Waiting times: monitoring the total postreferral waitBMJ 1994; 309 doi: https://doi.org/10.1136/bmj.309.6954.593 (Published 03 September 1994) Cite this as: BMJ 1994;309:593
- T Smith
- Correspondence to: 131 Roundhill Road, St Andrews, Fife, KY16 8HG.
- Accepted 20 May 1994
Objective : To determine whether the period spent on the true inpatient waiting list is a valid indication of the total time that patients have to wait for an operation; and to assess the feasibility of monitoring the total “postreferral waiting time” by using existing computerised information systems.
Setting : Three randomly selected Scottish hospitals.
Subjects : Waiting list patients admitted to hospital for operations during June to August 1993 in six major specialties, separate attention being focused on cataract operations and hip and knee replacements.
Main outcome measure : The total time that patients have to wait for an operation after the initial general practitioner referral - the postreferral waiting time - compared with that spent at the final stage of the process on the true inpatient waiting list.
Results : In the specialties investigated roughly half (58 days; 53%) of the average postreferral wait of 110 days was spent on the true inpatient waiting list, one third (35 days; 32%) being spent on the outpatient waiting list and one sixth (17 days; 15%) waiting between waiting lists. Only a quarter of cataract patients (73/292) were treated within three months of general practitioner referral compared with over three quarters (228/292) within three months of being placed on the inpatient waiting list. Nevertheless, within a year over 99% of patients (290) had been treated whichever date was taken as the starting point.
Conclusions : Monitoring posterferral waiting times would provide a much more accurate picture for purchasers and patients of waiting times for treatment than is obtained by focusing exclusively on the true inpatient waiting list and facilitate fairer comparisons between NHS trusts in national league tables. Stringent national and local monitoring is essential to ensure (a) that future reductions in the time waiting on true inpatient waiting lists are not gained at the expense of longer periods waiting to be placed on the lists, and (b) that no increases occur in the number of patients placed instead on deferred waiting lists or exempted from the normal maximum waiting time guarantees.
On average roughly half the time waiting for inpatient treatment is spent waiting on the inpatient waiting list
Of the remaining time, one third is spent waiting on the outpatient waiting list and the rest waiting between lists
The postreferral waiting time - which refers to the period between referral by the GP to a consultant outpatient clinic and admission for treatment - is a more accurate measure of the waiting time
In three Scottish hospitals there was a two-fold variation among consultants in postreferral waiting times for cataract operations and a threefold variation in the time spent waiting on the true inpatient waiting list
Careful monitoring is required to ensure that deferred patients are treated as soon as possible after the reason for deferral no longer exists
Where guarantee exception codes are employed, as in Scotland, they should be used sparingly
The patient's charter1 has led to health authorities being required to set maximum inpatient waiting times for individual specialties and also to set guaranteed maximum waiting times for certain procedures. Three of these in Scotland - hip replacements, knee replacements, and cataract operations - have been specified nationally. As part of the monitoring process NHS trust and health authority league tables based on a snapshot of the number of patients on the inpatient waiting list - known in Scotland as the true inpatient waiting list - are published at the end of each quarter. These show the number waiting in each specialty for specified time intervals and thus the number who have exceeded the guaranteed maximum waiting time for that specialty.2, 3
The aim of this study was, firstly, to determine whether the time spent on the inpatient waiting list gives a valid indication of how long NHS patients have to wait for treatment and, with reference to Scotland, how many patients are placed instead on the deferred waiting list or are exempted from the normal guarantees. Placing patients on the deferred waiting list means that their waiting times are not counted in the national monitoring process. The second aim was to determine the feasibility of measuring (by using existing NHS computerised information systems) the total time that patients have to wait between the initial general practitioner referral for an outpatient appointment and admission for treatment. I refer to this as the postreferral waiting time. The third aim was to assess the advantages of the postreferral waiting time over the currently used true inpatient waiting time as a monitoring and decision making tool for general practitioner and health authority purchasers.
There are three types of waiting list in Scotland. These are the true waiting list, the deferred waiting list, and the repeat waiting list. The deferred waiting list is for patients who are under social or medical constraints, such as business trips or the need to lose weight, which affect their ability to accept an admission data when offered and for those who fail to attend after being offered an admission date.4 Once placed on the deferred waiting list patients must remain on it until they are admitted. In England there is no deferred waiting list as such. Patients who cannot accept an offered admission date are said to be self deferred and returned to the bottom of the inpatient waiting list. The introduction of a system for counting medically deferred patients is planned soon.
