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SPINE Volume 26, Number 23, pp 2615–2622
©2001, Lippincott Williams & Wilkins, Inc.
Safety, Efficacy, and Cost Effectiveness of Evidence-
Based Guidelines for the Management of Acute Low
Back Pain in Primary Care
Brian McGuirk, FAFOM, Wade King, MMedSci, Jayantilal Govind, FAFOM,
John Lowry, PhD, and Nikolai Bogduk, DSc
Study Design. A case-control study involving parallel
benchmarking audits was conducted.
Objective. To compare the safety, efficacy, and cost
effectiveness of evidence-based medical care and usual
care for acute low back pain.
Summary of Background Data. Although several sets
of guidelines have been promoted for the management of
acute low back pain, there is no evidence that following
guidelines results in better outcomes.
Methods. Special clinics were established, at which
trained medical practitioners managed patients with
acute low back pain according to evidence-based guide-
lines. Their outcomes were audited by independent re-
search nurses. Meanwhile, and separately, the outcomes
of patients managed by their own general practitioners
were audited by research nurses using the same instru-
ments of assessment.
Results. In both settings, patients showed remarkable
degrees and rates of recovery, with low rates of recur-
rence. However, evidence-based medical care resulted in
a significantly lower cost of treatment; a significantly
greater reduction in pain, sustained at both 6 and 12
months; significantly fewer patients requiring continuing
care at 3, 6, and 12 months; a significantly greater pro-
portion of patients fully recovered at 12 months; and
significantly greater proportions of patients rating their
treatment as extremely helpful and offering positive, un-
solicited comments about their treatment.
Conclusions. The immediate results from evidence-
based care are marginally better than those from good
usual care, but in the long term, evidence-based care
achieves clinically and statistically significant gains, with
fewer patients requiring continuing care and remaining in
pain. Consumers approve of evidence-based care. [Key
words: acute low back pain, evidence-based medicine,
treatment] Spine 2001;26:2615–2622
Several countries and agencies have promoted evidence-
based guidelines for the management of acute low back
pain.
1–3,11,26,28
Such guidelines have been promoted in
the belief that they should and will work. However, they
have been launched without any accompanying evidence
that they do, in fact, work.
The Australian National Musculoskeletal Medicine
Initiative was commissioned in 1996 to develop evi-
dence-based guidelines for a variety of acute, regional
musculoskeletal pain problems, and to determine the
safety, efficacy, and cost effectiveness of evidence-based
practice in comparison with usual care for these condi-
tions. In supporting this project, the Federal Government
provided funding not only for the development of guide-
lines, but also for their concurrent evaluation.
Paramount among the several regional pain problems
addressed by the Initiative was acute low back pain. The
current report describes the results from an audit of evi-
dence-based medical management for this condition.
This was the first study investigating evidence-based
guidelines in this field.
Materials and Methods
A set of evidence-based guidelines was developed for the man-
agement of acute low back pain by medical practitioners. The
guidelines were based on a comprehensive review of the litera-
ture, taking into account earlier published guidelines
1,28
and
the results of subsequently published systematic re-
views.
4,12,20–22,32,33,35
The guidelines covered the etiology and
taxonomy of acute low back pain, history and physical exam-
ination, medical imaging, and treatment. Although not yet en-
dorsed by any agency, they are under review for endorsement
by the National Health and Medical Research Council of Aus-
tralia.
5
The guidelines emphasize dealing with patients’ fears
and misconceptions, providing confident explanation, and em-
powering the patient to resume or restore normal activities of
daily living through simple exercises and graded activity, ac-
cording to the principles of Indahl et al,
15,16
supplemented as
necessary by simple measures such as analgesics and manual
therapy for symptomatic relief.
To test the efficacy of evidence-based care, 13 special urban
and rural clinics were established throughout Australia in both
hospital and community settings. These clinics were staffed by
medical practitioners (11 general practitioners and 4 specialists
in rheumatology, rehabilitation, or occupational medicine)
who had postgraduate training in musculoskeletal medicine,
who agreed to abide by evidence-based guidelines, and who
agreed to have their practice and outcomes audited by an inde-
pendent research nurse. The doctors in the clinics saw patients
referred to them by general practitioners in the locality of the
clinic, and in some cases, by the accident and emergency de-
partments of their hospitals. They provided evidence-based
treatment until either the patient recovered or 3 months had
elapsed. The guidelines and treatment explicitly focused only
on acute pain. No interventions were offered by the clinics after
3 months if and when chronic pain developed. However, in that
event, patients were referred to pain clinics or other services
after consultation with their referring general practitioners.
