human
***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 examine self-reported health care use and health care-seeking behaviour of patients meeting DSM-IV 's diagnostic criteria for generalized anxiety disorder ( GAD ) . DESIGN Survey of out patients recruited at three different times of the day  using question naires on worry and anxiety ( a six-item screening question naire based on DSM-IV criteria for GAD ) , on perceived health problems , and on health care use and health care-seeking behaviour . The assessment package also included well vali date d assessment instruments for insomnia and depression symptoms .  All patients seeking health care were invited to participate . Participants completed the survey as they waited in the reception area . SETTING Four r and omly selected community-based medical clinics of Quebec city 's metropolitan area . PARTICIPANTS A final sample of 1110 patients among 1878 out patients invited to participate included 219 ( 19.7 % ) who tested positive for GAD . MAIN OUTCOME MEASURES Self-reported worry and anxiety ( based on DSM-IV criteria for GAD ) , self-perceived health problems , health care use and health care-seeking behaviour , insomnia , and symptoms of depression . RESULTS Participants who tested positive on a screening test for GAD reported more annual medical visits ( 5.3 versus 3.4 ) than other patients . Those who reported at least five annual medical visits were nearly four times more likely to have positive results for GAD . Women were 1.6 times more likely to have positive results than men were . Patients who tested positive reported insomnia-type sleep disturbances , depressive symptoms , fatigue , and gastric problems significantly more often than others . Forty-two percent had consulted a family physician in the past year with a complaint of anxiety . Eighty percent of patients who tested positive reported they believed they had an anxiety problem , and this belief predicted positive test results ( odds ratio = 20.3 ) . Yet most reported not having sought other types of medical or psychological care specifically for anxiety in the past year . CONCLUSION Some patients in this sample with symptoms of GAD mainly seek primary care for their symptoms . Questions about excessive worrying and anxiety , as part of routine examination , can increase recognition of GAD INTRODUCTION Tiredness is a common presentation in general practice for which pathology tests are commonly ordered . Our aim was to study their utilisation for tiredness . METHODS We examined an integrated data base which contains the medical records for 58,139 patients and their 696,518 associated general practitioner encounters . Three hundred and forty-two patients and their 1652 associated encounters were r and omly selected out of 12,291 patients and their 26,748 associated encounters that had mentioned tiredness ( or a synonym ) . RESULTS One hundred and eighty-one patients ( 53 % ) had at least one pathology test ordered at any time in their episode of care . Patients over 60 years of age , patients who consulted their GP more than once and patients without comorbidity were more likely to have a pathology test ordered . Only 12 patients ( 3 % ) had a significant clinical diagnosis based on an abnormal pathology test . CONCLUSION Pathology testing for patients presenting with tiredness is high . Most tests do not yield a significant clinical diagnosis OBJECTIVE --To describe the characteristics of patients attending their general practitioners and complaining of fatigue or being " tired all the time . " DESIGN -- Prospect i ve study of cohort aged 16 years and older with follow up at two weeks and by question naires at two and six months . SUBJECTS--220 patients ( 164 women ) with mean age 43 years and an age-sex matched comparison group . SETTING S -- Doctors and patients in four practice s in Lancashire , Mid Glamorgan , Suffolk , and Surrey . MAIN OUTCOME MEASURES --General clinical data , results from st and ard group of laboratory tests , fatigue question naire , and 12 item general health question naire . RESULTS --Over twice as many patients with fatigue had high scores on the health question naire compared with the comparison group ( 156 ( 75 % ) v 69 ( 34 % ) ) . Results of laboratory tests were abnormal and contributed to the diagnosis in 19 patients . 59 out of 102 patients who responded had high fatigue scores six months later . Patients with persistent fatigue were more likely to have a history of anxiety or depression and to have had fatigue for more than three months on entry to the study . CONCLUSIONS --Women are particularly at risk of fatigue . The outcome is better if patients have had symptoms for three months or less or there is no history of emotional illness BACKGROUND Unexplained fatigue is frequently encountered in general practice . Because of the low prior probability of underlying somatic pathology , the positive predictive value of abnormal ( blood ) test results is limited in such patients . AIM The study objectives were to investigate the relationship between established diagnoses and the occurrence of abnormal blood test results among patients with unexplained fatigue ; to survey the effects of the postponement of test ordering on this relationship ; and to explore consultation-related determinants of abnormal test results . DESIGN OF STUDY Cluster r and omised trial . SETTING General practice s of 91 GPs in the Netherl and s. METHOD GPs were r and omised to immediate or postponed blood-test ordering .  