***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: OBJECTIVE --To assess the responsiveness of the SF 36 health survey question naire to changes in health status over time for four common clinical conditions . DESIGN --Postal question naires at baseline and after one year 's follow up , with two reminders at two week intervals if necessary . SETTING --Clinics and four training general practice s in Grampian region in the north east of Scotl and . PATIENTS --More than 1,700 patients aged 16 to 86 years with one of four conditions : low back pain , menorrhagia , suspected peptic ulcer , and varicose veins ; and a r and om sample of 900 members of the local general population for comparison . MAIN MEASURES --A transition question measuring change in health and the eight scales of the SF 36 health survey question naire ; st and ardised response means ( mean change in score for a scale divided by the st and ard deviation of the change in scores ) used to quantify the instrument 's responsiveness to changes in perceived health status , and comparison of patient scores at baseline and follow up with those of the general population . RESULTS --The response rate exceeded 75 % in a patient population . Changes across the SF 36 question naire were associated with self reported changes in health , as measured by the transition question . The question naire showed significant improvements in health status for all four clinical conditions , whether in referred or non-referred patients . For patients with suspected peptic ulcer and varicose veins the SF 36 profiles at one year approximate to the general population . CONCLUSIONS --These results provide the first evidence of the responsiveness of the SF 36 question naire to changes in perceived health status in a patient population in the United Kingdom OBJECTIVE --To develop a valid and reliable outcome measure for patients with varicose veins . DESIGN --Postal question naire survey of patients with varicose veins . SETTING --Surgical outpatient departments and training general practice s in Grampian region . SUBJECTS--373 patients , 287 of whom had just been referred to hospital for their varicose veins and 86 who had just consulted a general practitioner for this condition and , for comparison , a r and om sample of 900 members of the general population . MAIN MEASURES --Content validity , internal consistency , and criterion validity . RESULTS --281(76 % ) patients ( mean age 45.8 ; 76 % female ) and 542(60 % ) of the general population ( mean age 47.9 ; 54 % female ) responded . The question naire had good internal consistency as measured by item-total correlations . Factor analysis identified four important health factors : pain and dysfunction , cosmetic appearance , extent of varicosity and complications . The validity of the question naire was demonstrated by a high correlation with the SF-36 health profile , which is a general measure of patients ' health . The perceived health of patients with varicose veins  , as measured by the SF-36 , was significantly lower than that of the sample of the general population adjusted for age and a lower proportion of women . CONCLUSION --A clinical ly derived question naire can provide a valid and reliable tool to assess the perceived health of patients with varicose veins . IMPLICATION S -- The question naire may be used to justify surgical treatment of varicose veins Introduction No existing patient-reported outcome instrument focuses solely on assessment of varicose veins symptoms that are bothersome to patients . Methods The VVSymQ ® instrument is a five-item patient-reported outcome that assesses symptoms most important to patients with varicose veins  ( heaviness , achiness , swelling , throbbing and itching ) . This paper describes how the VVSymQ ® instrument was incorporated into an electronic daily diary to monitor key outcomes over time and capture treatment benefit in two r and omized , controlled , phase 3 clinical trials . Results Patients were highly compliant in completing the electronic daily diary , and the VVSymQ ® instrument demonstrated ability to detect overall change and ability to detect change that is meaningful to patients . Conclusion The VVSymQ ® instrument is a reliable , valid instrument responsive to measuring change in the patient experience of varicose vein symptoms pre- and post-intervention , and is uniquely focused on patient-reported symptoms compared with other widely used question naires completed by clinicians We present data from two studies which