A parallel audit of usual care was conducted by enlisting the
cooperation of four general practice divisions. (In Australia, a
From the Newcastle Bone and Joint Institute, University of Newcastle,
Royal Newcastle Hospital, Newcastle, New South Wales, Australia.
Funded by a grant from the Commonwealth Department of Health and
Aged Care. The views contained in this report are not necessarily those
of the Department.
Device status category: 1.
Conflict of interest category: 14.
2615
general practice division is an autonomous organizational unit
of the general practitioners in a geographic region constituted
to represent these practitioners in academic and other endeav-
ors.) The participating general practitioners agreed to manage
their patients in their normal manner, and to have their prac-
tices and outcomes audited by an independent research nurse
appointed to and operating from the division’s headquarters.
To avoid contamination of the two samples, the general prac-
titioner divisions audited were in locations quite distant from
the locations of any evidence-based clinics in the study.
To be eligible for the study, patients had to be adults able to
give informed consent who had low back pain of less than 12
weeks duration that had not occurred within the preceding 12
months. Patients with trivial or fleeting problems were not en-
rolled. Individuals became eligible if their pain had been
present for several days, or if they had consulted their general
practitioner the second time for their current episode of back
pain. Participants were enrolled within 1 or 2 weeks after they
had been referred or nominated.
The study explicitly excluded patients with an active work-
ers’compensation claim. This was necessary to avoid jurisdic-
tional problems (e.g., who controlled certification), and to
avoid potential extraneous influences (e.g., from lawyers,
claims managers). Consequently, patients were excluded if they
had lodged a claim. However, injured workers who had sought
care from their own general practitioners but had not lodged a
claim remained eligible.
In the evidence-based clinics, the research nurse interviewed
patients when they attended the clinic, then followed them with
home visits as convenient to the patient. In the general practice
divisions, the nurse interviewed patients at home or at some
location convenient to the patient. In the first instance, all in-
terviews were face-to-face. Telephone interviews were used
only in exceptional circumstances, such as situations in which
the nurse or patient was unable to travel. They also were used
to confirm recovery or no change once the stable status of the
patient had been established in a face-to-face interview.
The evidence-based clinics operated part-time for 2 half
days a week. They recruited patients regularly over their period
of operation, which ranged variously from 18 months to 3
years over the course of the Initiative. For logistic and financial
reasons, the general practitioner divisions recruited patients
over a fixed 3-month period, which nevertheless provided a
cross-sectional sample of the patient types seen in general prac-
tice. In both settings, all the patients became eligible for a
3-month review. However, because the project had a fixed clos-
ing date, only the patients enrolled earlier than 6 months and
12 months before that date became eligible for 6-month and
12-month reviews, respectively. For that reason, the numbers
of patients seen at 6 months and 12 months were progressively
smaller than the number seen at 3 months.
The research nurses obtained baseline data at inception of
the study, and outcome data at 3 months, 6 months, and 12
months after enrollment from all patients who reached these
anniversaries. At each interview, to minimize the burden on the
patients, a minimum number of critical instruments was ad-
ministered. The main instruments used were a visual analog
scale for pain
6,7,10,13,14,17–19,23,27,29,30
and the MOS 36-Item
Short-Form Health Survey (SF-36).
24,25,36
In addition, patients
were asked about their use of prescribed treatment and any
other interventions. At inception of the study, they were asked
to nominate up to four activities of daily living they felt were
prevented or impeded by their pain, and that they most dearly
would want restored. At each follow-up visit, they were asked
which of these had been restored. At 3 months, patients were
asked to complete a treatment helpfulness questionnaire,
8
which included both a structured question and the opportunity
to record unsolicited responses.