Patients with new unexplained fatigue were included . Limited and exp and ed sets of blood tests were ordered either immediately or after 4 weeks . Diagnoses during the 1-year follow-up period were extracted from medical records . Two-by-two tables were generated . To establish independent determinants of abnormal test results , a multivariate logistic regression model was used . RESULTS Data of 325 patients were analysed ( 71 % women ; mean age 41 years ) . Eight per cent of patients had a somatic illness that was detectable by blood-test ordering . The number of false-positive test results increased in particular in the exp and ed test set . Patients rarely re-consulted after 4 weeks . Test postponement did not affect the distribution of patients over the two-by-two tables . No independent consultation-related determinants of abnormal test results were found . CONCLUSION Results support restricting the number of tests ordered because of the increased risk of false-positive test results from exp and ed test sets . Although the number of re-consulting patients was small , the data do not refute the advice to postpone blood-test ordering for medical reasons in patients with unexplained fatigue in general practice To determine the psychiatric morbidity of patients complaining of chronic fatigue , we undertook a prospect i ve evaluation of 100 adults ( 65 women and 35 men ; mean age , 41 years ; and mean duration of chronic fatigue , 13 years ) . The study was conducted in an internal medicine outpatient clinic . In addition to a comprehensive medical evaluation , the patients were administered the 260-item Diagnostic Interview Schedule  , a highly structured instrument that enabled the physician-interviewer to make accurate psychiatric diagnoses . A thorough follow-up examination was given an average of 8.4 months later . Sixty-six patients had one or more psychiatric disorders that were considered a major cause of their chronic fatigue ( mood disorder , 47 patients ; somatization disorder , 15 patients ; and anxiety disorder , nine patients ) . Five patients had medical conditions that were considered a major cause of their fatigue . The complaint of chronic fatigue remained unexplained in 31 patients . In this prospect i ve study , two thirds of cases of chronic fatigue appeared to be caused by psychiatric disorders . A thorough evaluation of the mental health of patients complaining of chronic fatigue could therefore provide pharmacologic and psychotherapeutic approaches and avoid unnecessary and costly medical investigations and therapies BACKGROUND Early diagnosis of cancer is an important challenge in general practice . Symptoms are the most common starting points . OBJECTIVE To assess the association between symptoms presented and subsequent cancer . DESIGN A cohort study of all patients seen consecutively by GPs . Prospect i ve recording of cancer diagnosis , new cancer or new recurrence . SETTING Two hundred and eighty-three general practice surgeries and 10 working days . METHOD During patient consultations , GPs registered seven focal symptoms and three general symptoms , commonly considered as warning signs of cancer ( WSC ) . Follow-up 6 - 11 months later with registration of any subsequent diagnosis of cancer was done . RESULTS Of 51 073 patients , 6321 ( 12.4 % ) had recordings of 7704 WSC . During a median follow-up period of 8 months , 263 patients were diagnosed with cancer and 59 of them with recurrence of a previously diagnosed cancer . Of the cancer patients , 106 ( 40 % ) had presented one or more WSC during a preceding consultation . Examined symptoms had likelihood ratios for cancer from 1.5 to 8.2 and positive predictive values ( PPVs ) from 0.8 % to 3.8 % . Limited to older age groups , PPVs were a little higher . General symptoms were rarely associated with cancer unless a focal symptom had been recorded as well . Multiple symptoms increased the probability of cancer . CONCLUSION 12.4 % of GP patients presented with WSC  .  