***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: The number of published systematic review s of studies of healthcare interventions has increased rapidly and these are used extensively for clinical and policy decisions . Systematic review s are subject to a range of biases and increasingly include non-r and omised studies of interventions . It is important that users can distinguish high quality review s. Many instruments have been design ed to evaluate different aspects of review s , but there are few comprehensive critical appraisal instruments . AMSTAR was developed to evaluate systematic review s of r and omised trials . In this paper , we report on the updating of AMSTAR and its adaptation to enable more detailed assessment of systematic review s that include r and omised or non-r and omised studies of healthcare interventions , or both . With moves to base more decisions on real world observational evidence we believe that AMSTAR 2 will assist decision makers in the identification of high quality systematic review s , including those based on non-r and omised studies of healthcare interventions Background Clinical trials suggest that cyclo-oxygenase-2 specific inhibitors ( coxibs ) are an effective treatment for acute postoperative pain . The aims of this systematic review were to examine the evidence for oral valdecoxib and injected parecoxib , and quantify efficacy and adverse effects . Methods Information from r and omized , double-blind studies in acute postoperative pain was sought . The area under the pain relief versus time curve over four to six hours was dichotomized using vali date d equations to derive the proportion of patients with treatment and  placebo with at least 50 % pain relief over four to six hours and calculate the number-needed-to-treat ( NNT ) . Information on duration of analgesia and adverse events was also collected . Results The NNT for one patient to experience at least 50 % relief over six hours following a single oral dose of valdecoxib 20 mg and 40 mg was 1.7 ( 1.4 to 2.0 ) and 1.6 ( 1.4 to 1.8 ) respectively . The NNT for one patient to have at least 50 % relief over four to six hours with parecoxib 20 mg IV and 40 mg IV was 3.0 ( 2.3 to 4.1 ) and 2.3 ( 2.0 to 2.6 ) respectively . Mean time to remedication ( weighted by trial size ) was > 24 hours with valdecoxib 40 mg , 8.7 hours with parecoxib 40 mg IV and 1.7 to 1.8 hours with placebo . There were no statistical differences between treatment and placebo for any adverse effect . Conclusion Both oral valdecoxib and injected parecoxib are effective treatments for acute postoperative pain BACKGROUND For patients with surgical third molar removal , it is unknown what constitutes a clinical ly important change in patients ' visual analogue scale ( VAS ) reports of pain intensity . OBJECTIVES To determine what constitutes a clinical ly important change in pain intensity on a VAS following surgical removal of the third molar . METHODS The study population consisted of patients participating in three r and omized trials . Patients were asked to rate their pain three times per day over a period of seven days on a 100 mm VAS after surgical removal of the third molar . Global Perceived Effect was measured on day 1 and day 7 and was used as the external criterion for assessing clinical ly important pain reduction . Global Perceived Effect scores of 6 ( ' much improved ' ) or higher were classified as clinical ly ' successful ' , and scores of 5 ( ' slightly improved ' ) or below were classified as clinical ly ' unsuccessful ' . For each trial , the mean absolute and relative changes in VAS scores were calculated for both ' successful ' and ' unsuccessful ' treatments . Sensitivity and specificity analyses were performed . RESULTS The patients who reported ' successful ' pain reduction showed a relative pain reduction of ≥69 % and an absolute pain reduction > 2.5 cm on the VAS , whereas patients who classified their pain reduction as ' unsuccessful ' had a relative pain reduction of ≤18.5 % and an absolute pain reduction < 0.5 cm on the VAS . Furthermore , sensitivity and specificity analyses showed that a cut-off point of ≥50 % relative pain reduction exhibited the best balance of sensitivity and specificity . CONCLUSION Relative pain reduction of ≥50 % and an absolute pain reduction of ≥2.5 cm on the VAS were most accurate in predicting a successful pain reduction after a given treatment 
    Output:
    
The data identified combinations of ibuprofen and acetaminophen as having the highest association with treatment benefit in adult patients and the highest proportion of adult patients who experienced maximum pain relief .
Diflunisal , acetaminophen , and oxycodone were found to have the longest duration of action in adult patients .
Medication and medication combinations that included opioids were among those associated most frequently with acute adverse events in both child and adult-aged patient population s. PRACTICAL IMPLICATION S The best available data suggested that the use of nonsteroidal medications , with or without acetaminophen , offered the most favorable balance between benefits and harms , optimizing efficacy while minimizing acute adverse events