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National Collaborating Centre for Primary Care (UK). Low Back Pain: Early Management of Persistent Non-specific Low Back Pain [Internet]. London: Royal College of General Practitioners (UK); 2009 May. (NICE Clinical Guidelines, No. 88.)

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Low Back Pain: Early Management of Persistent Non-specific Low Back Pain [Internet].

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9Invasive Procedures

9.1. Recommendations for invasive procedures

9.1.1.

Consider offering a course of acupuncture needling comprising up to a maximum of 10 sessions over a period of up to 12 weeks.

9.1.2.

Do not offer injections of therapeutic substances into the back for non-specific low back pain.

9.2. Acupuncture and related treatments

Clinical question: What is the effectiveness of acupuncture (including PENS & neuroreflexotherapy) compared with usual care or sham on pain, functional disability or psychological distress?

9.2.1. Clinical evidence

A total of seven studies were identified and included: 4 RCTs and 1 systematic review on acupuncture, 1 systematic review on neuroreflexotherapy and 1 RCT on Percutaneous Electrical Nerve Stimulation (PENS) for low-back pain.

9.2.1.1. Acupuncture

One systematic review assessed the effects of acupuncture for the treatment of non-specific LBP and dry-needling for myofascial pain syndrome in the low-back region (Furlan, A. D., Van-Tulder, M. W., Cherkin, D. C. et al, 2005). The Cochrane library, MEDLINE and EMBASE databases were searched, as well as the Chinese Cochrane Centre database of clinical trials and a Japanese controlled trial database. RCTs including adults with non-specific LBP and myofascial pain syndrome in the low-back region were included. RCTs including subjects with LBP caused by specific pathological entities such as infection, metastatic diseases, neoplasms, osteoarthritis, rheumatoid arthritis or fractures were excluded. LBP associated with sciatica as the major symptom was also excluded. Articles evaluating acupuncture or dry-needling treatments that involve needling were included. Studies were included regardless of source of stimulation (eg hand or electrical stimulation).

With regards to acupuncture versus sham therapy 4 trials met this guideline’s selection criteria. Treatment interventions varied between trials; patients received 6 × 30min over 6 weeks in one, 20 × 30min over 12 weeks in another, 8 × 30min over 4 weeks in the third trial and 12 × 30min (3 times a week) in the fourth one. The pooled analysis (N= 314) suggested evidence for pain relief at shorter-term follow-up (up to 3 months), but these effects were not maintained at the longer-term follow-ups, nor were they observed for functional outcomes. Compared to no treatment, one low-quality RCT suggested some evidence for pain relief and functional improvement for acupuncture at short-term follow-up. The included studies were very heterogeneous in terms of population, type of acupuncture administered, control groups, outcomes measures and timings of follow-up. Although the conclusions show some positive results of acupuncture, the magnitude of the effects was generally small.

This was a high quality systematic review with a very low risk of bias.

One randomised controlled trial involved participants recruited through local newspapers and some who contacted the trial centres spontaneously (Brinkhaus, B., Witt, C. M., Jena, S. et al, 2006).

Those included had to be aged 40–75, have a clinical diagnosis of chronic back pain lasting more than 6 months, have a pain intensity of 40 or more for the previous 7 days (on a 100mm VAS). They had to have only used non-steroidal anti-inflammatory drugs for the past 4 weeks. A total of 2250 patients applied to be included in the study, of those only 301met the criteria of the study, these were then randomized into three groups, at a 2:1:1 ratio to acupuncture (140 patients), minimal acupuncture (70 patients) and no treatment (74 patients) (the control group).

The participants in the acupuncture group received 12 × 30 minute sessions over 8 weeks of acupuncture which used needles of an unspecified length and which were only stimulated once during each session. Sessions occurred usually twice a week for 4 weeks and then once a week for the last 4 weeks. The treatment needled a selection of local and distant points, including (bilaterally) at least four local points from the following: Bladder 20–34; Bladder 50 to 54; Gallbladder 30; Governing vessel 3, 4, 5 and 6; extraordinary points Huatojiaji and Shiqizhuixia. If patients had local or pseudoradicular sensations at least 2 local points were acupunctured. Other acupuncture points including ear and trigger points could also be chosen individually. The participants randomized to the minimal acupuncture group also received 12 × 30 minute sessions over 8 weeks where at least 6 out of 10 predefined non-acupuncture points were needled bilaterally using a superficial insertion with fine needles (length 20–40 mm), these points were not in the lower back where participants experienced pain. The final group which received no acupuncture was told they were on a waiting list for 8 weeks, after which they received normal acupuncture, (therefore were only included in the 8 week follow up).