Visual analog scores were recorded on a scale of 0 to 100
mm. The SF-36 scores for each patient were normalized as a
proportion of the normal score for their age. For these contin-
uous data, median values were determined for each group of
patients. Comparisons between groups and different times
were made using the Mann-Whitney test. For restoration of
activities of daily living, and for the use of continuing care, the
numbers and proportions of patients in each category were
tabulated and compared using the
2
test.
At each follow-up visit, the researchers tabulated the num-
ber of patients who had fully recovered, the number of those
whose pain had improved but who had not fully recovered, and
the number of those who were unchanged or worse. Recovery
was defined as a visual analog score of zero or less than 10 on
the 100-mm scale. Recurrence was deemed to have occurred if
a patient’s pain score returned to a level above 10. The recur-
rence rate was calculated as the percentage of patients with a
previous score below 10 whose pain had deteriorated to a level
above 10.
The costs of treatment were determined by summing the
costs of consultations, prescribed treatment, and any investiga-
tions. To these were added patient estimates of costs incurred
pursuing nonprescribed interventions.
The study was approved by the Ethics Committee of the
University of Newcastle, and also by the ethics committees of
various hospitals in which clinics were established.
Results
During the study period, the evidence-based clinics re-
ceived 547 patients with back pain. They were seen
within 0.6 ⫾0.88 weeks after referral. Of these 547
patients, 110 did not participate because of ineligibility,
a choice not to participate or continue, or inability to
participate for logistic reasons. Consequently, 437 pa-
tients commenced care.
At the first consultation or shortly thereafter, six pa-
tients (1.4%) were found to have red flag conditions: two
osteoporotic fractures, one crush fracture, and one car-
cinoma of the kidney, one carcinoma of the liver, and one
carcinoma of the prostate. These patients were referred
for appropriate management. The general practitioner
divisions saw 101 patients, 18 of whom declined to par-
ticipate. The remaining 83 patients enrolled in the audit.
Despite repeated attempts, 11 clinic patients and five
general practitioner patients could not be found for sub-
sequent follow-up evaluation.
At inception of the study, the patients seen in the ev-
idence-based clinics and the general practitioner divi-
sions were almost identical demographically and clini-
cally (Table 1). The patients in both groups had
moderate pain and impairment in physical and social
functioning, but they were essentially normal in other
respects. The women in usual care were slightly older
than those in the evidence-based clinics. The clinics saw a
slightly greater proportion of employed patients, but
2616 Spine •Volume 26 •Number 23 •2001
somewhat fewer who were pensioners (Table 1). The
95% confidence intervals of the proportions, however,
were not significantly different between the two groups.
The interventions provided by the evidence-based
clinics differed significantly from those provided in usual
care (Table 2). On the one hand, the evidence-based clin-
ics made greater use of home rehabilitation as a formal,
prescribed intervention; greater use of manual therapy
by the treating physician; and greater use of locally in-
jected anesthetic into tender muscles, albeit in a small
proportion of cases. On the other hand, they made less
use of physiotherapy, rest, hot packs, and opioids such as
dextropropoxyphene and nonsteroidal antiinflamma-
tory drugs. Medical imaging was used in only 7% of
cases, as compared with 30% in usual care.
In addition to treatments prescribed by their treating
physician, some patients in the usual care group used
other nonprescribed forms of care such as nonprescribed
nonsteroidal antiinflammatory drugs (23%), simple an-
algesics (20%), heat (30%), liniments (17%), massage
(16%), and complementary health care (23%). Signifi-
cantly fewer patients under evidence-based care (⬍8%)
used such care.