A general symptom may have cancer diagnostic value , but usually , only when it occurs along with a focal symptom . PPV of any single symptom is low , and decisions about referral require additional information Background : Little is known about the distribution of diagnoses that account for fatigue in patients in primary care . We evaluated the diagnoses established within 1 year after presentation with fatigue in primary care that were possibly associated with the fatigue . Methods : We conducted a prospect i ve observational cohort study with 1-year follow-up . We included adult patients who presented with a new episode of fatigue between June 2004 and January 2006 . We extracted data on diagnoses during the follow-up period from the patients ’ medical records as well as data on pre-existing chronic diseases . Results : Of the 571 patients for whom diagnostic data were available , 268 ( 46.9 % ) had received one or more diagnoses that could be associated with fatigue . The diagnoses were diverse and mostly included symptom diagnoses , with main categories being musculoskeletal ( 19.4 % ) and psychological problems ( 16.5 % ) . Clear somatic pathology was diagnosed in 47 ( 8.2 % ) of the patients . Most diagnoses were not made during the consultation when fatigue was presented . Interpretation : Only a minority of patients were diagnosed with serious pathology . Half of the patients did not receive any diagnosis that could explain their fatigue . Nevertheless , because of the wide range of conditions and symptoms that may explain or co-occur with the fatigue , fatigue is a complex problem that deserves attention not only as a symptom of underlying specific disease BACKGROUND Chronic fatigue syndrome ( CFS ) has been defined , but many more patients consult in primary care with chronic fatigue that does not meet the criteria for CFS . General practitioners ( GPs ) do not generally use the CFS diagnosis , and have some doubt about the validity of CFS as an illness . AIM To describe the proportion of patients consulting their GP for fatigue that met the criteria for CFS , and to describe the social , psychological , and physical differences between patients with CFS and those with non-CFS chronic fatigue in primary care . DESIGN OF STUDY Baseline data from a trial of complex interventions for fatigue in primary care . SETTING Twenty-two general practice s located in London and the South Thames region of the United Kingdom recruited patients to the study between 1999 and 2001 . METHOD One hundred and forty-one patients who presented to their GP with unexplained fatigue lasting six months or more as a main symptom were recruited , and the Centers for Disease Control ( CDC ) case definition was applied to classify CFS . RESULTS Approximately two-thirds ( 69 % ) of patients had chronic fatigue  and not CFS . The duration of fatigue ( 32 months ) and perceived control over fatigue were similar between groups ; however , fatigue , functioning , associated symptoms , and psychological distress were more severe in the patients in the CFS group , who also consulted their GP significantly more frequently , were twice as likely to be depressed , and more than twice as likely to be unemployed . About half ( CFS = 50 % ; chronic fatigue = 55 % ) in each group attributed their fatigue to mainly psychological causes . CONCLUSIONS In primary care , CFS is a more severe illness than chronic fatigue , but non-CFS chronic fatigue is associated with significant fatigue and is reported at least twice as often . That half of patients , irrespective of CFS status , attribute their fatigue to psychological causes , more than is observed in secondary care , indicates an openness to the psychological therapies provided in that setting . More evidence on the natural history of chronic fatigue and CFS in primary care is required , as are trials of complex interventions . The results may help determine the usefulness of differentiating between chronic fatigue and CFS BACKGROUND The symptom iceberg describes the phenomenon that most symptoms are managed in the community without people seeking professional health care . The size of the iceberg for many symptoms is unknown , as is their association with personal characteristics , including history of a chronic disease . AIM To ascertain the size of the symptom iceberg in the UK . DESIGN OF STUDY A UK-wide community-based postal survey . SETTING Urban and rural communities across the UK . METHOD A postal survey was sent to an age- and sex-stratified r and om sample of 2474 adults , aged 18 - 60 years , drawn from 20 practice s around the UK . Questions were aim ed at investigating adults ' experiences of 25 different symptoms in the previous 2 weeks . RESULTS The number of symptoms experienced by one individual in the previous 2 weeks ranged from 0 to 22 ( mean 3.66 ) . Of the symptoms examined , the three most common were : feeling tired/run down ; headaches ; and joint pain . Univariate analysis found symptom prevalence to be significantly associated with a wide range of participant characteristics . However , after 
    Output:
    
agent
Pooling was not appropriate for CFS.In studies with control groups of patients without the symptom of tiredness , prevalence of somatic disease was identical to those complaining of tiredness .
