equates to a "norm"? How rigid are these timescales and should we really consider "sacking" someone who, being a bit older, might be a bit slower and need more time, or whose research has to take into account constant changes in context (such as the NHS)? I am not talking about people who are not engaging or who have problems paying fees, don't produce work and drop out, but those who work slowly, steadily and are doing original, demanding (sometimes emotionally demanding) research.

I perceive growing panic among universities about their places in such league tables: as a result they forget about the individuals and their needs. If better support mechanisms are put in place for all research students, that is excellent, but placing undue time pressure on them is not.

I am making a plea on behalf of part-time professional students. We must realistically acknowledge their life commitments. Their passion about their topics and the likelihood that they will produce valuable theses that contribute to improved public services more than justify greater flexibility.

Diane Waller OBE, Emeritus professor of art psychotherapy, London.