Evidence-based care involved longer and more fre-
quent consultations. Consequently, it was more costly in
these respects than usual care. These costs, however,
were offset by minimal expenditure on investigations,
particularly plain radiographs and computed tomogra-
phy scans, and by far less expenditure on physiotherapy
and other treatment services. In addition, clinic patients
spent less on nonprescribed treatments. Consequently,
the average cost per patient under evidence-based care
was $276 (Australian), was compared with $472 (Aus-
tralian) per patient under usual care. For evidence-based
care, the principal determinants of cost were consulta-
Table 1. Demographic and Clinical Features at Inception
Into the Study of Patients With Acute Low Back Pain
Undergoing Care at Evidence-Based (EB) Clinics or Usual
Care From Their General Practitioner
Feature
EB Clinics Usual Care
P*n Score n Score
Age
All 430 83
Median 47 53 0.001
Interquartile range 35–58 42–67
Women 231 43
Median 47 57 0.000
Interquartile range 36–58 44–71
Men 199 40
Median 47 51 0.209
Interquartile range 34–57 40–61
Occupation
Employed 295 45 0.010
Unemployed 17 1 0.212
Pensioner 73 23 0.02
Homemaker 44 14 0.082
Duration of illness (weeks) 430 83
Median 2.5 2.1 0.274
Interquartile range 1.0–7.9 1.3–4.1
VAS for pain (0–100) 430 83
Median 46 41 0.195
Interquartile range 26–65 21–59
Bodily pain 430 83
Median 0.40 0.39 0.756
Interquartile range 0.28–0.59 0.16–0.63
Physical functioning 427 82
Median 0.63 0.65 0.869
Interquartile range 0.37–0.88 0.37–0.93
Physical role 427 82
Median 0.00 0.00 0.977
Interquartile range 0.00–0.34 0.00–0.34
Social functioning 429 83
Median 0.72 0.70 0.660
Interquartile range 0.45–0.98 0.44–1.01
Emotional role 429 83
Median 0.80 0.80 0.485
Interquartile range 0.00–1.18 0.00–1.18
General health 427 83
Median 1.06 1.06 0.833
Interquartile range 0.88–1.21 0.81–1.21
Mental health 428 83
Median 0.97 1.00 0.757
Interquartile range 0.78–1.12 0.82–1.10
Vitality 428 83
Median 0.83 0.81 0.189
Interquartile range 0.55–1.09 0.56–1.01
* The Pvalue pertains to the difference between EB patients and usual care
patients.
VAS ⫽visual analog scale.
Table 2. The Nature of Interventions Prescribed for
Patients With Acute Low Back Pain in Evidence-Based
(EB) Clinics or Under Usual Care, and the Number (n)
and Proportion (⌸) of Patients Prescribed
Each Treatment
Intervention
EB Clinics
(n ⫽431)
Usual Care
(n ⫽83)
n⌸n⌸
Home rehabilitation* 357 0.83 17 0.20†
Manual therapy in office* 279 0.65 14 0.17†
Physiotherapy* 27 0.06 38 0.46†
Rest* 10 0.02 33 0.40†
Formal exercises* 121 0.28 29 0.35
Hot/cold packs* 26 0.06 21 0.25†
Injections*
Local anaesthetic into tender points* 75 0.17 1 0.01†
Caudal/epidural 12 0.03 0 0.00
Other 4 0.01 0 0.00
All other interventions 64 0.15 19 0.23
Referrals to specialist 6 0.01 3 0.03
Drugs
Simple analgesics* 90 0.21 23 0.28
Compound analgesics 10 0.02 4 0.05
Lesser opioids (e.g., dextropropoxyphene) 29 0.07 21 0.25
NSAIDs* 71 0.16 32 0.39
All other drugs 43 0.10 17 0.20
Pathology tests 6 0.01 3 0.04
Imaging (all types) 31 0.07 25 0.30†
Radiograph* 18 0.04 23 0.28†
Bone scan 3 0.01 0 0.00
Ultrasound 0 0.00 2 0.02
CT* 10 0.02 8 0.10†
MRI 1 0.00 1 0.01
* The most commonly used interventions in either the evidence-based clinics
or the general practice divisions.
† Significantly different proportions. The corresponding higher proportion is
highlighted in bold type.
NSAID ⫽nonsteroidal antiinflammatory drug; CT ⫽computed tomography;
MRI ⫽magnetic resonance imaging.
2617Safety, Efficacy, and Cost Effectiveness of Guidelines •McGuirk et al
tions (72%), drugs and treatment (7%), and nonpre-
scribed treatment (10%). Medical imaging accounted for
only 5% of costs. For usual care, the determinants were
consultations (12%), physiotherapy (24%), drugs and
treatment (23%), nonprescribed treatment (26%), and
imaging (14%).
At 3 months, the patients in both groups exhibited
major improvements that were both statistically and
clinically significant (Table 3, Figures 1 and 2). Improve-
ments achieved at 3 months were sustained at 6 and 12
months. Median pain scores dropped toward zero. Phys-
ical and social functioning reverted to normal levels.
