***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: & NA ; The objective of the study was to examine the 1‐year cumulative incidence of episodic neck pain and to explore its associations with individual risk factors , including a history of previous neck injury . A baseline cross‐sectional survey of an adult general population sample made up of all 7669 adults aged 18–75 years , registered with two family practice s in South Manchester , United Kingdom , identified the study population of adults with no current neck pain . This study population was surveyed again 12 months later to identify all those who had experienced neck pain during the follow‐up period . At follow‐up , cumulative 1‐year episode incidence of neck pain was estimated at 17.9 % ( 95 % confidence interval 16.0–19.7 % ) . Incidence was independent of age , but was more common in women . A history of previous neck injury at baseline was a significant risk factor for subsequent neck pain in the follow‐up year ( risk ratio 1.7 , 95 % confidence interval 1.2–2.5 ) , independent of gender and psychological status . Other independent baseline risk factors for subsequent neck pain included number of children , poor self‐assessed health , poor psychological status and a past history of low back pain . We have carried out a prospect i ve study in a general population sample and demonstrated that established risk factors for chronic pain predict future episodes of neck pain , and shown that in addition a history of neck injury is an independent and distinct risk factor . This finding may have major public health and medicolegal implication Study Design . A question naire was mailed to 3000 r and omly selected 35‐45‐year‐old individuals in three communities in central Sweden . Objectives . To study the 1‐year prevalence of spinal pain and its ramifications in the form of pain , function , sick leave , and health care use . Summary of Background Data . Previous research ers have used a variety of definitions and population s , but primarily have investigated the occurrence of pain . Comprehensive data are needed concerning health care use , the degree of the pain problem , functional disturbances , and sick leave . Method . Participants in the study completed a question naire regarding spinal pain during the past year including the degree of their experienced pain , functional impairment , lost work days , and health care use . Results . A total of 2305 people ( 78.5 % ) responded to the question naire . Nonrespondents had similar characteristics but a slightly lower 1‐year prevalence rate than did respondents . For respondents , the prevalence of spinal pain during the past year was 66.3 % , with women having a slightly higher prevalence than men . Approximately 25 % of the respondents indicated that they had a substantial problem based on ratings of pain , functional impairment , and sick leave . Work absenteeism reported to the Public Social Insurance Office involved 19 % of those with pain , but an additional 15 % indicated unreported absenteeism . On average , those with pain visited health care providers three times during the past year , but a small number of those who experienced pain consumed large amounts of health care and illness benefits . An important gender difference was shown , such that when pain was at its worst , men took sick leave , whereas women sought health care . Conclusions . Taken together , these data indicate that spinal pain is common among 35‐45‐year‐old men and ‐ women , and that it is related to marked problems for approximately one fourth of those who experience pain . Gender differences exist in the pattern of sick leave and health care use , and a small proportion of those with pain consume very large amounts of the re sources . Consequently , there is a need for early , effective , preventive treatments Study Design . The efficacy of radiofrequency medial branch neurotomy to treat cervical zygapophysial joint pain from whiplash was compared prospect ively in litigants and nonlitigants . Objectives . 1 ) To assess the effect of monetary gain on treatment of zygapophysial joint pain in cervical whiplash . 2 ) To determine whether radiofrequency medial branch neurotomy is effective treatment for whiplash . Summary of Background Data . The influence of litigation on treatment outcome is a subject of controversy in both the medical and legal professions . This is the first study to examine this issue in a prospect i ve manner using a previously proven diagnostic and therapeutic method . Methods . Sixty patients with cervical whiplash who remained symptomatic after 20 weeks of conservative management were referred for radiofrequency cervical medial neurotomy .  