Ken is my first patient of the morning and he is not a happy bunny. The nurse at the "fit-to-work assessment" has decided that he is in fact "fit to work" and cancelled his benefits payments. Ken is one of the 78% of people that are signed off sick but are apparently entirely capable of an honest day's work. This would suggest that I and my GP colleagues' assessments of our patients' capability to work is only correct 22% of the time. My doctor ego can just about cope with this sort of poor strike rate but I'm not sure it will ever recover from having my apparent poor assessment being corrected by a nurse! The nurse who filled in a form and ruled Ken fit to work has in a single appointment overridden the years of sick notes that I have been dishing out.

Ken is 54 years old and is the sort of person that the government desperately wants to get back in to work. He had worked as a scaffolder since leaving school at 16 but after 38 years of hard graft his shoulder gave in and he came to see me. Initially I signed him off for a week so he could rest it. That turned in to a few more weeks as I organised an X-ray and physiotherapy. By the time he had seen the orthopaedic surgeon he had been off for a few months and his company had let him go. In reality it didn't really need a specialist to tell Ken that after 38 years he wasn't really up to lugging great big tubes of metal around on his shoulders any more.

We did talk about other things Ken might do but he told me that he "wasn't the sort of bloke to work in an office". He had worked as a scaffolder and on building sites all his life and stubborn bugger that he was, he wasn't going to consider anything else. £65.45 per week isn't a lot of money but as long as Ken had his housing benefit paid and had a small amount of pocket money for beers and cigs he was prepared to take what he called early retirement. "There are no jobs out there for people like me" he would say and he is probably right. Ken is physically capable of working in an office but then if 30-year-old law graduates can't get low-paid admin work in an office, Ken had no chance. Judge me if you wish but I carried on signing Ken off and he hasn't worked for the past 3 years.

The general consensus appears to be that as a GP I am best placed to make an informed and objective decision about my patients' capability to work. The truth is that I can't make an objective decision because I have a relationship with my patients. I have known Ken and his family for years. I have seen him cry when his mum died and shared the joy of meeting his first granddaughter. We've discussed his erectile dysfunction at great length and on more than one occasion I've stuck my finger up his bum. I am not a faceless nurse working for the Department for Work and Pensions, I am his family doctor and he expects me to be on his side.

This may sound like I'm trying to defend a generation of GPs who have consistently colluded with their patients to cheat the taxpayer, but the truth is that I am the patient's advocate and without wishing to spout too much psychobabble, I probably went in to medicine partly because I wanted to be liked. It takes about 10 years to train to be a GP and costs the taxpayer lots of money. There must be better ways to spend my working day than having stand-up rows with my patients over sick notes. GPs like me who work in deprived areas spend a huge amount of their time filling in sick notes and completing incapacity benefit forms. It is dull and takes appointment time away from people who need to see a doctor because they have something wrong with their health.

I once heard of a GP in a particularly deprived part of Wales who would walk into his busy waiting room and ask all his patients who were present only for a sick note to put their hands up. He dished them all out a sick note without asking a single question and simultaneously cleared half his waiting room allowing him to concentrate on spending his morning doing some doctoring rather than being a clerk for the DWP. I don't advocate this and actually try and persuade many of my patients that working might be good for both their physical and mental health, but if a person has decided that they don't want to work it is very difficult for me to persuade them otherwise. If a patient tells me truthfully or otherwise that the severity of his back pain is 11 on a scale of 1 -10, or that his depression is so severe that during every waking minute he considers throwing himself off a bridge, it is very hard for me to try and persuade him that he is in fact fully capable of spending an eight-hour shift on the till at Morrisons.

I am still quite young and not particularly worldly but in my limited experience of life it strikes me that carrots work better than sticks. The cost of processing Ken's sick notes, incapacity forms, fitness-to-work assessments and then his appeals against the fitness-to-work decisions are massive. Ultimately, if after this entire costly process Ken was eventually forced on to jobseeker's allowance the result would be that he would be getting his £65.45 from a different department but it would still be extremely unlikely that he would end up with a job.

If it was up to me rather than trying to beat Ken into submission, I would try and offer a few carrots instead. Perhaps offer him free training to go on a fork-lift driver course. Maybe offer him an extra £20 per week on top of his benefits to do six hours per week helping out at a local community centre. Getting some self-esteem back and re-entering the world of work at some level would surely push Ken closer to leaving the benefits system than simply spending a lot of time, money and effort switching him from one handout to another and labelling him as a "benefits cheat".

• For reasons of privacy and confidentiality the author has altered certain identifying features and fictionalised some aspects of the story, but the article is intended as an honest reflection of a typical long-term sickness case