Scores on other scales of the SF-36 that were normal or
near normal at inception of the study remained the same
or improved. Slightly more than 50% of the patients
experienced restoration of all or all but one of their de-
sired activities of daily living. More than 70% of the
patients in the evidence-based clinics and more than
50% of the patients under usual care required no con-
tinuing care (Table 4). Of the patients who did require
continuing care, approximately 50% continued to see a
medical practitioner and used analgesics, whereas 25%
pursued physiotherapy.
After treatment, no patient in the usual care group
failed to return to work. Only two patients under evi-
dence-based care (0.7%) had not returned to work. In
the usual care group, 29 patients (35%) lost time from
work for a median duration of 5 days (interquartile
range, 2–9 days). Under evidence-based care, 144 pa-
tients (33%) were off work for a median duration of 3
days (interquartile range, 2–9 days).
With respect to outcomes, no consistent, systematic,
or statistically significant differences were observed
among patients treated in evidence-based clinics in dif-
ferent locations or settings. Essentially, all clinics con-
tributed similar patients and similar results. Likewise, no
differences were observed among patients treated in dif-
ferent general practice divisions.
At 3 months, 67% of the evidence-based patients and
49% of the usual care patients had fully recovered. At 6
months, these figures were 70% and 64%, respectively,
and at 12 months they were 71% and 56%. The recur-
rence rates at 6 months and 12 months were low: respec-
tively, 16% and 16%, in the evidence-based clinics, and
7% and 27% in usual care.
The preceding conclusions were based on the results
from cross-sectional samples of patients who remained
in the study for 3, 6, or 12 months, until its date of
termination. However, not all patients presented for ev-
ery scheduled follow-up visit. Some missed the 3-month
review but returned at 6 months, and not all reached 12
months. However, in terms of clinical features, the pa-
Table 3. Median Scores for the Principal Outcome
Measures of Patients With Acute Low Back Pain Treated
in Evidence-Based (EB) Clinics or Under Usual Care, at
Inception of Study (0 months), Then 3, 6, and 12
Months Later
Outcome Variable
Outcome Median Score
0 Months 3 Months 6 Months 12 Months
Patients (n)
EB Clinics 430 376 239 203
Usual care 83 81 61 46
VAS
EB Clinics 46 2 3 2
Usual care 41 10 4 9
P* 0.195 0.001 0.210 0.042
Physical functioning
EB Clinics 0.63 1.02 1.04 1.07
Usual care 0.65 1.00 1.04 0.91
P* 0.869 0.364 0.197 0.006
Social functioning
EB Clinics 0.72 1.14 1.15 1.15
Usual care 0.70 1.13 1.13 1.15
P* 0.660 0.853 0.269 0.888
Physical role
EB Clinics 0.00 1.17 1.17 1.18
Usual care 0.00 1.12 1.12 1.12
P* 0.927 0.939 0.350 0.782
Bodily pain
EB Clinics 0.40 0.93 1.01 1.02
Usual care 0.39 0.79 0.90 0.90
P* 0.756 0.027 0.018 0.123
* The Pvalue pertains to the difference between groups at each period
according to a Mann-Whitney test. For both groups, all values at 3, 6, and 12
months are significantly different from those at study inception for that group
(P⫽0.000).
VAS ⫽visual analog scale.
Figure 1. Median scores on the visual analog scale (VAS) for pain
at inception of the study, then at 3 months, 6 months, and 12
months for patients with acute low back pain treated in evidence-
based (EB) clinics and those under usual care (UC). The scores of
the two groups are significantly different at 3 months and 12
months (Table 3).
2618 Spine •Volume 26 •Number 23 •2001
tients who reached only a 3-month assessment did not
differ statistically at inception of the study from those
who reached 6- and 12-month assessments. Neverthe-
less, to check whether the patterns expressed by this
cross-sectional data are valid, the data of patients avail-
able for assessment at every follow-up visit were ana-
lyzed. That analysis of longitudinal data bears out the
pattern of the cross-sectional data (Table 5, Figure 3).