In Scotland patients on the true inpatient waiting list may also be allocated a guarantee exception code. This indicates that the normal guaranteed maximum wait for the specialty does not apply to them because their condition is of low medical priority. Traditionally this device has been mainly applied to patients awaiting tattoo removals. Providers now, however, can extend its use to other groups, including patients whom general practitioners refer to named consultants rather than to colleagues of the consultants with lower workloads. The Scottish Office proposes to exclude exempted patients from published figures soon. In England the usual procedure is for low priority patients not to be placed on any waiting list.
The precise point at which patients who are not immediately ready for an operation because of the condition itself-for example, those whose cataract is not fully “ripe” - are placed on a waiting list varies widely among consultants and hospitals throughout the United Kingdom. Patients waiting to be placed on an inpatient waiting list after having been seen at an outpatient clinic are not currently monitored.
There is also a planned repeat waiting list for patients whose care is planned over a series of admissions, an obvious example being for chemotherapy. Parallel systems to those described above also exist for day case waiting lists.
The essential dates required for monitoring postreferral waiting times retrospectively are those on which the general practitioner referral letter was received at the outpatient clinic and the date of admission. For continuous monitoring the date of referral and the current date are needed. Finding a single database containing both dates, however, is surprisingly difficult and linkage of databases is usually necessary to obtain the required data.
The main sources of retrospective data are the outpatient record (standard morbidity record 0), introduced in Scotland in April 1991, which currently records information on first attendances at outpatient clinics, and the inpatient and day case record summary sheet, known in Scotland as the standard morbidity record 1. Records from both schemes relating to three randomly selected Scottish general hospitals were obtained on floppy disk from the Information and Statistics Division of the Common Services Agency for the NHS in Scotland, loaded on to a microcomputer, and analysed with standard commercial software (dBase, IV and Microsoft Excel). Personal identifiers other than the patient's community health index number and consultant code number were removed from the research file and care taken at all stages to conform to the principles of the Data Protection Act 1984.
Records of patients admitted to hospital for operations in general surgery, orthopaedics, urology, otolaryngology, ophthalmology, and gynaecology during June to August 1993 were selected from the inpatient file including the admission date. These were linked as described5 on the basis of the patient's community health index number (a personal health service identifier in use throughout most of Scotland) to the outpatient file to determine the date on which the general practitioner referral letter was received at the outpatient clinic. From this the postreferral waiting time was calculated. A similar process yielded postreferral waiting times for hip replacements (OPCS-4 codes, W37*, W38*, W39*), knee replacements (W41*, W42*, W43*), and cataract operations (C71* to C75*).
The information obtained by this method was retrospective - that is, it depended on the patient having been admitted to hospital. The number of patients currently on the inpatient waiting lists at the end of each month was obtained from the Scottish standard morbidity record 3 scheme, equivalent to the English Korner KH07 scheme.
In the six specialties investigated about half (58 days; 53%) of the average 110 days that patients had to wait between the general practitioner referral letter being received at the outpatient clinic and hospital admission - that is, the postreferral waiting time - was spent on the true inpatient waiting list. Of the remainder, around one third (35 days; 32% - from 27% in otolaryngology and general surgery to 43% in orthopaedics) was spent on the outpatient waiting list and one sixth (17 days; 15% - from 10% to 18%) waiting between lists (figure 1; table I). The averages concealed wide variations in waiting times - for example, 25% of patients (954/3817) having postreferral waits of less than two months but 7% (267) having waits of eight months or longer. Overall there was little positive or negative correlation between the time spent on the outpatient and inpatient waiting lists (r=0.105).
Current end of period monitoring
No patient on the true waiting lists of the six specialties during the study period had guarantee exceptions. Following Scottish Office advice in December 1993 that guarantee exceptions should be used when applicable, the overall proportion rose at the end of January 1994 to 1.2% (28) of patients on the true inpatient waiting lists for these specialties.
On 30 June 1992, 14.9% of 6417 patients on inpatient waiting lists in all specialties in the three hospitals studied were on the deferred list. By the end of June 1993 the total number waiting had fallen to 4539 with the proportion on the deferred list remaining virtually unchanged (14.7%). Figures for the whole of Scotland, however, showed a small increase in deferred patients over the same period - from 13.0% (of 74 401) to 15.5% (of 71 491).2
Of the average postreferral waiting time of 144 days for a cataract operation, 53% (76 days) had been spent on the true inpatient waiting list, 25% (36 days) on the outpatient list, and 22% (32 days) waiting between waiting lists (table II).
