Introduction

Top Abstract Introduction Subjects and methods Results Discussion References

Non-attendance for hospital outpatient appointments, both new and follow up, is about 12% nationally.¹ The cost per lost appointment during 1984 ranged from £20 to £50.² In 1997 it had risen to £65.³ An estimated total cost to the NHS is £300 million annually.¹ Non-attendance increases waiting lists.⁴ Non-attendance is unrelated to the seriousness of the illness,⁵ and patients who do not attend may have treatable morbidity.⁶ The duration of new appointments is usually longer than follow up appointments⁷ making non-attendance for new appointments more wasteful.

There are several reasons for non-attendance including illness and work commitments. ^{8 9} Patients may forget their appointment, ^{10 11} but others make a conscious decision to miss it, balancing perceived benefits and costs. ^{12 13} The main hospital factor is inadequate communication. ^{10 11 14} Two studies looked at the provision of information to the patient by the referrer, and showed increased attendance of informed patients. ^{5 15} Another study suggested non-attendance might be an indicator of inadequate communication between the patient and the referring doctor.⁹

Strategies to reduce non-attendance have previously been hospital based. Reminders alone can reduce non-attendance by 23%.¹⁶ Letting the patient make the outpatient appointment can reduce non-attendance by 30% to 50%.¹⁷ Larger reductions of 60%¹⁸ and 82%¹⁹ have been achieved by requesting that patients confirm their attendance by reply paid letter, and then telephoning those that do not reply. Non-attendance can be partially compensated for by overbooking but, if all patients attend, the clinic staff are pressurised. The increased waiting time is also unpopular with patients.²⁰

Extending the concept of sharing information between referrer and patient, we hypothesised that sending patients a copy of their referral letter might reduce non-attendance. A pilot study²¹ established the acceptability of the process and showed a non-significant reduction in non-attendance.

	Subjects and methods

Top Abstract Introduction Subjects and methods Results Discussion References

We conducted a blinded randomised controlled study, with randomisation at the level of the individual patient. Our sample size was calculated with 750 referrals in the intervention group and 750 controls: assuming a non-attendance rate of 6% in controls (as shown by the pilot study and from reviewing available data for Exeter) and 3% in the intervention group, this provided 80% power of detecting a significant difference at the 5% level. The study was approved by the local research ethics committee.

All 71 general practitioners in Exeter city, except one on sabbatical and one of the authors (WH), were invited to participate. Overall, 44 showed an interest of whom 26, representing 13 of the 19 practices, were selected using a random numbers table. Data on their fundholding status, hours worked, sex, and qualifications were available from the North and East Devon Health Authority.

Enrolment of patients
All patients referred to consultants in the two local trusts between January and May 1997 were eligible. Exclusion criteria were: termination of pregnancy; referral letters which might distress the patient; and inability to read. We recorded the reasons for exclusion. The doctors dictated the referral letters, stating if the referral was to be excluded. After typing the letter, the secretary was permitted, before randomisation, to check with the doctor that the referral was included. The randomisation was computer generated, and a numbered sealed envelope allocated the patient to receive a copy of their referral letter (copy group) or not (control group). The secretaries were instructed to enter all referral letters, other than those excluded by the doctors, to ensure all eligible referrals were included. This resulted in some letters being entered into the randomisation process which were ineligible as they were not referrals to local NHS consultants. We did not allow exclusions after randomisation in the studythat is, where a doctor decided not to send a copy after allocation to the copy group. Those that did occur were identified by retrieving envelopes after the study, and were added to the copy group for analysis by intention to treat.

Outcome measures
The main outcome measure was the number of non-attendances at new outpatient appointments, either as a first time non-attendance or non-attendance at a rearranged appointment. We monitored attendances by two methods.

Statistical methods
We used a ² test to compare attendance outcomes, Student's t tests to compare the means of continuous variables, and a Mann-Whitney U test for non-parametric data.

	Results

Top Abstract Introduction Subjects and methods Results Discussion References

Recruitment of doctors and enrolment of referrals
The 26 doctors included in our study were representative of the 71 Exeter doctors for fundholding status, hours worked, sex, and membership of the Royal College of General Practitioners. Overall, 2329 referral letters were dictated of which 251 were ineligible (not local NHS consultant referrals) leaving 2078 eligible (see website). The doctors excluded 117 (5.6%) before randomisation owing to termination of pregnancy,¹⁷ inability to read,⁸ potentially serious illness,37 sensitive conditions,29 previous suboptimal care,³ or the patient's attitude or lifestyle.30 Some had more than one reason.

Attendance rates
The doctors' records contained attendance data for all 1857 patients given an appointment. Corroborating hospital data were available for 1487 (80%). In seven instances a letter in the records described the outpatient consultation, of whom three were recorded by the hospital as non-attenders and four as having cancelled. These patients were classified as attenders. Table 3 shows the attendance data. There was no difference in non-attendance rates between the copy and control groups: 5.5% and 5.3% respectively (²=3.2, P=0.36). Overall, four of the 111 patients (3.6%) excluded from randomisation failed to attend. Non-attendance rates for patients of all Exeter doctors, from the hospital dataset, remained stable throughout the study with no difference between study and non-study doctors (data not shown).

	Discussion

Top Abstract Introduction Subjects and methods Results Discussion References

This is the largest prospective study of non-attendance at outpatient departments. The results do not support the hypothesis that sending patients a copy of their referral letter reduces non-attendance, despite earlier work suggesting that this might be so. ^{5 15 21} The suggestion that non-attendance reflects inadequate communication between doctor and patient⁹ is not supported by the results. The study shows the importance of performing a full randomised controlled trial rather than relying on impressions from underpowered pilot studies. The non-attendance rate of 5.3% is low compared with previous studies, ^{5 7 10 11 22} but was similar to non-study doctors concurrently. The patients excluded from the randomisation cannot explain this; there were few, and they had a low non-attendance rate, probably reflecting the conditions that led to their exclusion from randomisation. Nor can the seven mismatches between the attendance record in the doctor notes and the hospital data fully explain the low recorded non-attendance rate. The doctor record was used as the gold standard, in that a consultant's reply letter is unequivocal evidence of attendance, whereas other studies quote hospital data, ^{1 17} which will contain these small inaccuracies.

Possible effects of a copy letter
A referral letter may not contain the information that a patient needs to decide if attendance is worthwhile; conversely, it may inform some patients such that they consider attendance unnecessary. In the case of a referral made primarily for reassurance, the copy letter alone may provide this. Although such reassurance might decrease attendance, this effect should increase cancellations rather than non-attendances. It is possible two effects are operating, in different directions: increased attendance (in those whose understanding of their conditionand thus the need for an appointmentis improved) and increased non-attendance (in those reassured by the letter who decide not to attend). On the other hand, it may simply be that any effect of the copy letter is lost by the time of the appointment, on average 10 weeks later. A copy may have to be sent nearer to the time of the appointment to be effective.