Abstract
Background Most patients seeking help for back pain are managed in primary care.
Aim To describe the content and outcome of ‘usual care’ for low back pain in primary care trials.
Design of study A systematic review of randomised controlled trials published since 1998.
Method Randomised controlled trials of back pain in adults were scrutinised to obtain data on treatment and outcome measures in groups receiving usual primary care. A narrative review of the resulting heterogeneous data was undertaken.
Results Thirty-three papers were identified for analysis. Overall the exact nature of the treatment received in the ‘usual’ primary care group was poorly recorded. Medication was frequently used, and there were suggestions that levels of opioid prescription were higher than might be expected from clinical guidelines. Requesting of plain-film X-rays occurred more often than recommended. There was very little information to suggest that doctors were promoting physical activity for patients with back pain. Disability scores (Roland–Morris Disability Questionnaire) and pain scores improved over time for patients with acute or subacute back pain, but not for those with chronic pain.
Conclusion Treatment received by patients with back pain was varied and often not in line with back-pain guidelines, particularly with respect to opioid prescription and X-ray investigation. The content of the ‘usual care’ arm in trials is crucial to interpreting the outcome of studies, but was poorly described in the papers reviewed. Future trials should more fully describe the ‘usual care’ arm.
INTRODUCTION
Low back pain is a common condition that is frequently seen in primary care. In the UK there are between 3 and 7 million GP consultations for back pain in a year. Fifty-two million working days are lost each year and, at any one time, 6% of the working population will have had at least one day off work in the last 4 weeks due to back pain.1 The annual cumulative consultation rate of patients presenting to their GP with back pain is 6.4%.2
Despite evidence-based guidelines for the management of low back pain,3,4 chronic or recurrent back pain is common and it continues to pose considerable challenges and frustrations for patients and practitioners. Attempts have been made to address this situation using educational programmes for GPs to promote the adoption of guidelines, but these have failed to show significant changes in everyday clinical practice.3,4 One reason for this may be that the nature of routine clinical practice in primary care has not been adequately considered when producing guidelines.
‘Usual care’ is often used as the control or comparator group in randomised controlled trials. It is important to know the content of these control treatments in order to interpret the effect sizes published in trials. The current study is a systematic review with the following specific objectives:
to describe the treatments contained within ‘usual care’ approaches to low back pain, as reported in primary care-based randomised controlled trials published between 1994 and 1997 (a period when many clinical guidelines were published); and
to describe the clinical course of patients randomised to the ‘usual care’ approaches outlined in the first objective.
RESULTS
Study selection
The initial search yielded 164 potentially relevant studies. After examining the full text of 54 papers, 33 were included in the review.3,12–43 This process is detailed in Figure 1.
Figure 1 Systematic review flowchart.
Study characteristics
Study characteristics are presented in detail in Appendix 2. Type of care given or intended to be given in the usual care control group is described, in addition to the outcome of the experimental intervention compared with usual care.
Of the 33 studies identified, eight investigated patients with acute back pain,13–15,32,34–36,39 11 with patients who had subacute pain,16,18–21,23,27,33,38,41,42 six examined patients with chronic pain,17,24–26,31,37 and eight studies investigated patients with mixed-duration pain.3,12,22,28–30,40,43
Baseline RMDQ score, where appropriate, is given to describe the severity of back pain in participants entering the trials. The studies were conducted in Australia, Canada, Finland, Mallorca, the Netherlands, Norway, Sweden, UK, and US. Thirty out of 33 studies assessed were deemed to be of good quality (that is, they achieved a quality score of ≥3 out of 5).
Methodological quality
In the 33 studies, one study scored 1,34 two scored 2,27,30 13 scored 3,12,17,19–22,26,29,32,37,40–42 16 scored 4,3,14–16,18,23–25,28,31,33,35,36,38,39,43 and one scored 5 out of a maximum score of 5.13 In 16 out of 33 studies it was not possible to tell if the outcome assessor was blinded,3,12,17–22,26,27,29,30,34,37,41,42 and in only three of 33 studies were the patients blinded to the nature of the treatment group.3,13,18 In two studies it was not stated if the treatment allocation was concealed,30,40 and in three it was not possible to tell if the analysis was by intention to treat.27,32,34 All papers reported the drop-out rates.