Depression , however , was more frequent among those with tiredness .
Conclusions Serious somatic disease is rare in patients complaining of tiredness .
Since prevalence is similar in patients without tiredness , the association may not be causal .
***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 examine self-reported health care use and health care-seeking behaviour of patients meeting DSM-IV 's diagnostic criteria for generalized anxiety disorder ( GAD ) . DESIGN Survey of out patients recruited at three different times of the day  using question naires on worry and anxiety ( a six-item screening question naire based on DSM-IV criteria for GAD ) , on perceived health problems , and on health care use and health care-seeking behaviour . The assessment package also included well vali date d assessment instruments for insomnia and depression symptoms .  All patients seeking health care were invited to participate . Participants completed the survey as they waited in the reception area . SETTING Four r and omly selected community-based medical clinics of Quebec city 's metropolitan area . PARTICIPANTS A final sample of 1110 patients among 1878 out patients invited to participate included 219 ( 19.7 % ) who tested positive for GAD . MAIN OUTCOME MEASURES Self-reported worry and anxiety ( based on DSM-IV criteria for GAD ) , self-perceived health problems , health care use and health care-seeking behaviour , insomnia , and symptoms of depression . RESULTS Participants who tested positive on a screening test for GAD reported more annual medical visits ( 5.3 versus 3.4 ) than other patients . Those who reported at least five annual medical visits were nearly four times more likely to have positive results for GAD . Women were 1.6 times more likely to have positive results than men were . Patients who tested positive reported insomnia-type sleep disturbances , depressive symptoms , fatigue , and gastric problems significantly more often than others . Forty-two percent had consulted a family physician in the past year with a complaint of anxiety . Eighty percent of patients who tested positive reported they believed they had an anxiety problem , and this belief predicted positive test results ( odds ratio = 20.3 ) . Yet most reported not having sought other types of medical or psychological care specifically for anxiety in the past year . CONCLUSION Some patients in this sample with symptoms of GAD mainly seek primary care for their symptoms . Questions about excessive worrying and anxiety , as part of routine examination , can increase recognition of GAD INTRODUCTION Tiredness is a common presentation in general practice for which pathology tests are commonly ordered . Our aim was to study their utilisation for tiredness . METHODS We examined an integrated data base which contains the medical records for 58,139 patients and their 696,518 associated general practitioner encounters . Three hundred and forty-two patients and their 1652 associated encounters were r and omly selected out of 12,291 patients and their 26,748 associated encounters that had mentioned tiredness ( or a synonym ) . RESULTS One hundred and eighty-one patients ( 53 % ) had at least one pathology test ordered at any time in their episode of care . Patients over 60 years of age , patients who consulted their GP more than once and patients without comorbidity were more likely to have a pathology test ordered . Only 12 patients ( 3 % ) had a significant clinical diagnosis based on an abnormal pathology test . CONCLUSION Pathology testing for patients presenting with tiredness is high . Most tests do not yield a significant clinical diagnosis OBJECTIVE --To describe the characteristics of patients attending their general practitioners and complaining of fatigue or being " tired all the time . " DESIGN -- Prospect i ve study of cohort aged 16 years and older with follow up at two weeks and by question naires at two and six months . SUBJECTS--220 patients ( 164 women ) with mean age 43 years and an age-sex matched comparison group . SETTING S -- Doctors and patients in four practice s in Lancashire , Mid Glamorgan , Suffolk , and Surrey . MAIN OUTCOME MEASURES --General clinical data , results from st and ard group of laboratory tests , fatigue question naire , and 12 item general health question naire . RESULTS --Over twice as many patients with fatigue had high scores on the health question naire compared with the comparison group ( 156 ( 75 % ) v 69 ( 34 % ) ) . Results of laboratory tests were abnormal and contributed to the diagnosis in 19 patients . 