The patients were classified as litigant or nonlitigant based on whether the potential for monetary gain via litigation existed . Each group underwent identical evaluation and treatment . Patients were observed for 1 year . Visual analogue scores and self-reported improvement were obtained before , immediately after , and 1 year after radiofrequency cervical medial neurotomy . Results . Forty-six patients completed the study . The overall reduction in cervical whiplash symptoms and visual analogue pain scores were significant immediately after treatment ( nonlitigants vs. litigants : 2.0 vs. 2.5 , P = 0.36 ) and at 1 year ( nonlitigants vs. litigants : 2.9 vs. 4.0 , P = 0.05 ) . One-year follow-up scores were higher than immediate post-treatment scores ( nonlitigants vs. litigants : 2.5 vs. 3.6 ) . The difference between litigants and nonlitigants in the degree of symptomatology or response to treatment did not reach significance . Conclusions . These results demonstrate that the potential for secondary gain in patients who have cervical facet arthropathy as a result of a whiplash injury does not influence response to treatment . These data contradict the common notion that litigation promotes malingering . This study also confirms the efficacy of radiofrequency medial branch neurotomy in the treatment of traumatic cervical facet arthropathy The effects from cervical facet joint injections in those patients who have been complaining cervical zygapophyseal joint pain were compared . The patients were diagnosed originally as myofascial pain syndrome ( MPS ) , cervical herniated nucleus pulposus ( HNP ) , and whiplash-associated disorders ( WAD ) . Patients with the zygapophyseal joints pain of C5 - 6 and C6 - 7 were classified by their pain origin as MPS , HNP , and WAD . All patients had been undergone cervical zygapophyseal joints injections with the mixture of lidocaine and triamcinolone unilaterally or bilaterally through the posterior approach under C-arm imaging guide . The therapeutic effects were compared with reduction of numeric rating scale ( NRS ) of pain before and immediately after blockade and symptom-free periods in each group after 12 months . Symptom duration s before injections were 16.1±9.6 , 4.6±1.9 and 4.1±1.1 months in each MPS , HNP , and WAD groups . The reductions of NRS immediately after the blockade among the three groups were not different . However , the symptom-free duration after blockade lasted longer in the HNP group than the other two groups . In patients with cervical zygapophyseal pain syndromes , the analgesic effect from cervical facet joint blocks lasted longer in cervical HNP than MPS or WAD BACKGROUND Chronic pain in the cervical zygapohyseal joints is a common problem after whiplash injury , but treatment is difficult . Percutaneous radiofrequency neurotomy can relieve the pain by denaturing the nerves innervating the painful joint , but the efficacy of this treatment has not been established . METHODS In a r and omized , double-blind trial , we compared percutaneous radio-frequency neurotomy in which multiple lesions were made and the temperature of the electrode making the lesions was raised to 80 degrees C with a control treatment using an identical procedure except that the radio-frequency current was not turned on . We studied 24 patients ( 9 men and 15 women ; mean age , 43 years ) who had pain in one or more cervical zygapophyseal joints after an automobile accident ( median duration of pain , 34 months ) . The source of their pain had been identified with the use of double-blind , placebo-controlled local anesthesia . Twelve patients received each treatment . The patients were followed by telephone interviews and clinic visits until they reported that their pain had returned to 50 percent of the preoperative level . RESULTS The median time that elapsed before the pain returned to at least 50 percent of the preoperative level was 263 days in the active-treatment group and 8 days in the control group ( P=0.04 ) . At 27 weeks , seven patients in the active-treatment group and one patient in the control group were free of pain . Five patients in the active-treatment group had numbness in the territory of the treated nerves , but none considered it troubling . CONCLUSIONS In patients with chronic cervical zygapophyseal-joint pain confirmed with double-blind , placebo-controlled local anesthesia , percutaneous radio-frequency neurotomy with multiple lesions of target nerves can provide lasting relief OBJECTIVE To determine the long-term efficacy of percutaneous radiofrequency medial branch neurotomy in the treatment of  chronic neck pain .  METHODS Between 1991 and 1996 , radiofrequency neurotomy was performed in 28 patients diagnosed as having cervical zygapophysial joint pain on the basis of controlled diagnostic blocks . The procedure was repeated in patients whose pain recurred . Outcome measures were the proportion of patients who responded to the initial procedure and the duration of relief subsequently obtained . Outcome was correlated with the operator performing the procedure , the type of electrode used , litigation status , and the type of diagnostic blocks used to establish the diagnosis . RESULTS Complete relief of pain was obtained in 71 % of patients after an initial procedure . No patient who failed to respond to a first procedure responded to a repeat procedure , but if pain returned