Content of usual care approaches
Adequacy of description of usual care
Of 33 studies, 11 had no description of either the allowed or actual treatment in the control group,14,17,18,22,24,27,28,30,32,40,42 seven had a description of both,15,23,26,29,35,38,41 six described just the actual treatment,3,22,25,33,34,43 and nine just the allowed treatment.12,13,16,19,20,31,36,37,39
The 10 most commonly recorded aspects of usual care are presented in Table 1. Of these 10 common aspects, a mean of 3.1 items (SD 2.2) were reported in the studies included in the review. Appendix 3 gives more information about aspects of consultations and demonstrates the wide variation in the detail of recording of usual care.
Table 1 Ten most commonly recorded aspects of usual care.
Consultation rates with GP
Due to the heterogeneous ways in which data about consultations were collected, it was not possible to perform a comprehensive quantitative analysis. Overall, 17 of 33 papers reported data on consultation rates. The following qualitative data were found:
Acute back pain. Four of eight studies described consultation rates per patient, one found a rate of 3.9 (no SD stated) consultations in 1 year,36 and another 3.3 (SD 1.6) in 8 weeks.15 Another found that 60% of patients presented to their GP once, 31% twice, and 9% more than twice in the course of a year.13 A fourth states that consultation rates were similar for patients in the experimental and control arms, although figures are not given.39
Subacute back pain. Four of 11 studies provide data on consultations for subacute back pain. One found 62.5% of patients presented to their GP in the first 3 months of the trial, and 51.1% in the second 3 months.33 A second study reported that 21% consulted once, 3% twice, and 5% three or more times in the first 6 months, and 16%, 3%, and 5% respectively at 9 months.21 Mean number of visits to the GP in 1 year was six in a further study.20 Jellema et al found that 24% of patients were seeking additional help from their GP in the first 6 weeks, and 28% in the remainder of the year of the study.18
Chronic back pain. Two of six studies reported data on consultations for chronic back pain. One reported a mean of 13.2 (SD: 5) visits in one year,31 and another reported a mean of 1.2 at baseline for the previous year and 1.7 in the year of the study.25
Mixed-duration back pain. Of eight papers, one found the mean number of visits to be 3.6,29 and one found 4.8 visits for mixed-duration back pain.22 Thomas et al reported that 40% of patients presented to the GP in the first 12 weeks of their study.43
Medication
Only 12 out of 33 studies gave information about medication taken by patients for their back pain.3,15,21,24–26,31,33,38,39,41,43
Many patients were taking medication at baseline, with figures reported of 69%,39 80%,24 90%,43 and 69% (prescribed) and 73% (over the counter).21
Two papers gave information about opioid prescription: 34% of patients in a US study,15 and 18.7% in the UK3 were prescribed them. Unfortunately, there was no information about the strength of the opiates or whether combination drugs were prescribed.
Work absence
Information about absence from work was quite heterogeneous due to the way in which authors recorded this information and differences in the type of usual care; some studies only recruited patients who were absent from work because of back pain.33,35 It is important to remember this when comparing data about sick notes from different countries. The different procedures for obtaining a sick notes in different countries may give a false interpretation of the data. As mentioned in the paper Dutch GPs do not give sick notes, British GPs do.
Acute back pain
One study reported that 81% of patients had no certified sick leave, fewer than 9% had 10 or more days of certified sick leave in a year, and overall there was a mean of 3 days' sick leave.13 Another reported a mean 2.2 days (SD: 3.4) of sick leave since randomisation at 8 weeks' follow-up.15
Subacute back pain
Patients reported a mean of 14 days of sick leave at baseline,21 and 15 in the 3 months before commencement of the study.19
Chronic back pain
Varied information was found related to work absence for chronic back pain. Two studies reported that 50%,31 and 57.3%17 of patients were off sick at baseline, whereas in another study the patients only had 3 days off sick at baseline.25
Activity levels and exercise advice
Three studies gave details on the activity levels of patients before they presented to their GP19,32,33 and three reported the advice given to patients about exercise during the trial.15,31,33
Physiotherapy
For acute back pain, 7%15 and 8.6%39 of patients were referred to physiotherapy. For subacute back pain, 18%,18 31%,21 and 92.9%33 of patients receiving usual care were referred to physiotherapy at baseline or in the first 6 weeks. For mixed-duration back pain 49% were referred within the first 12 weeks.43 In the case of chronic back pain it was not possible to compare data in a meaningful way, due to heterogeneity as discussed in relation to work absence.