59 out of 102 patients who responded had high fatigue scores six months later . Patients with persistent fatigue were more likely to have a history of anxiety or depression and to have had fatigue for more than three months on entry to the study . CONCLUSIONS --Women are particularly at risk of fatigue . The outcome is better if patients have had symptoms for three months or less or there is no history of emotional illness BACKGROUND Unexplained fatigue is frequently encountered in general practice . Because of the low prior probability of underlying somatic pathology , the positive predictive value of abnormal ( blood ) test results is limited in such patients . AIM The study objectives were to investigate the relationship between established diagnoses and the occurrence of abnormal blood test results among patients with unexplained fatigue ; to survey the effects of the postponement of test ordering on this relationship ; and to explore consultation-related determinants of abnormal test results . DESIGN OF STUDY Cluster r and omised trial . SETTING General practice s of 91 GPs in the Netherl and s. METHOD GPs were r and omised to immediate or postponed blood-test ordering .  Patients with new unexplained fatigue were included . Limited and exp and ed sets of blood tests were ordered either immediately or after 4 weeks . Diagnoses during the 1-year follow-up period were extracted from medical records . Two-by-two tables were generated . To establish independent determinants of abnormal test results , a multivariate logistic regression model was used . RESULTS Data of 325 patients were analysed ( 71 % women ; mean age 41 years ) . Eight per cent of patients had a somatic illness that was detectable by blood-test ordering . The number of false-positive test results increased in particular in the exp and ed test set . Patients rarely re-consulted after 4 weeks . Test postponement did not affect the distribution of patients over the two-by-two tables . No independent consultation-related determinants of abnormal test results were found . CONCLUSION Results support restricting the number of tests ordered because of the increased risk of false-positive test results from exp and ed test sets . Although the number of re-consulting patients was small , the data do not refute the advice to postpone blood-test ordering for medical reasons in patients with unexplained fatigue in general practice To determine the psychiatric morbidity of patients complaining of chronic fatigue , we undertook a prospect i ve evaluation of 100 adults ( 65 women and 35 men ; mean age , 41 years ; and mean duration of chronic fatigue , 13 years ) . The study was conducted in an internal medicine outpatient clinic . In addition to a comprehensive medical evaluation , the patients were administered the 260-item Diagnostic Interview Schedule  , a highly structured instrument that enabled the physician-interviewer to make accurate psychiatric diagnoses . A thorough follow-up examination was given an average of 8.4 months later . Sixty-six patients had one or more psychiatric disorders that were considered a major cause of their chronic fatigue ( mood disorder , 47 patients ; somatization disorder , 15 patients ; and anxiety disorder , nine patients ) . Five patients had medical conditions that were considered a major cause of their fatigue . The complaint of chronic fatigue remained unexplained in 31 patients . In this prospect i ve study , two thirds of cases of chronic fatigue appeared to be caused by psychiatric disorders . A thorough evaluation of the mental health of patients complaining of chronic fatigue could therefore provide pharmacologic and psychotherapeutic approaches and avoid unnecessary and costly medical investigations and therapies BACKGROUND Early diagnosis of cancer is an important challenge in general practice . Symptoms are the most common starting points . OBJECTIVE To assess the association between symptoms presented and subsequent cancer . DESIGN A cohort study of all patients seen consecutively by GPs . Prospect i ve recording of cancer diagnosis , new cancer or new recurrence . SETTING Two hundred and eighty-three general practice surgeries and 10 working days . METHOD During patient consultations , GPs registered seven focal symptoms and three general symptoms , commonly considered as warning signs of cancer ( WSC ) . Follow-up 6 - 11 months later with registration of any subsequent diagnosis of cancer was done . RESULTS Of 51 073 patients , 6321 ( 12.4 % ) had recordings of 7704 WSC . During a median follow-up period of 8 months , 263 patients were diagnosed with cancer and 59 of them with recurrence of a previously diagnosed cancer . Of the cancer patients , 106 ( 40 % ) had presented one or more WSC during a preceding consultation . Examined symptoms had likelihood ratios for cancer from 1.5 to 8.2 and positive predictive values ( PPVs ) from 0.8 % to 3.8 % . Limited to older age groups , PPVs were a little higher . General symptoms were rarely associated with cancer unless a focal symptom had been recorded as well . Multiple symptoms increased the probability of cancer . CONCLUSION 12.4 % of GP patients presented with WSC  .  