In response to the structured component of the Treat-
ment Helpfulness Questionnaire, 82% of the patients in
the evidence-based clinics rated their treatment as ex-
tremely helpful, as compared with 43% of the patients in
usual care. The difference between these proportions is
significant (P⫽0.000). Approximately 73% of the pa-
tients in the evidence-based clinics offered unsolicited
comments about their treatment, 96% of which were
positive. Only 42% of the patients in usual care offered
comments, 74% of which were positive. The difference
between these proportions also is significant (P⫽0.000).
The significant differences in outcome between pa-
tients treated under evidence-based care and those man-
aged by usual care were significantly lower treatment
cost; significantly greater reduction in pain, sustained at
6 and 12 months; significantly fewer patients requiring
continuing care at 3, 6, and 12 months; and a signifi-
cantly greater proportion of patients fully recovered at
12 months, rating their treatment as extremely helpful,
and offering positive unsolicited comments about their
treatment.
In the current study, the patients who required con-
tinuing care are likely of greater interest and concern
than the patients who recovered because these patients
contribute to the ever-growing number of patients with
chronic back pain. On inquiry concerning the available
data, few consistent and systematic differences could be
detected between the patients who required continuing
care and those who did not. The cardinal, consistent
difference was that those who required continuing care
remained in pain. The patients who did not require fur-
ther care essentially had no pain. Otherwise, under both
evidence-based care and usual care, the patients who
required continuing care were significantly, but only
Figure 2. The median scores on the MOS 36-Item Short-Form Health Survey (SF-36) for bodily pain, physical functioning, and social
functioning at inception of the study, then at 3 months, 6 months, and 12 months for patients with acute low back pain treated in
evidence-based (EB) clinics and those under usual care (UC). The scores of the two groups for bodily pain are significantly different at
3 months and 6 months (Table 3). No other significant differences apply.
Table 4. The Proportions of Patients With Low Back Pain Treated in Evidence-Based (EB) Clinics or Under Usual Care
Who 3, 6, and 12 Months After Treatment Required No Continuing Care or Continued to Have Some Form of
Medical Care
Proportion of Patients
3 Months 6 Months 12 Months
EB
Clinics
(n ⫽374)
Usual
Care
(n ⫽72)
EB Clinics
(n ⫽250)
Usual
Care
(n ⫽60)
EB Clinics
(n ⫽216)
Usual
Care
(n ⫽46)
No continuing care 0.72 0.73 0.77
0.56 0.53 0.63
Continuing care 0.28 0.27 0.23
0.44 0.47 0.37
P* 0.005 0.029 0.033
The Pvalue pertains to the significance of the difference between proportions of patients under evidence-based care or usual care who required no continuing
care.
2619Safety, Efficacy, and Cost Effectiveness of Guidelines •McGuirk et al
slightly, more impaired in terms of physical functioning,
social functioning, and role physical. However, the in-
struments of assessment used in the current study did not
identify any predictors of the need for continuing care.
Discussion
A report restricted to a prescribed page limit does not
allow a detailed description of the details and subtleties
inherent in the methods and results from a study of such
complexity as that reported. For these reasons, it was
impossible to report exactly what treatments were ad-
ministered to each patient, or what transpired in the in-
teractions among patients, doctors, and nurses. Nor can
we elaborate the outcomes in detail, or estimate which
components of the provided treatment contributed most
to the efficacy. Only the principal outcomes of the cur-
rent study have been reported.
The reasons for not using a randomized design are
worthy of discussion. Foremost, the investigators wished
not to incur a nocebo effect. When planning the study,
the investigators foresaw that patients attending a “spe-
cial”clinic who summarily were randomized to resume
care from their general practitioner could be disaffected.
Not only might they be less inclined to recover under
these conditions, they also could feel disenfranchised,
reporting that they were not afforded the “new”“spe-
cial”treatment provided by the government. For this
reason, the investigators elected to conduct parallel au-
dits, and to rely on large numbers to dilute potential
confounding differences. Furthermore, because of the
aforementioned effects, a randomized trial would not
provide “natural”data on the practices and outcomes of
usual care. Because this was a critical objective of the
study, the investigators elected to survey usual care with
the least interference. In essence, the design adopted was
that of two parallel benchmarking exercises.