Radiology
Use of plain film X-rays in the management of back pain varied, particularly between countries. The percentages of patients having this investigation were 19% (US),15 53.6% (Canada),33 7% (UK),21 and 4% (UK).29
Clinical course of patients randomised to usual care
Functional disability (RMDQ score)
The data shown in Figures 2a and 2b suggest that the speed at which RMDQ scores improve is inversely related to the duration of back pain: that is, the longer the duration of pain, the slower the rate of improvement. In acute and subacute pain there was a definite trend for improvement. The single study that did not follow this trend16 involved usual care provided by university-affiliated clinics and the emergency department of a hospital in an inner-city setting in the US; as such, these patients may not be representative of patients normally managed in primary care.
Figure 2a Change in Roland–Morris Disability Questionnaire (RMDQ) scores over time according to duration of acute/subacute back pain.
Figure 2b Change in Roland–Morris Disability Questionnaire (RMDQ) scores over time according to duration of chronic back pain.
Pain score
For acute and subacute pain there was a general trend for pain scores to improve with time, as observed on the 0–10-point pain scale used to rate the studies. In two studies acute pain mean pain scores improved by 5.8 and 2.0 between baseline and their endpoints respectively.13,35 For subacute pain, mean pain scores improved by 1.2, 5.0, 2.0, 1.0, and 3.9 respectively.16,18,19,21,33
For patients with chronic pain, the pain score changed little over the course of the study, with changes in mean pain scores of 0.9, −0.8, 0.6 and −1.8 respectively (a negative value meaning reduction of pain).24–26,31
Satisfaction
For acute pain, mean satisfaction scores at study endpoint were 7.2 (treatment),35 7.0 (explanation),35 and 4.1 (overall), according to the 0–10-point satisfaction scale used to rate the studies.15 In subacute pain, endpoint satisfaction scores were 4.7,33 and 4.1.19 In one study on chronic back pain the mean endpoint satisfaction score was 4.4.24 A study on mixed-duration back pain expressed this differently, with the number of patients who were very satisfied or satisfied at 85% following their initial consultation, and at 70% after 6 weeks (Figure 2c).22
Figure 2c Change in Roland–Morris Disability Questionnaire (RMDQ) scores over time according to duration of mixed back pain.
DISCUSSION
Methodological quality
That many studies did not have blinding of patients or outcome assessors is not unusual. Often blinding is not possible, or even sensible, due to the pragmatic nature of the trial design, the interventions used, or ethical constraints.
Studies were presented in different ways, which made quality assessment and data extraction difficult to carry out. Future randomised controlled trials on back pain should be presented in line with Consolidated Standards of Reporting Trials (CONSORT) recommendations.44
Overall, most papers reviewed were of an acceptable quality according to the study's quality scale. A small number of trials failed to describe concealment of allocation to treatment,30,40 or intention-to-treat analysis.27,32,34
Direct comparison between studies was difficult due to the differing ways in which data were recorded. For example, pain experienced by patients was assessed using Visual Analogue Scale, modified Von Korff Pain Scale, Aberdeen Back Pain Scale, and the Extended Aberdeen Spine Pain Scale. Nevertheless, the patterns of changes in pain were similar to those for disability, with patients with acute and subacute back pain showing larger improvements than participants with chronic back pain.
Description of usual care
Overall, usual care was poorly described in these studies. Historically, there has been a tendency to allow care in the control group to be according to the normal practice of the care provider, with little or no recording of what actually took place. This contrasts with the intervention treatment, against which usual care is compared, which is often described in great detail.
It is clear that healthcare providers vary widely in their preferred practices, due to many factors including their experience and the expectations of the population in which the studies are set. As such, control groups in separate studies reviewed here may receive a range of different treatments. This makes comparison between studies difficult.
Although the practice of comparing a new treatment with the prevailing current practice is well accepted, interpretation of such studies is problematic when the usual care groups vary so widely and are not adequately described. This is particularly pertinent given that a healthcare provider may act differently purely by knowing their practice is under scrutiny.
