Will you keep your New Year's Resolutions?

According to sparkpeople.com (no, me neither), the three worst New Year's Resolutions people make are: promising to give up an unhealthy vice, aiming to lose weight, and joining a gym. (One of the best may be avoiding sparkpeople.com: the site is so eye-cracking, it can induce aneurysms. The things I do on your behalf.) None of these, according to the site, are likely to lead to a, well, successful resolution.

But how much psychological evidence supports the keeping of New Year's Resolutions (NYRs)? Are they, in the words of Wilde in The Picture of Dorian Gray, 'pure vanity' and their 'result absolutely nil'? Or are they generally adhered to? If so, what types of resolutions are kept best? And which factors, if any, make people adhere better to them? Will you succeed at pole-dancing? Will you take up darts? More importantly, will you get the shed painted?

Janus, more literally than most Roman gods, was two-faced, simultaneously looking back on the past and forward to the future. His worshippers resolved to behave, hence the custom some honour today. The earliest psychological NYR study (11- to 12-year-olds) found that children made an average of eight resolutions, with girls making more (Zeligs, 1964). Marlatt & Kaplan (1972) in the first comprehensive study of NYRs, monitored 70 students who had made resolutions (average resolution per student: 2.93), over three months.

Most people wanted to lose weight (39 per cent) with smoking cessation, and physical health/relationship changes following close behind. Twenty-five per cent of NYRs were broken within 15 weeks (more women than men reported breaking at least one). Monitoring did not increase weight loss. The most difficult to keep NYRs were related to smoking, physical health and personal behaviour. Men kept resolutions for 41 days; women, 44. Men were more likely to keep to 'stop' NYRs than 'start'; the reverse was seen in women. Thirty per cent of abandoned resolutions were self-initiated.

A larger study of 200 people found that 77 per cent kept their NYRs for a week, 55 per cent for a month, 40 per cent for six months and 19 per cent for two years (Norcross & Vangarelli, 1989), which mirrors the pattern for addiction relapse. Lack of personal control, stress and negative emotion stalled adherence.

A later study found that most people wanted to lose weight, followed by taking up exercise, then stopping smoking (Norcross et al., 2002). At six months, 46 per cent of the resolvers had stuck to their NYR. Readiness to change, self-efficacy and having the skill to change predicted adherence.

So, should we all resolve to be self-efficacious instead? Being psychologists yourselves, do you find it easier to stick to your own resolutions?

- Dr G Neil Martin is Reader and Programme Director for Psychology at Regent's University London. (@thatneilmartin). The pole-dancing is going well. This column aims to prompt discussion and debate, and the odd wry smile.