Treating obesity: a follow-up study. Can the stages of change model be used as a postal screening tool?

We have previously shown that although a postal questionnaire based on the stages of change model (SCQ) failed to distinguish outpatients most likely to lose weight, it appeared to influence attendance rates. We therefore audited attendance upon receiving a pre-appointment SCQ in the post and compared this to previous standard practice in 1996.

Seventy-eight obese outpatients (BMI 36.7 +/- 6.7 kg m-2, age 43 +/- 15 years) (mean +/- SD) were included. Twenty-nine per cent of patients failed to return an SCQ and were not sent an appointment and therefore did not block dietetic time. Eleven per cent returned an SCQ but did not attend (DNA) visit 1, whilst 21% attended visit 1 but DNA visit 2. Thirty-nine per cent attended both appointments and lost a significant amount of weight (105 +/- 23 vs. 103.2 +/- 23 kg, P < 0.0001) in 4 weeks. There was no difference in SCQ results between groups. Overall attendance rate at initial and follow-up appointments increased by 11%, while DNA rates fell by 20% compared with the 1996 audit.

The SCQ has sifted out one in four patients who previously DNA an initial dietetic outpatient appointment. This has reduced waiting-list time as appointments are only book on return on the SCQ form, increased effective use of dietetic time through increased attendance rates, and lowered the DNA rate of follow-up appointments.