The results of the study showed a statistically significant difference in pain scores between the acupuncture and no acupuncture groups (P <0.001 at 8 weeks). However, no significant difference in pain between the acupuncture and minimal acupuncture groups was found at 8, 26 and 52 weeks (the acupuncture group did have slightly better outcomes than the minimal acupuncture group).

This was a well conducted RCT with a low risk of bias.

One randomised controlled trial involved participants recruited through newspapers, magazines, radio and television (Haake, Michael, Müller, Hans Helge, Schade, Brittinger Carmen et al, 2007). Those included had to be over the age of 18 (average age of 50), have a clinical diagnosis of chronic back pain for 6 months or longer, have a Von Korff Chronic Pain Grade Scale (CPGS) grade 1 and Hanover Functional Ability Questionnaire (HFAQ) less than 70%. They had to have been therapy-free for 7 days or longer, be able to speak read and write German, and have signed a written consent form. A total of 1802 participants applied to be included in the study, of those only 1161met the criteria of the study, these were then randomized into three groups of 387 patients each to receive one of acupuncture, sham acupuncture or conventional treatment (the control group).

The participants in the acupuncture group received 10 × 30 minute sessions of verum acupuncture which used sterile disposable needles of 0.25×40mm or 0.35×50mm, with no electrical stimulation. They attended usually 2 sessions a week for 42 days. The treatment needled 14–20 fixed and additional points (from a prescribed list) chosen on the basis of traditional Chinese medicine diagnosis, including tongue diagnosis. De qi sensation was elicited by manual stimulation. The participants randomized to the sham acupuncture group also received 10 × 30 minute sessions where 14–20 needles were inserted without stimulation 1–3mm on either side of the lateral part of the back and on the lower limbs avoiding all classical acupuncture points or meridians. The final group which received conventional treatment was also seen in 10 × 30 minute sessions which followed German guidelines of a multimodel treatment program which included physiotherapy and exercise (and other treatments) by physicians and physiotherapists. The results of the study showed a statistically significant difference in pain between the two acupuncture groups together (verum and sham) and the conventional treatment where ½ the patients receiving acupuncture benefited compared to only a ¼ who received conventional treatment. However, there was no significant difference in pain scores between verum acupuncture and sham acupuncture (3.4% difference, P =0.39).

This was a well conducted RCT with a low risk of bias.

One randomised controlled trial recruited patients through their GPs (a total of 16 GP practices were involved which included 39 GPs) (Thomas, K. J., MacPherson, H., Ratcliffe, J. et al, 2005). Patients included had to be between the age of 18 and 65 (the mean age was 42) and have had non-specific low back pain for 4–52 weeks. They also had to have been assessed by their GP to check that primary care management was suitable. A total of 289 patients were identified and approached to join the study, of these 241 accepted and met the criteria. 160 were allocated to receive acupuncture and 81 were allocated to receive usual care, however, 1 patient from each group dropped out, 159 actually received acupuncture (146 were followed up at 3 months, 147 at 12 months and 123 and 24 months) and 80 received usual care (71 were followed up at 3 months, 68 at 12 months and 59 and 24 months).

Participants in the acupuncture group received 10 individualised acupuncture treatments over 3 months from one of 6 qualified acupuncturists. The usual care group received 10 NHS treatment sessions according the GPs assessment of the patients clinical need; this was a mixture of interventions, including drugs and recommended back exercises. Half the group also received physiotherapy or manipulation during the first three months. Both groups also received adjunctive care which included massage and advice on diet, rest and exercise. The results showed that acupuncture does give a greater long-term benefit compared to usual care. Acupuncture was significantly more effective in reducing pain at 24 months than usual care (P =0.032). The study also showed that traditional acupuncture care delivered in a primary care setting was safe and acceptable to patients with non-specific low back pain.