Attempts to standardise usual care have shown little effect in changing clinician behaviour.3 It is important to accept that usual care is heterogeneous, and this needs to be taken into account when interpreting the results of studies. The present authors suggest that a minimum dataset about usual care is recorded to improve understanding of the treatments received in the usual care group (Table 1 and Appendix 2). This includes information about radiology usage, other investigations ordered, medications used (prescribed or over-the-counter), sick notes issued, use of written materials, recording of activity levels, details of exercise advice given, consultation rates, physiotherapy undertaken, and hospital referrals.3
Content of usual care
It is difficult to draw any firm conclusions about how frequently primary care consultation is allowed or what actually happens in the usual care approaches. Marked differences existed in the control groups due to the country involved, variation in the study designs, and methods of recording consultation activity; only half of studies reported data and the results showed no pattern.
Similarly, the overall recording of medication use was quite poor. This is disappointing in that medication use has significant financial costs for the patient and the health economy, and is associated with a not-insignificant number of side-effects.
This review found that many patients take over-the-counter medication for their back pain, and GPs often provided additional medication. Data were limited, but there was a suggestion that levels of opioid prescription were quite high,3,15 given the message in back-pain management guidelines that suggest using weak opioids as ‘add-on’ treatments when paracetamol or non-steroidal anti-inflammatory drugs provide insufficient pain relief.8,45 Compound analgesics are not recommended as they do not allow separate titration of the constituent medications, and there are concerns about dependence with strong opioids.8,45
Unfortunately, in the studies in this review, information was not recorded about the strength of opiates or whether combination products were used. It may be that the concerns about strong and combination opioids are overemphasised, particularly when the majority of patients will recover from their back pain in a few weeks. A GP faced with a patient who is in pain, despite taking simple painkillers, may well decide that it is appropriate to prescribe these drugs in the short term, but with close monitoring for side-effects and over-usage. It is important to record more detailed information about the types of drugs used to treat back pain, and their effectiveness and safety.
It is generally accepted that plain-film X-rays are not helpful in the management of most patients with back pain and represent an avoidable source of radiation.6,46–48 This review found that the use of X-rays varied widely between countries, from 4% of cases in the UK,29 to 53.6% in Canada.33 Reasons for requesting investigations are complex and involve many factors including patient and doctor beliefs and knowledge, country-specific healthcare systems, and patient satisfaction.
The tension between guideline advice and actual clinical behaviour is illustrated by a survey of GPs that found that they would almost always or sometimes refer for X-ray in 70% of patients with non-recurrent backache of less than a month's duration: 88% per cent of requests were to reassure the patient, and 78% to reassure the doctor.49 This finding is not confined to low back pain consultations, and it has been shown that perceived patient pressure, rather than clinical need, is the reason behind a significant minority of investigations.50 Clearly, it is desirable to reduce patient exposure to radiation, but to achieve this goal a guideline must be of practical use to doctors in primary care. The guideline must include adequate explanation of the rationale behind each recommendation, address the needs for reassurance on the part of the patient and doctor, and be adaptable to local resources (for example, it is no use advocating magnetic resonance imaging instead of plain-film X-rays if it is not readily available).
The clear messages from trials and guidelines are that patients with low back pain should continue with normal activities, even if uncomfortable, and stay at or return to work.8 The papers included in this review did not, in general, report on this important aspect of patient care. One possible reason for this might be that is not the normal practice of GPs to record this information. Also GPs may not feel able to give specific advice about exercise, due either to lack of training or fear of litigation should the patient develop a problem related to exercising. GPs are well placed to give exercise advice to patients, and there is a need to address these issues to encourage and support people who would benefit from increasing their activity.51
Course of symptoms
The relatively small number of studies involved makes it difficult to undertake a meaningful data synthesis and arrive at firm conclusions. However, Figures 2a and 2b suggest that the speed at which the RMDQ score changed over time depended on the duration of the back disorder. For acute pain there was a trend for RMDQ scores to fall rapidly over the first few weeks (Figure 2a), and this improvement was maintained throughout the study period. For chronic pain sufferers the outlook was much less promising, and RMDQ scores did not tend to improve with time.
Usual care groups in the studies in this review were given a range of treatments but, despite this, it appears that the effectiveness of usual care (if measured as improvement of RMDQ score) may be related more to the duration of the episode than to the type of care given.
Usual care is variable in content and effectiveness. That it is also poorly described compounds this problem and makes comparison between studies even more difficult. As such, it is important that usual care is not regarded as a uniform control against which interventions are compared without attempting to understand what it consists of. This heterogeneity may undermine the fundamental basis for calculating sample sizes in future trials. Agreement is needed as to what information should be recorded in future trials, and conformity to CONSORT needs to be improved.