Even when the outpatient referral date was taken as the starting point, rather than the date placed on the true inpatient waiting list, 99% of the patients admitted (290) had been waiting for less than a year (table III). This emphasises that setting guaranteed maximum waiting times based on the postreferral wait is realistic.
Average waits on the true inpatient waiting list showed a threefold variation among consultants (table IV). But when the total postreferral wait was taken into account the difference was much less pronounced, long waits on the inpatient list tending to be associated with shorter waits before being added to the list and vice versa.
Fifteen per cent (34) of the 225 patients waiting for an inpatient cataract operation in the hospitals were currently on the deferred list.
Similarly, less than half of the average postreferral waiting time of 163 days for a hip replacement and 200 days for a knee replacement was spent on the true inpatient waiting list (45% (74 days) and 48% (95 days) respectively). Around 40% of the time (66 days and 82 days) was spent waiting for the initial outpatient appointment and 13% (23 days for each operation) between lists. There was considerable variation depending on whether the patient was placed on the inpatient list at the first outpatient appointment or not (table V). Ten per cent of patients (14/141) waiting for hip and knee replacements in the three hospitals were currently on deferred lists.
Recent years have seen a substantial improvement in inpatient waiting times. As a result patients now often spend longer waiting to be placed on an inpatient waiting list than they spend on the list itself.
The monitoring and subsequent publication of postreferral waiting times as proposed in this paper would therefore give a considerably more accurate picture for general practitioners, health authorities, and other purchasers of the total length of time that their patients have to wait for treatment than is obtained by focusing exclusively on the true inpatient waiting list. It would also facilitate fairer comparisons in national league tables between NHS trusts.
The inadequacy of the inpatient waiting lists as a measure of waiting times is particularly evident in conditions like cataracts and osteoarthritis, which need to reach a certain stage before an operation is performed. The precise point at which these patients are added to the waiting list varies widely among consultants. Hence a trust whose consultants tend to add their patients to the list at the first outpatient attendance will seem unfairly to have a longer waiting time than one whose consultants delay placing patients on the list until they are ready for the operation. The total postreferral wait, however, is the same in both trusts.
Continuous monitoring of waiting lists
Many hospital patient administration systems already incorporate a facility for the continuous monitoring of inpatient waiting lists, enabling patients approaching the guaranteed maximum wait to be called in urgently for treatment. These systems could readily be adapted to monitor the postreferral waiting lists as proposed in this paper. The essential requirement would be that they should have access to the date on which the general practitioner referral letter was received by the hospital. The value of these monitoring systems would be greatly enhanced by including a facility to identify patients who are waiting after their first outpatient attendance to be put on an inpatient or day case waiting list.
As pressure to get waiting time down even further intensifies, monitoring at both national and local levels becomes even more essential. We must ensure that shorter times spent on inpatient and day case waiting lists are not gained in any hospital at the expense of increased delays before being placed on the lists or increases in the numbers of deferred patients or those exempted from the guarantees. Deliberate manipulation of the system by providers to improve their position in the ratings would, however, be unthinkable. The vast majority of providers have been putting considerable effort into reducing waiting times at each stage of the process, many with great success. Certainly there was no evidence of manipulation in the three hospitals that I studied.
The prereferral wait is also an important factor. The time elapsing between a patient's initial presentation with symptoms to a general practitioner and attendance at an outpatient clinic may be crucial in conditions like cancer, in which early diagnosis may be vital.6 Extending the monitoring process to outpatient referrals would help to ensure that the referral pattern of general practitioner fundholders is not distorted by, for example, end of year financial considerations.
As far as most patients are concerned the total length of time that they have to wait for treatment after being referred by their general practitioner for an outpatient appointment - the postreferral wait - is likely to be more important than just the time they spend at the final stage of the process on the inpatient waiting list. Postreferral waiting times would therefore greatly help general practitioners and their patients in deciding where to seek treatment.
I think my former colleagues Charles Guthrie and Ingrid Gilray in the information services unit at Tayside Health Board headquarters for helpful discussions during the preparation of this paper. The opinions expressed in this paper are mine and not necessarily those of the employing authority.