For three months, Chris Isles tried to recruit a locum doctor to work on his busy emergency ward. He was shocked by his findings

I work in a district hospital which, like many others around the country, is facing a shortage of doctors. Three months ago, our 150-bed medical unit which takes in emergency patients – from strokes to heart attacks – was missing a third of its complement of middle-ranking and junior doctors.

Our attempts to permanently fill these posts failed. We got responses from several apparently suitable doctors working overseas, but it would be at least three months before their paperwork would be complete to allow them to come to the UK, so they were no use for our current crisis.

There was a European doctor with no previous NHS experience who had been working on a cruise ship for the past year; a gastroenterologist whose CV stated that his knowledge of psychosomatics allowed him to treat disorders such as globus hystericus (a rare psychological swallowing disorder), but gave no clear idea that he would know what to do if faced with a patient with life-threatening haematemesis (a stomach haemorrhage).

There were many other CVs like these. Human resources tried their hardest to procure suitable locums from staffing agencies, but with no success. It was at this point that I decided to become involved in the appointment process. The cases that follow relate to a three-month period and are all true. I don't think I could have made them up if I'd tried.

Dr A: Around Christmas 2009 a medical staffing agency emailed offering "a fantastic doctor with very good UK experience". I booked him immediately. Four days later came another email: "He is not wanting to work in Scotland (too cold!!) – only wants to work in or around London." You win some, you lose some, I thought.

Dr B: The email from the agency read: "I have a very good general medicine senior house officer [a doctor with at least two years' experience on the wards] available. If he is of interest, snap him up as he won't be around for long as his CV looks brilliant." However, buried in the CV was a reference from a UK consultant. This stated that Dr B's basic skills were equivalent to a doctor who was just one year out of university. "Due to only a short period of attachment on my ward I am unable to comment about his competence in great detail," the consultant's reference read. We decided not to proceed.

Dr C: This doctor's UK experience amounted to two months as a locum senior house officer (SHO) for which no references were provided. Undeterred, the agency wrote: "I can confirm that this doctor is still available as of this point, but things change really quickly with SHOs as they seem to be in short supply!" I felt this level of enthusiasm was likely to have been misplaced, but sure enough the doctor had gone in the time it took me to say "book him".

Dr D: This European doctor was working in the UK and had reasonably good references. I decided to go ahead and wrote a nice welcoming email. The agency assured me that the booking had been accepted. Two days later I received an email from Dr D that read (word for word): "Sorry. I received your message but I do not understand about which company you are talking. I do not know anything about your hospital (that should I can go). If you can tell me more details or it is a mistake?" I phoned the agency to ask for an explanation but no one was able to provide me with one.

Dr E: This doctor was offered to us as an SHO. We booked him but our human resources department subsequently discovered that he had only a student visa and was not even licensed to work as a doctor in this country. We did not take him on. The agency wrote to us later to say that because the doctor had not acted professionally with their staff and had not provided them with information they had requested, they would be taking him off their books. Because agencies do not share information about doctors who behave unprofessionally with other agencies, this doctor will presumably have no difficulty signing up elsewhere.

Dr F: This doctor had trained for many years overseas but wanted to move to the UK. The agency offered the doctor to us as an SHO, and his CV said that he had worked at this grade in another UK hospital. The reference stated that the doctor was very reliable and showed very good timekeeping, clinical and communication skills, and enjoyed good relationships with patients and colleagues. But he looked so terrified on arrival that we felt we had to employ another doctor to cover for him when he was supposed to be responsible for emergency admissions. It soon became apparent that Dr F's comfort zone was near that of a final-year medical student. We ended the contract. I tried to persuade the doctor and the agency that he would be better off accepting a clinical attachment at a hospital and then apply for a junior doctor's job before considering a more demanding role. The agency had already offered him another SHO locum.

Dr G: One of our core medical trainees decided to relinquish her post for personal reasons just as she was due to start a three-week stint assessing acutely ill patients when they first arrive at the hospital. We advertised for a locum to cover her first weekend but no one materialised. Then, with three or four days to go, we received word that a doctor working as a consultant overseas would cover the three 12-hour shifts, provided we paid over the odds. We duly did so. There were no complaints during the first two nights on call, but on the third night the doctor was found asleep in the doctors' mess. The doctor with whom the locum was on call asked for help with a difficult patient but was told that the locum was "too tired" to assist. One of the staff nurses filed a critical incident report over the locum's handling of another case. I sent both complaints to the agency, which forwarded them to the locum for comment, but we have heard nothing since.

Dr H: The agency said this doctor was looking for a full-time post. The doctor's referee stated: "I have found Dr H as an honest dedicated and conscientious doctor who is keen to provide excellent care in all settings. [Dr H] has good communication skills and provided administrative support on an NHS ward setting in the last six months. [Dr H] is happy to work within general medicine, ENT [ear, nose, and throat], and general surgery." When we asked the agency for more details of Dr H's experience we were told that Dr H had spent the last six months working as an administrative ward clerk – a clerical job that needed no medical experience at all.

Dr I: We were offered this specialty registrar (SpR – a senior doctor just below the rank of consultant) at the eye-wateringly high rate of £70 a hour, plus tax. This was sanctioned because we were so short of staff. The doctor's only UK experience had been as "locum SpR" for six weeks in another district general hospital. I spoke to one of the consultants at this hospital, who said the locum was functioning as a doctor with between one and two years' experience. He said he never asked the doctor to do any medical receiving as he felt this would be "asking for trouble".

Dr J: I got an email from an agency offering, "a VERY good SHO in general medicine". I phoned the agency to ask if this doctor was capable of undertaking medical clinics and receiving acute cases, to which they said, "I can ask". If they did not know, should they be advertising him? The reference looked satisfactory so I emailed back saying we should book him. An hour later I received another email: "Just spoke to the doctor, other agencies looking to book him. But Dr J would like to work at your trust. He wants to know what shifts he will be working and how many hours. He would like as many on-calls as possible." For "locum agency" read "cattle market", with locums going to the highest bidder.

I have spent three months trying to fill our middle-grade rota without success. A huge amount of time has been wasted attempting to book doctors with little experience of working in the UK, whose competencies I have been unable to assess, who did not always have the right paperwork and who could break an agreement at will and without repercussion.

I believe the responsibility for this lies with the European Working Time Directive and Modernising Medical Careers, which have created a health service in which we are forced to rely so heavily on locums. But most of all I rage at the locum agencies whose failure to regulate themselves should have led to intervention by the GMC by now. We pay lip-service to patient safety by allowing this scandalous state of affairs to continue.

Professor Chris Isles is a consultant at Dumfries and Galloway Royal Infirmary. A version of this article appears in this week's British Medical Journal

The locum problem...

Concern about stand-in doctors was highlighted when out-of-hours locum GP Daniel Ubani killed a Cambridgeshire pensioner by injecting him with 10 times the recommended daily dose of diamorphine in 2008.

In spite of the problems, demand for such agency locum doctors has increased as the ability of agencies to meet requests has fallen. This has been fuelled by the full implementation of the European Working Time Directive for doctors. The agencies' ability to meet this demand has fallen from 83 per cent of all requests filled in 2006-07 to 71 per cent in 2008-09. Consequently, hourly rates for locums are high. Audit Scotland found pay rates ranged from £34 to £87 an hour, excluding VAT.

Employment agencies are supposed to vet locum staff, but NHS boards are also responsible for making sure that pre-employment checks are carried out. Because these arrangements are not always formalised, there is a risk that checks may not be completed. Feedback on performance is often verbal, rather than written. This means poor performance isn't always fed back to the agencies.