clarify the relationship between the responsiveness and validity of instruments design ed to measure health status in clinical trials . In a controlled trial of  long vs short duration adjuvant chemotherapy for women with Stage II breast cancer , the Breast Cancer Chemotherapy Question naire ( BCQ ) proved valid as a measure of subjective health status and was able to distinguish long vs short arms . Well vali date d measures of physical and emotional function developed by the R and Corporation were unable to distinguish between the two groups . The Eastern Co-operative Oncology Group Criteria ( ECOG ) distinguished the two groups , but failed criteria of clinical sensibility as a measure of subjective health status . In a study of patients with Crohn 's disease and ulcerative colitis , the Inflammatory Bowel Disease Question naire ( IBDQ ) showed small intrasubject variability over time . Gobal ratings of change showed moderate to high correlations with changes in IBDQ score , and patients who reported overall improvement or deterioration showed large changes in IBDQ score . Each of these findings support , in different ways , the reproducibility , validity , and responsiveness of the question naire . While the same data can at times bear on both validity and responsiveness , when assessing evaluative instruments it is useful to make a conceptual distinction between the two Objectives The  venous clinical severity score  ( VCSS ) and the Aberdeen varicose vein question naire ( AVVQ ) improve after treating chronic venous insufficiency ( CVI ) . The aim was to examine how and why they improve by evaluating the change in each individual question . Methods This was an analysis on prospect ively collected data from a clinical study on 100 patients ( 58 % female ) with CVI ( C2 = 34 , C3 = 14 , C4a = 29 , C4b = 9 , C5 = 7 , C6 = 7 ) who were r and omized to endovenous laser ablation ( n = 50 ) or foam sclerotherapy ( n = 50 ) . The change scores ( performance ) of each question of the VCSS ( questions 1–10 ) and the AVVQ ( questions 1–13 ) were calculated by subtracting the score at three weeks , and three months , from the pre-treatment score . Results Both the median , interquartile range ( IQR ) , VCSS and the AVVQ scores improved from 6 ( 4 ) and 21.4 ( 15.1 ) at baseline to 3 ( 4 ) and 18.6 ( 12.1 ) at three weeks ( P < 0.0005 , P = 0.031 ) to 2 ( 3 ) and 8.8 ( 13.6 ) at three months , ( P < 0.0005 , P < 0.0005 ) , respectively . The performance of the first three questions of the VCSS ( pain , extent of varicosities , oedema ) were the most contributory to the overall score . Questions 5 , 7 , 8 , 9 on ulceration improved the most individually but did not contribute significantly to the overall score . Questions 5 , 9 of the  AVVQ  on stocking use and ulceration failed to contribute statistically to the overall improvement at three months . Conclusion The majority of the individual questions of the VCSS and AVVQ responded to change . However , the cause of a poor response was multifactorial with statistical dilution playing a significant role . Stratification of patients according to ulceration may allow better comparisons Antimicrobial silver dressings are used beneath graduated compression in the treatment of venous ulceration . There is little information on whether their use is effective . This was a prospect i ve r and omized trial and cost‐effectiveness analysis of silver‐donating versus non‐silver low‐adherence dressings in the treatment of venous leg ulcers STUDY OBJECTIVE s : To develop and vali date a patient-based outcome measure to evaluate symptoms in patients with community-acquired pneumonia ( CAP ) . DESIGN A psychometric study within an international , prospect i ve , r and omized , double-blind study . The CAP-symptom question naire ( CAP-Sym ) is a new , 18-item , patient-reported outcome measure that evaluates the bothersomeness of CAP-related symptoms during the past 24 h using a 6-point Likert scale . We used " gold st and ard " psychometric methods to comprehensively evaluate the acceptability , reliability , validity , and responsiveness of the CAP-Sym . SETTING Sixty-four centers in 13 countries ( France , Germany , Hungary , Israel , Italy , Norway , Pol and , Portugal , South Africa , Spain , Sweden , Switzerl and , United Kingdom ) . PATIENTS Five hundred fifty-six patients with CAP , recruited from outpatient clinics , general practice , and hospital centers . INTERVENTIONS R and omization 1:1 to moxifloxacin ( 400 mg once daily ) , oral or