One concern with conduct of this trial was the decision to extend the follow-up to 24 months following interim analysis of the first 160 patients. Attrition was also quite high at 24 months follow-up, however, a similar pattern of attrition was observed in both groups therefore the risk of attrition bias is limited. This was a well conducted RCT with a low risk of bias.

One randomised controlled trial approached patients insured by one of the participating social health insurance funds if their physician viewed acupuncture appropriate for their chronic low back pain (Witt, Claudia M., Jena, Susanne, Selim, Dagmar et al, 2006). Those included had to be over the age of 18, have a clinical diagnosis of chronic low back pain with disease duration of more than 6 months, and have signed a written informed consent form. A total of 11630 patients met the criteria of the study, these were then randomized into three groups, 1451 to the acupuncture group, 1390 received acupuncture after a delay of 3 months and 8537 were randomised to the non-randomised acupuncture group.

Participants in the acupuncture group received up to 15 acupuncture sessions with disposable one-time needles and manual stimulation only, as well as usual care. Over the first 3 months, patients received a mean 10.4 sessions (standard deviation 3), with 74% receiving a total of 5–10 sessions. Other forms of acupuncture (e.g. laser acupuncture) were not permitted. The group receiving no acupuncture was given normal care. Participants in all three groups were allowed to use additional conventional treatments as needed. The results of the study showed that acupuncture, in addition to usual care, gave a clinically relevant benefit for pain, function and quality of life at 3 months among patients with chronic low back pain compared to usual care alone. The authors conclude that acupuncture should be considered a viable option in the management of patients with chronic LBP.

This was a RCT with a high risk of bias.

9.2.1.2. Neuroreflexotherapy (NRT)

One systematic review (Urrútia, G., Burton, A. K., Morral, A. et al, 2004) reviewed the effectiveness of NRT for the treatment of non-specific LBP in adult patients aged 16–65. NRT was defined as “temporary implantations of epidermal devices into trigger points at the site of each subject’s clinically involved dermatomes on the back and into referred tender points in the ear”. Patients with (sub)acute LBP (2–12 weeks) and/or chronic LBP (more than 12weeks) were included.

Two RCTs comparing NRT with sham-NRT show a statistically significant short-term positive effect on chronic back pain for the main outcomes of pain, ability to perform daily activities, and functional ability, as well as secondary outcomes of return to work, side effects and medication use. The effect appeared to be rapid and remained for at least 6 weeks after intervention in most of patients treated. One RCT of NRT as a supplement to standard management protocol for LBP in routine general practice show statistically significant short term (60 days) effect on pain relief (local and referred) and ability to perform daily activities, and on duration of sick leave and consumption of resources throughout the 1 year follow-up period.

NRT appears to be a safe and effective intervention for the short term treatment of chronic non specific LBP. However, the results are limited to trials conducted in one country by small number of specially trained practitioners

This was a well conducted systematic review with a low risk of bias.

9.2.1.3. Percutaneous Electrical Nerve Stimulation (PENS)

A randomised controlled trial (Hsieh, Ru Lan and Lee, Wen Chung, 2002) investigated the therapeutic effect of one shot of low-frequency PENS in patients visiting a rehabilitation clinic in Taiwan. A total of 133 patients received either (1) medication + PENS, (2) medication +TENS or (3) medication alone (control group). The duration of low-back back pain was not a specific inclusion criteria therefore patients had low-back pain of varying duration: 56% had acute LBP (< 1week), 20% had low back pain between 1week and 3 months, and 24% had chronic low back pain (> 3months).

Participants in the control group received medication only (including NSAID, diclofenac potassium, muscle relaxant and antacid), those in the medication+PENS group received one shot PENS treatment in addition to medication, and patients in the medication +TENS group received medication and one shot of TENS treatment. Results showed that one-shot PENS produces significant immediate pain relief effect, but that due to similar pain relief and functional disability improvements at 3 days and 1 week after treatment in the 3 groups, PENS does not have additional beneficial effects over medication alone after the immediate posttreatment periods.

This was a RCT with a high risk of bias

9.2.2. Health economics

Two studies were identified (Ratcliffe, J., Thomas, K. J., MacPherson, H. et al, 2006; Witt, Claudia M., Jena, Susanne, Selim, Dagmar et al, 2006). One study (Witt, Claudia M., Jena, Susanne, Selim, Dagmar et al, 2006) was excluded only because the setting was Germany and because it took a societal perspective. In the absence of a UK-based study it would have been included.