after a successful initial procedure , relief could be reinstated by a repeat procedure . The median duration of relief after a first procedure was 219 days when failures are included but 422 days when only successful cases are considered . The median duration of relief after repeat procedures was at least 219 days ; several patients had ongoing relief at the time of follow-up . Outcome did not differ according to the operator , the type of electrode used , litigation status , or the type of diagnostic block used . CONCLUSION Radiofrequency neurotomy provides clinical ly significant and satisfying periods of freedom from pain , and its effects can be reinstated if pain recurs The CONSORT ( Consoli date d St and ards of Reporting Trials ) Statement , including a checklist and a flow diagram , was developed to help authors improve their reporting of r and omized controlled trials . Its primary focus was on individually r and omized trials with 2 parallel groups that assess the possible superiority of one treatment compared with another but is now being extended to other trial design s. Noninferiority and equivalence trials have method ological features that differ from superiority trials and present particular difficulties in design , conduct , analysis , and interpretation . Although the rationale for such trials occurs frequently , those design ed and described specifically as noninferiority or equivalence trials appear less commonly in the medical literature . The quality of reporting of those that are published is often inadequate . In this article , we present an adapted CONSORT checklist  for reporting noninferiority and equivalence trials and provide illustrative examples and explanations for those items amended from the original CONSORT checklist . The intent is to improve reporting of noninferiority and equivalence trials , enabling readers to assess the validity of their results and conclusions BACKGROUND R and omized controlled trials in research setting s have demonstrated the efficacy of percutaneous radiofrequency neurotomy of the medial branches of the cervical dorsal rami in the palliation of chronic zygapophysial joint pain , a common cause of chronic neck pain , but one that is under-recognized in some quarters . AIMS This study aim ed to determine the outcomes of radiofrequency neurotomy in usual clinical practice for patients with established cervical zygapophysial joint pain . METHODS The study was conducted in a public hospital , incorporating the private practice and public clinic elements of a single physician . All patients who underwent radiofrequency neurotomy had a diagnosis of cervical zygapophysial joint pain established by controlled cervical medial branch blocks . The primary outcome of duration of pain relief was determined for all consecutive procedures performed during a two-year period . Data were collected by chart review and telephone contact by an independent assessor . RESULTS Forty-seven procedures were performed on 35 patients . Two patients were lost to follow-up . Twelve patients had two procedures . Thirty-six of 45 assessable procedures ( 80 % ) achieved significant pain relief . These 36 procedures achieved a mean duration of pain relief of 36 weeks , with a median of 35 weeks . Repeat procedures usually achieved reproducible pain relief . Most patients had significant postprocedural pain for about one week . Only one serious adverse event ( local superficial infection ) was reported . CONCLUSION Radiofrequency neurotomy is an effective palliative treatment for chronic cervical zygapophysial joint pain when performed in routine clinical practice Study Design . Population ‐based , cross‐sectional mailed survey . Objective . To determine the lifetime , period , and point prevalence of neck pain and its related disability among Saskatchewan adults and investigate the presence and strength of nonresponse bias . Summary of Background Data . In Europe , the life‐time and point prevalence of neck pain is almost as high as the prevalence of low back pain . Similarly , chronic neck pain is highly prevalent and a common source of disability in the working‐age population . However , no studies specifically have documented the prevalence of neck pain and its related disability in North America . Methods . The Saskatchewan Health and Back Pain Survey was mailed to 2184 r and omly selected Saskatchewan adults aged 20‐69 years . Fifty‐five percent of the study population participated . The presence of nonresponse bias was investigated through logistic regression and wave analysis . The Chronic Pain Question naire was used to classify the severity of chronic neck pain . Results . The age‐st and ardized lifetime prevalence of neck pain is  
    Output:
    
The indicated evidence for radiofrequency neurotomy in the cervical spine is Level II-1 or II-2 , whereas the evidence is lacking for intraarticular injections .
The indicated evidence for therapeutic facet joint interventions is Level II-1 for medial branch blocks , and Level II-1 or II-2 for radiofrequency neurotomy