st and ard oral treatment ( amoxicillin , 1 g tid , or clarithromycin , 500 mg bid ) , alone or in combination , for up to 14 days . RESULTS St and ard psychometric tests confirmed the acceptability ( item nonresponse , item-endorsement frequencies , item/scale floor and ceiling effects ) , reliability ( internal consistency , item-total and inter-item correlations , test-retest reliability ) , validity ( content , construct , convergent , discriminant , known groups ) , and responsiveness of the CAP-Sym . CONCLUSIONS The CAP-Sym is a practical and scientifically sound patient-based outcome measure of CAP-related symptoms that has been developed using " gold st and ard " methods . As the only fully vali date d measure of symptoms in patients with CAP , which is quick and easy to administer and is more responsive than the generic Medical Outcomes Study 36-Item Short-Form Health Survey , the CAP-Sym provides a practical and rigorous method for improving the evaluation of outcomes in clinical trials and audit PURPOSE The prevalence of reflux in the deep and superficial venous systems in the Edinburgh population and the relationship between patterns of reflux and the presence of venous disease on clinical examination were studied . METHODS A cross-sectional survey was done on men and women ranging in age from 18 to 64 years , r and omly selected from 12 general practice s. The presence of varicose veins and chronic venous insufficiency was noted on clinical examination , as was the duration of venous reflux by means of duplex scanning in 8 vein segments on each leg . Results were compared using cut-off points for reflux duration ( RD ) of 0.5 seconds or more ( RD > /= 0.5 ) and more than 1.0 second ( RD > 1.0 ) to define reflux . RESULTS There were 1566 study participants , 867 women and 699 men . The prevalence of reflux was similar in the right and left legs . The proportion of participants with reflux was highest in the lower thigh long saphenous vein ( LSV ) segment ( 18.6 % in the right leg and 17.5 % in the left leg for RD > /= 0.5 ) , followed by the above knee popliteal segments ( 12.3 % in the right leg and 11.0 % in the left leg for RD > /= 0.5 ) , the below knee popliteal ( 11.3 % in the right leg and 9.5 % in the left leg for RD > /= 0.5 ) , upper LSV ( 10.0 % in the right leg and 10.8 % in the left leg for RD > /= 0.5 ) segments , the common femoral vein segments ( 7.8 % in the right leg and 8.0 % in the left leg for RD > /= 0.5 ) , the lower superficial femoral vein ( SFV ) segments ( 6.6 % in the right leg and 6.4 % in the left leg for RD > /= 0.5 ) , and the upper SFV ( 5.2 % in the right leg and 4.7 % in the left leg for RD > /= 0.5 ) and short saphenous vein ( SSV ) ( 4.6 % in the right leg and 5.6 % in the left leg for an RD > /= 0.5 ) segments . In the superficial vein segments , there was little difference in the occurrence of reflux whether RD > /= 0.5 or RD > 1.0 was used ; but in the different deep vein segments , the prevalence of reflux was 2 to 4 times greater for RD > /= 0.5 rather than RD > 1.0 . Men had a higher prevalence of reflux in the deep vein segments than women , reaching statistical significance ( P < /=.01 ) in 4 of 5 segments for RD > /= 0.5 . In general , the prevalence of reflux increased with age . Those with " venous disease " had a significantly higher prevalence of reflux in all vein segments than those with " no disease " ( P < /=.001 ) . CONCLUSION The prevalence of venous reflux in the general population was related to the presence of " venous disease , " although it was also present in those without clinical ly apparent disease . There was a higher prevalence of reflux in the deep veins in men than the deep veins in women . Follow-up study of the population will determine the extent to which reflux is a predictor of future disease and complications 
    Output:
    
The evidence from included studies provided data to support the construct validity , test-retest reliability and responsiveness of the AVVQ .
However , its content validity , including weighting of the AVVQ questions , was biased and based on the opinion of clinicians , and the instrument had poor acceptability .
VVSymQ ® displayed good responsiveness and acceptability rates .
SF-36 ® was considered to have satisfactory responsiveness and internal consistency .
There is a scarcity of psychometric evidence for PROMs used in patients with varicose veins .
These data suggest that AVVQ and SF-36 ® are the most rigorously evaluated PROMs in patients with varicose veins