An economic evaluation (Ratcliffe, J., Thomas, K. J., MacPherson, H. et al, 2006) was conducted alongside an RCT of acupuncture for low back pain and the aim was to evaluate the cost-effectiveness of acupuncture in the management of persistent non-specific low back pain.

The study included 241 patients between the ages of 20 and 65 years, whose current episode of back pain was at least of 4 weeks duration and no longer than 12 months.

The acupuncture group could have up to 10 acupuncture treatments over 3 months. GPs were advised that they could give any additional care they thought necessary to patients in the acupuncture group. The usual care consisted of pragmatic GP management with no restrictions on the care they received.

The main outcome measure was incremental cost per QALY gained over 2 years. The number of QALYs gained was estimated using SF-36 data collected during the trial. This was converted to a single index value (SF-6D ) where 0 represents death and 1 perfect health. The costing perspective was that of the UK health service. Healthcare resources included those for: the acupuncture sessions, hospital inpatient stays, outpatient attendances, and primary care consultations. These resources were costed using national averages for England. Costs were reported in pounds sterling at 2002/2003 prices. Both costs and outcomes occurring during the 12–24-month period were discounted at 3.5%, the current recommended rate for public sector projects.

Results (base case)

The mean cost (Standard Deviation) of care for the acupuncture group was £460 (£376) compared to £345 (£550). The QALY gain for the acupuncture group over 24 months was 1.453 (0.248) compared to a mean of 1.426 (0.191) for the usual care group. The mean incremental health gain from acupuncture at 24 months was 0.027 QALYs, leading to a base case estimate of £4241 per QALY gained.

Sensitivity analysis

The study reported on three sensitivity analyses: 1) Imputing missing data relating to NHS costs or QALYs the ICER for acupuncture was £4209 at 24 months; 2) When patients who were permanently unable to work because of back pain were excluded (reason being that these patients would have higher costs and poorer outcomes) the ICER was £2104; and 3) By including lost productivity costs (from time off work with back pain) acupuncture treatment dominated usual care because of the overall cost savings from using acupuncture treatment.

This study shows that acupuncture for low back pain in primary care confers a modest health benefit for a modest increase in costs. The base case estimate is £4241 per QALY gained. Sensitivity analysis showed acupuncture to have a more than 90% chance of being cost effective at a £20,000 cost per QALY threshold. Including patient costs and the costs of lost productivity further strengthens the economics of acupuncture: that is, using a societal costing perspective acupuncture costs less and is more effective than usual care

These results are consistent with the findings from the Witt trial (Witt, Claudia M., Jena, Susanne, Selim, Dagmar et al, 2006).

9.2.3. Evidence statements for acupuncture needling

Evidence statementsEvidence to recommendations
Acupuncture:
9.2.3.1.

One systematic review reported some evidence reported some evidence reported some evidence for short-term pain relief from acupuncture compared to sham-therapy, and some evidence for pain and functional improvement from acupuncture compared to no treatment(1++) (Furlan, A. D., Van-Tulder, M. W., Cherkin, D. C. et al, 2005)

9.2.3.2.

One RCT found significant improvement in pain from acupuncture compared to no treatment, but not when comparing acupuncture and minimal acupuncture, at 52 weeks (1+)(Brinkhaus, B., Witt, C. M., Jena, S. et al, 2006)

9.2.3.3.

One well conducted RCT found that acupuncture was associated with an improvement in pain compared to conventional treatment, but that acupuncture didn’t have an effect on pain compared to sham-acupuncture, at 6 months (1+) (Haake, Michael, Müller, Hans Helge, Schade, Brittinger Carmen et al, 2007)

9.2.3.4.

One RCT found that acupuncture was associated with an improvement in pain, at 24 months, compared to usual care(1+) (Thomas, K. J., MacPherson, H., Ratcliffe, J. et al, 2005)

9.2.3.5.