To this end, the audits were conducted in geographi-
cally separated locations. This ensured that the samples
would not be cross-contaminated, either by patients
meeting and comparing the treatment they had received
or by referring general practitioners having patients from
their practice under both evidence-based care and their
own care, which by inference could be different.
Although the adopted design avoided a nocebo effect,
it did not avoid a possible placebo influence, but neither
could a randomized trial. It is difficult to mask evidence-
based care if patients are to be fully informed. When
patients see a special and unfamiliar medical practitio-
ner, the blinding is corrupted. A rigorous, randomized
trial of evidence-based care would require that patients
be treated by their own familiar general practitioners,
with half of whom electing covertly to abide by evidence-
based guidelines. Given the results of the current study,
however, that rigor may be superfluous.
The results of the current study reflect favorably on
evidence-based care. Statistically significant differences
were uncovered regarding reduction of pain, reduced
need for continuing care, lower cost, and greater con-
sumer satisfaction. Upon long-term follow-up, no pa-
tients under evidence-based care were found to have had
a red flag condition. Consequently, no serious disorders
were missed because radiographs were not taken during
the acute management. Relying on a red flag checklist
based essentially on history
5
proved to be very safe.
In terms of immediate outcome (at 3 months), few
differences were observed between evidence-based care
and usual care. At best, evidence-based care achieved a
slightly greater reduction in pain. However, this result
shows that at the very least, the same or slightly better
outcomes can be achieved without the usual rate of rest,
nonsteroidal antiinflammatory drugs, and medical imag-
Figure 3. The median pain scores on the visual analog scale (VAS)
at inception of the study, then at 3 months, 6 months, and 12
months for patients with acute low back pain treated in evidence-
based (EB) clinics (n ⫽160) and those under usual care (UC) (n ⫽
45) who were assessed at every time period. The scores for the two
groups are significantly different at 3, 6, and 12 months (Table 5).
Table 5. Visual Analog Pain Scores of Patients With Low Back Pain Seen in Evidence-Based (EB) Clinics and Usual
Care Who Presented For Assessment at Inception of Study, Then at 3, 6, and 12 Months
Inception 3 Months 6 Months 12 Months
Median Range Median Range Median Range Median Range
EB clinics (n ⫽160) 45 30–61 3 0–15 3 0–13 2 0–12
Usual care (n ⫽45) 42 23–67 16 4–49 15 0–53 10 0–44
P* 0.7361 0.0003 0.0013 0.0478
* The Pvalue pertains to differences between clinic patients and usual care patients at each period. For each group of patients, all scores at 3, 6, and 12 months
are significantly better than those at inception of the study (P⫽0.000).
2620 Spine •Volume 26 •Number 23 •2001
ing. On the other hand, evidence-based care achieved
significant long-term gains, resulting in fewer patients
with chronic pain requiring continuing care. Notwith-
standing the clinical and social significance of this dif-
ference, it also would amplify the cost differences iden-
tified. The costs calculated in the current study
pertained only to the first 3 months of management,
and did not include the costs of continuing care.
Perhaps most significantly, consumers approved of
evidence-based care. Their comments indicated that nei-
ther pain nor relief concerned them as much as reassur-
ance and empowerment. Moreover, some were satisfied
with these despite persistence of their pain. This issue
will be the subject of a future report.
It might be argued that the evidence-based care in the
current study was provided by an elite cadre of medical
practitioners, and that its effectiveness is therefore over-
stated. The practitioners were indeed specially trained
and skilled in musculoskeletal medicine, and they volun-
tarily agreed to abide by guidelines. This was in contrast
to having guidelines imposed ex cathedra on unmoti-
vated practitioners. However, in this regard, the study
consciously sought to determine the efficacy of evidence-
based care under optimal conditions. There is every pos-
sibility that evidence-based guidelines alone are not ef-
fective, and that they require not only training, but also
commitment from those who use them. The findings
from the current study indicate that if these conditions
are met, evidence-based care is effective for back pain.
The size of the effect in current study may not be
startling clinically. Regarding relief of pain, evidence-
based care was only marginally better than usual care.
