RECRUITMENT STRATEGIES randomised into two groups. The first

group were invited to an interview with an exercise consultant (intervention sub- jects) while the second group were sent information through the post on local exercise facilities (control subjects). Fifty seven per cent of subjects returned ques- tionnaires and of those 64% were deemed to be insufficiently active. Seven hundred and fourteen 45-74 year old low active patients were randomised. Thirty five per cent of intervention subjects actually received the intervention from the exer- cise specialist. The only significant differ- ence between attenders and non-atten- ders was age group. Those aged 55-59 were 3.5 times more likely to attend. There were no differences by gender or baseline physical activity.

Pros and cons The west London study had an additional recruitment stage, the lifestyle question- naire. Forty three per cent of subjects were lost at this stage with a further 65% of intervention subjects failing to attend for the intervention. Although the num- ber of subjects receiving the intervention was low they still represented the target group of inactive middle aged men and women. The questionnaire stage could easily be avoided if patient records held an accurate record of inactivity.

The studies utilising medical note flag- ging and direct mail both suffered to some extent as a result of the letter of

General advice ● Successful outcomes have been associated with informal home-based physical

activity of moderate intensity, usually walking, with regular support from health pro- fessionals ● Advice from a doctor to increase physical activity can have an effect but only in the short term ● The greatest health gain from increased physical activity would be achieved by targeting sedentary, middle aged men, who are also likely to be the most cost-effec- tive group with regards to intervention ● Recruitment rates are the most important variable influencing the cost-effective- ness of interventions ● Recruitment rates are higher among people already participating in some form of physical activity in their daily life ● Overweight patients appear more likely to enter schemes compared with normal weight individuals as do non-smokers compared with smokers

invitation. In both studies the invitation letters made reference to the exercise intervention, meaning that only those people who were ready and willing to change their physical activity level were likely to attend. Unpublished results from another study (the Move-It study) using similar recruitment methods shows that when the letter of invitation refers only to a health check and requires no com- mitment to change physical activity, the proportion of people actually receiving intervention can be increased by as much as 20%.

Other factors Two other factors that may affect recruit- ment rates are whether the patient is offered a specific appointment, or required to take the initiative to make the appointment themselves, and the location of the appointment.

The team in the

Move-It trial sent subjects a letter giving them an appointment date and time with a named person in the medical centre where they were registered, with the opportunity to cancel or change it if they wished. In the west London study subjects were asked to return a card indicating a preference for appointment dates and time and were seen in a local community hall. The Move-It study had a 20% higher attendance rate. Timing of appointments may also be important. Anecdotal evidence from the Move-It study suggested a preference by patients for early morning and evening appointments, particularly for working men. This is an important consideration in view of the desire to recruit this particular group.

22 SportEX

The two targeted interventions reported here showed that those aged around 55 years are more likely to accept an offer of an intervention. Targeting people as they move towards retirement could be both a cost-effective and need-based focus for physical activity promotion.

Conclusions The studies reported here show that it is possible to recruit cost-effectively those with most to gain from increased physical activity if the recruitment is targeted and does not require the time of doctors or nurses. To date, opportunistic recruitment methods have failed to recruit those with most to gain and is an expensive option compared to more proactive methods such as direct mail. Those engaged in primary care schemes should expect that the offer of an intervention will only be taken up by between 35-55% of people. In the future, if GPs computer records held a reliable measure if inactivity, recruitment of target groups would be simpler.

In practice, a targeted proactive approach to recruitment, which also allows for opportunistic recruitment, is likely to lead to the most successful recruitment strategies. It is possible that this type of recruitment can be carried out by an administrator. What is required now is more evidence regarding effective inter- ventions.

The final word Physical activity interventions using sys- tematic recruitment strategies to target those with most to gain have greater potential to maximise population health than the more usual GP referral schemes