One RCT showed that acupuncture was associated with significant improvements in back function, pain and quality of life, at 3 months, compared to no acupuncture (1−) (Witt, Claudia M., Jena, Susanne, Selim, Dagmar et al, 2006)

There is evidence that acupuncture needling (solid needling) is beneficial in reducing pain and improving function. No evidence of effect on psychological distress was found.
One paper (Thomas) consisted of population of interest, all the other papers included a population with LBP over longer duration than 12 months. The GDG agreed that it was appropriate to include those with recurring episodes of LBP which could include those whose last episode was longer than 12 months previously.
Evidence suggests that seeing an acupuncturist was better than usual care but that there is not much difference between acupuncture and sham. However, sham acupuncture is used as an active form of treatment by some practitioners, therefore this should be considered as a possible treatment. The strongest evidence comes from the Thomas paper who included the correct population and was well conducted. However, they extended the followup to 24 months which was not described in the protocol. The attrition rates were also high but they were similar between the two groups.
Three of the five studies describe duration of treatment as up to 10 sessions. Studies report short-term benefit.
A well-conducted UK based cost effectiveness analysis study showed acupuncture to be a cost effective treatment.
Number of treatments and duration were checked in the included studies. From this the group agreed a course comprised of up to 10 sessions over a period of up to 12 weeks.
GDG considered that further research on the effects on prolonged treatment was required.
Neuroreflexotherapy:
9.2.3.6.

One systematic review on neuroreflexotherapy showed NRT was associated with short-term improvement on pain and functional ability compared to sham-NRT, and short-term pain relief when used as supplement to standard care (1+) (Urrútia, G., Burton, A. K., Morral, A. et al, 2004)

All the studies included in the neuroreflexotherapy review had been conducted in a healthcare setting outside of UK and all from one centre. The three RCT’s included in the review also had small numbers.
This treatment is currently not routinely practised in UK. GDG agreed the evidence was not strong enough to recommend a change to current practice
PENS:
9.2.3.7.

One RCT on PENS showed no additional beneficial effect of PENS over medication alone, at 1 week (1−) (Hsieh, Ru Lan and Lee, Wen Chung, 2002)

Cost-effectiveness
9.2.3.8.

One NHS based costs per QALY analysis indicates that we can be 90% certain that acupuncture is cost-effective compared with usual care at 24 months using £20,000/QALY as the threshold of acceptability. (Ratcliffe, J., Thomas, K. J., MacPherson, H. et al, 2006) )

.

9.3. Injections

Clinical question: what is the effectiveness of injections or nerve blocks compared with usual care or sham on pain, functional disability or psychological distress?

9.3.1. Clinical evidence

Searches were conducted for any intramuscular, spinal, epidural or nerve block injections. Three studies were identified and included (2 systematic reviews and 1 RCT).

One systematic review of therapeutic facet joint interventions in chronic spinal pain included only one RCT relevant to our patient population (Boswell, Mark, V, Colson, James D., Sehgal, Nalini et al, 2007). The RCT is summarised below.

One randomised controlled trial (Carette, S., Marcoux, S., Truchon, R. et al, 1991) evaluated the efficacy of injections of corticosteroid into facet joints to treat chronic low back pain in a double-blind placebo-controlled trial. The design consisted of 2 phases: Phase 1 was designed to identify patients with chronic LBP whose pain was most likely to originate in the facet joints. Phase 2 evaluated the efficacy of injections of methylprednisolone acetate or isotonic saline in to the facet joints of patients whose back pain had been documented in phase 1 to originate in those joints. Patients were selected from a rheumatology outpatient clinic and had to be aged between 18 and 65 years and had LBP for at least 6 months. Normal neurological examination results were required. Exclusion criteria were presence of back pain from not a mechanical cause (e.g. tumour, infection, spondylitis), previous injections into facet joints or LBP surgery, pregnancy, known allergy to local anaesthetics and presence of blood coagulation disorder. A total of 190 patients were entered in Phase 1, following which 101 were entered into Phase 2, 51 in the methylprednisolone group, and 50 in the placebo group. Patients received either 20mg (1ml) of methylprednisolone acetate mixed with 1ml of isotonic saline or 2ml of isotonic saline in each of the facet joints previously injected in Phase 1, and were followed for 6 months. Outcomes of interest were VAS score, McGill pain questionnaire, finger-to-floor distance and Sickness Impact Profile score. Results showed that after 1 month, none of the outcome measures evaluating pain, functional status and back flexion differed clinically or statistically between the 2 groups; 42% of patients who received methylprednisolone and 33% of those who received placebo reported marked or very marked improvement (95% CI for the difference −11 to 28; P =0.53). At the 6 month evaluation, the patients with methylprednisolone reported more improvement, less pain on the VAS scale, and less physical disability. The differences were reduced, however, when concurrent interventions were taken into account. Moreover, only 22% of patients in the methylprednisolone group and 10% in the placebo group had sustained improvement from the first month to the 6th month (P =0.19). They concluded that injecting methylprednisolone acetate into the facet joint is of little value in the treatment of patients with chronic LBP.