A general symptom may have cancer diagnostic value , but usually , only when it occurs along with a focal symptom . PPV of any single symptom is low , and decisions about referral require additional information Background : Little is known about the distribution of diagnoses that account for fatigue in patients in primary care . We evaluated the diagnoses established within 1 year after presentation with fatigue in primary care that were possibly associated with the fatigue . Methods : We conducted a prospect i ve observational cohort study with 1-year follow-up . We included adult patients who presented with a new episode of fatigue between June 2004 and January 2006 . We extracted data on diagnoses during the follow-up period from the patients ’ medical records as well as data on pre-existing chronic diseases . Results : Of the 571 patients for whom diagnostic data were available , 268 ( 46.9 % ) had received one or more diagnoses that could be associated with fatigue . The diagnoses were diverse and mostly included symptom diagnoses , with main categories being musculoskeletal ( 19.4 % ) and psychological problems ( 16.5 % ) . Clear somatic pathology was diagnosed in 47 ( 8.2 % ) of the patients . Most diagnoses were not made during the consultation when fatigue was presented . Interpretation : Only a minority of patients were diagnosed with serious pathology . Half of the patients did not receive any diagnosis that could explain their fatigue . Nevertheless , because of the wide range of conditions and symptoms that may explain or co-occur with the fatigue , fatigue is a complex problem that deserves attention not only as a symptom of underlying specific disease BACKGROUND Chronic fatigue syndrome ( CFS ) has been defined , but many more patients consult in primary care with chronic fatigue that does not meet the criteria for CFS . General practitioners ( GPs ) do not generally use the CFS diagnosis , and have some doubt about the validity of CFS as an illness . AIM To describe the proportion of patients consulting their GP for fatigue that met the criteria for CFS , and to describe the social , psychological , and physical differences between patients with CFS and those with non-CFS chronic fatigue in primary care . DESIGN OF STUDY Baseline data from a trial of complex interventions for fatigue in primary care . SETTING Twenty-two general practice s located in London and the South Thames region of the United Kingdom recruited patients to the study between 1999 and 2001 . METHOD One hundred and forty-one patients who presented to their GP with unexplained fatigue lasting six months or more as a main symptom were recruited , and the Centers for Disease Control ( CDC ) case definition was applied to classify CFS . RESULTS Approximately two-thirds ( 69 % ) of patients had chronic fatigue  and not CFS . The duration of fatigue ( 32 months ) and perceived control over fatigue were similar between groups ; however , fatigue , functioning , associated symptoms , and psychological distress were more severe in the patients in the CFS group , who also consulted their GP significantly more frequently , were twice as likely to be depressed , and more than twice as likely to be unemployed . About half ( CFS = 50 % ; chronic fatigue = 55 % ) in each group attributed their fatigue to mainly psychological causes . CONCLUSIONS In primary care , CFS is a more severe illness than chronic fatigue , but non-CFS chronic fatigue is associated with significant fatigue and is reported at least twice as often . That half of patients , irrespective of CFS status , attribute their fatigue to psychological causes , more than is observed in secondary care , indicates an openness to the psychological therapies provided in that setting . More evidence on the natural history of chronic fatigue and CFS in primary care is required , as are trials of complex interventions . The results may help determine the usefulness of differentiating between chronic fatigue and CFS BACKGROUND The symptom iceberg describes the phenomenon that most symptoms are managed in the community without people seeking professional health care . The size of the iceberg for many symptoms is unknown , as is their association with personal characteristics , including history of a chronic disease . AIM To ascertain the size of the symptom iceberg in the UK . DESIGN OF STUDY A UK-wide community-based postal survey . SETTING Urban and rural communities across the UK . METHOD A postal survey was sent to an age- and sex-stratified r and om sample of 2474 adults , aged 18 - 60 years , drawn from 20 practice s around the UK . Questions were aim ed at investigating adults ' experiences of 25 different symptoms in the previous 2 weeks . RESULTS The number of symptoms experienced by one individual in the previous 2 weeks ranged from 0 to 22 ( mean 3.66 ) . Of the symptoms examined , the three most common were : feeling tired/run down ; headaches ; and joint pain . Univariate analysis found symptom prevalence to be significantly associated with a wide range of participant characteristics . However , after 
    Output:
    