However, it might be considered that the general practi-
tioners who volunteered to have their usual care audited
were among the more responsible, interested, and dedi-
cated general practitioners. Moreover, realizing that they
were under scrutiny, they might have tried harder in the
management of their patients. The results obtained in
usual care may therefore reflect what occurs under
good usual care, and thus may not be generalizable to
average usual care. What the current study does not show is
whether good evidence-based care is substantially better
than average usual care, or how average evidence-based
care might compare with either good or average usual care.
A measure of average usual care is elusive.
A striking feature of the current results is how well
patients fared under usual care. Notwithstanding the dif-
ferences between usual and evidence-based care, a large
proportion of patients recovered and remained well
throughout the 12-month follow-up period. Recurrence
rates were low, which contrasts with the findings from
recent studies in other countries. A British study found
that as few as 20% of patients were symptom free at 12
months.
9
Figures from the United States echo that pro-
portion.
34
A longitudinal Dutch study reported that
70% of patients experience a recurrence after a median
period of 7 weeks.
31
The results of the current study are
the converse of these figures.
On the one hand, this may say something about the
Australian people. They may be hardier than Europeans
or Americans, or they may respond better to good med-
ical care. On the other hand, the social circumstances of
the patients in the current study may have been different.
The study deliberately avoided workers’compensation
and insurance issues. In the first instance, compensation
patients were avoided to avert potential conflicts be-
tween clinic doctors and the referring general practitio-
ners in terms of certification for time off work or return
to work. In the second instance, this government-funded
study addressed care subsidized by the government un-
der Medicare, not care funded by insurers. The findings
of the current study therefore show the results of evi-
dence-based care and good usual care for acute low back
pain uncomplicated by compensation issues. The data
indicate that under these conditions, the prognosis for
acute low back pain is very favorable regardless what
system of care is used.
If the course of acute back pain is different under a
compensation system, then there must be influences
other than those of natural history and good medical
care. Perhaps workers’compensation patients have more
serious injuries as the basis for their pain than the pa-
tients in the current study. In this regard, no pathoana-
tomic diagnosis was sought or offered for the patients in
the current study, in accordance with evidence-based
guidelines, because such a diagnosis is neither possible
nor necessary. As borne out by the results, most patients
recover and do not warrant intensive and expensive pre-
cision diagnosis.
Alternatively, the current results may imply that
workers’compensation patients are subject to negative
influences. Their recovery, as compared with that of the
current patients, may be impaired by the way the system
operates, how they are treated, and what they expect.
This could be determined only by dissecting the workers’
compensation system. The results of the current study
indicate that outcomes can be better than they appear to
be from the literature available at this writing.
Notwithstanding the favorable outcomes of both ev-
idence-based care and usual care in the present study,
these outcomes are not perfect. Some patients still do not
recover even under good evidence-based care. In this re-
gard, the current study demonstrated what might be the
clinically and socially most significant benefit of evi-
dence-based care. A significantly greater proportion of
patients under evidence-based care recover fully, and sig-
nificantly fewer require continuing care. Although the
latter proportion may be small, these patients languish
and add to what becomes an ever-increasing population
of patients with long-term back pain. When conscien-
tiously applied evidence-based care fails to eliminate the
problems of these patients, persisting with the same man-
agement would seem inappropriate and inefficient. Con-
sequently, there is a need to redirect these patients to
more concerted care of a nature perhaps not practicable
2621Safety, Efficacy, and Cost Effectiveness of Guidelines •McGuirk et al
in primary care, and perhaps sooner in the course of
acute pain than has been the custom.
Key Points
As compared with usual care, evidence-based care for
acute low back pain
●achieves marginally better symptomatic relief
●results in less need for continuing care
●achieves greater rates of full recovery
●is less expensive.
●attracts greater consumer satisfaction.
Acknowledgments
The authors thank the members of the Hunter Urban
Division of General Practice, the Northwest Slopes
(NSW) Division of General Practice, the Osborne Park
Division of General Practice, and the Fremantle Division
of General Practice for their sincere participation in this
study, and the medical and nursing personnel who
staffed the clinics.
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Address reprint requests to
Nikolai Bogduk, DSc
Newcastle Bone and Joint Institute
Royal Newcastle Hospital
Newcastle, NSW 2300
Australia
E-mail: mgillam@mail.newcastle.edu.au
2622 Spine •Volume 26 •Number 23 •2001