This was a well conducted systematic review with a low risk of bias.

A systematic review by (Dagenais, S., Yelland, M. J., Del Mar, C. et al, 2007) aimed to assess the efficacy of prolotherapy in adults with chronic low back pain. Prolotherapy involves repeated injections of irritant solutions to strengthen lumbosacral ligaments in people with low back pain. The Cochrane library, MEDLINE, EMBASE, CINAHL and AMED databases were searched for RCTs on prolotherapy for patients with non-specific low back pain for more than 3 months. Outcomes of interest were pain, low-back related disability, well-being and return to work. Five RCTs were included in the review, four of which are relevant to this key clinical question. They included adult patients with LBP for over 6 months. Clinical heterogeneity amongst intervention groups and control groups prevented the study results from being pooled. Treatment injections were of glucose, glycerine and phenol lignocaine, whilst control injections were either lignocaine or saline.

The authors concluded that when used alone, prolotherapy is not an effective treatment for chronic low-back pain. This was a high quality systematic review with a very low risk of bias

One randomised controlled trial (Khot, Abhay, Bowditch, Mark, Powell, John et al, 2004) investigated the use of intradiscal steroid therapy in patients with discogenic LBP without radicular leg pain. Patients were recruited when they presented themselves to the study hospital (in the UK) with the signs and symptoms of discogenic low back pain without radicular leg pain. Other inclusion criteria were MRI findings showing degenerative disc disease and failure of at least 6 weeks of conservative treatment. Exclusions were medical conditions requiring systematic steroid therapy, sciatica, anatomical abnormalities, previous surgery and repeat injections. These patients were listed for discography, and if at discography there was concordant pain on pressurisation of a degenerate disc, the patient was randomized to the steroid or saline group, by opening a sealed envelope.

A total of 120 patients were included, 60 were injected with 1ml containing 40mg of methylprednisolone acetate, and 60 with normal saline. They were followed up to a year after the injections, in clinics and by postal questionnaire.

The study results showed that steroids are not effective in improving the clinical symptoms in this patient group (pain, disability) and that intradiscal steroid injections carried no benefit over a placebo saline injection. No information was given on the duration of low-back pain so the relevance of this RCT to this guideline and key clinical question is limited. This was a well conducted RCT with a low risk of bias

9.3.2. Health economics

No economic evaluations were identified for injection therapies or nerve blocks.

9.3.3. Evidence statements for injections and nerve blocks

Evidence statementsEvidence to recommendations
9.3.3.1.

A SR identified a RCT that met the inclusion criteria. It showed that facet-joint corticosteroid injections were not associated with any improvement in health outcomes at 1 month, and with improvement in pain at 6 months (however, the effect was reduced when concurrent interventions were taken into account). Overall conclusion was that facet-joint injections were of little value.(1+)(Boswell, Mark, V, Colson, James D., Sehgal, Nalini et al, 2007).

9.3.3.2.

One systematic review on prolotherapy found no effect on pain, disability or well being for patients with chronic low back pain(1++) (Dagenais, S., Yelland, M. J., Del Mar, C. et al, 2007)

9.3.3.3.

One RCT did not find any effect of intradiscal corticosteroid injections on the health outcomes of interest, compared to saline injections (1+)(Khot, Abhay, Bowditch, Mark, Powell, John et al, 2004)

9.3.3.4.

No cost effectiveness studies were identified for injections or nerve blocks

Searches were carried out to identify any form of injection for the lower back, however, only data on facet-joint, prolotherapy and intradiscal injections was identified.
The GDG agreed that there was a lack of evidence to recommend the use of these treatments and agreed by consensus injections were of no benefit for this population-.
Copyright © 2009, Royal College of General Practitioners.

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