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: In clinical measurement comparison of a new measurement technique with an established one is often needed to see whether they agree sufficiently for the new to replace the old . Such investigations are often analysed inappropriately , notably by using correlation coefficients . The use of correlation is misleading . An alternative approach , based on graphical techniques and simple calculations , is described , together with the relation between this analysis and the assessment of repeatability Sleep-disordered breathing is a common disorder with a range of harmful sequelae . Obesity is a strong causal factor for sleep-disordered breathing , and because of the ongoing obesity epidemic , previous estimates of sleep-disordered breathing prevalence require updating . We estimated the prevalence of sleep-disordered breathing in the United States for the periods of 1988 - 1994 and 2007 - 2010 using data from the Wisconsin Sleep Cohort Study , an ongoing community-based study that was established in 1988 with participants r and omly selected from an employed population of Wisconsin adults . A total of 1,520 participants who were 30 - 70 years of age had baseline polysomnography studies to assess the presence of sleep-disordered breathing . Participants were invited for repeat studies at 4-year intervals . The prevalence of sleep-disordered breathing was modeled as a function of age , sex , and body mass index , and estimates were extrapolated to US body mass index distributions estimated using data from the National Health and Nutrition Examination Survey . The current prevalence estimates of moderate to severe sleep-disordered breathing ( apnea-hypopnea index , measured as events/hour , ≥15 ) are 10 % ( 95 % confidence interval ( CI ) : 7 , 12 ) among 30 - 49-year-old men ; 17 % ( 95 % CI : 15 , 21 ) among 50 - 70-year-old men ; 3 % ( 95 % CI : 2 , 4 ) among 30 - 49-year-old women ; and 9 % ( 95 % CI : 7 , 11 ) among 50 - 70 year-old women . These estimated prevalence rates represent substantial increases over the last 2 decades ( relative increases of between 14 % and 55 % depending on the subgroup ) STUDY OBJECTIVES Home-based diagnosis of obstructive sleep apnea ( OSA ) with portable monitoring ( PM ) is increasingly utilized , but remains understudied in underserved and minority population s. We tested the feasibility of home PM in an urban population at risk for OSA compared to in-laboratory polysomnography ( PSG ) and examined patient preference with respect to home PM versus PSG . METHODS R and omized crossover study of home PM ( WatchPAT200 ) and in-laboratory simultaneous PSG and PM in 75 urban African Americans with high pre-test probability of OSA , identified with the Berlin question naire . RESULTS Fifty-seven of 75 participants were women , average age 45 ± 11 years ( mean ± SD ) , 35 % with ≤ high school education , and 76 % with annual household income < $ 50,000 . Technical failure rates were 5.3 % for home vs. 3.1 % for in-laboratory PM . There was good agreement between apnea hypopnea index on PSG ; AHIPSG and AHI on home PM ( mean ± 2 SD of the differences = 0.64 ± 46.5 and intraclass correlation coefficient ; ICC = 0.73 ) . The areas under the curve for the receiver-operator characteristic curves for home PM were 0.90 for AHIPSG ≥ 5 , 0.95 for AHIPSG ≥ 10 , and 0.92 for AHIPSG ≥ 15 . 62/75 ( 82 % ) participants preferred home over in-laboratory testing . CONCLUSIONS Home PM for diagnosis of OSA in a high risk urban population is feasible , accurate , and preferred by patients . As home PM may improve access to care , the cost-effectiveness of this diagnostic strategy for OSA should be examined in underserved urban and rural population s. CLINICAL TRIALS REGISTRATION Clinical Trials.gov , identifier : NCT01997723 Obstructive sleep apnoea is a highly prevalent but under-diagnosed disorder . The gold st and ard for diagnosis of obstructive sleep apnoea is inpatient polysomnography . This is re source intensive and inconvenient for the patient , and the development of ambulatory diagnostic modalities has been identified as a key research priority . SleepMinder ( BiancaMed , NovaUCD , Irel and ) is a novel , non-contact , bedside sensor , which uses radio-waves to measure respiration and movement . Previous studies have shown it to be effective in measuring sleep and respiration . We sought to assess its utility in the diagnosis of obstructive sleep apnoea . SleepMinder and polysomnographic assessment of sleep-disordered breathing  were performed simultaneously on consecutive subjects recruited prospect ively from our sleep clinic . We assessed the diagnostic accuracy of SleepMinder in identifying  obstructive sleep apnoea  , and how SleepMinder assessment of the apnoea-hypopnoea index correlated with polysomnography .  Seventy-four subjects were recruited . The apnoea-hypopnoea index as measured by SleepMinder correlated strongly with polysomnographic measurement ( r = 0.90 ; P ≤ 0.0001 ) . When a diagnostic threshold of moderate-severe ( apnoea-hypopnoea index ≥15 events h(-1 ) ) obstructive sleep apnoea was used , SleepMinder displayed a sensitivity of 90 % , a specificity of 92 % and an accuracy of 91 % in the diagnosis of sleep-disordered breathing . The area under the curve for the receiver operator characteristic was 0.97 . SleepMinder  correctly classified obstructive sleep apnoea severity in the majority of cases , with only one case different from equivalent polysomnography by more than one diagnostic class . We conclude that in an unselected clinical population undergoing investigation for suspected obstructive sleep apnoea , SleepMinder measurement of sleep-disordered breathing correlates significantly with polysomnography Aim Polysomnography ( PSG ) is the current st and ard for diagnosing sleep apnea syndrome ( SAS ) . A reliable test would be useful to reduce the considerable re sources required for PSG . Methods We developed a new mathematical analysis , which quantifies amplitude variations of pulse oximetry ( SpO2 ) and heart rate ( HR ) throughout the night , allowing measurement of the total time in which ΔSpO2 > 4 % and presented as a new oximetric index ventilatory hypoxemic index ( VHI ) . VHI was compared prospect ively with st and ard PSG parameters apnea – hypopnea index ( AHI ) and oxygen desaturation index ( ODI )  in 106 patients ( aged , 57 ± 14 years ; BMI , 29 ± 5 kg/m2 ) suspected of having SAS . The criterion for diagnosis of SAS was AHI > 15/h of sleep during PSG . The relationship between ΔSpO2 and ΔΗR was also investigated . Results We observed a significant correlation between the AHI and VHI ( R = 0.87 , p < 0.0001 ) . Using VHI > 15 as the criterion for SpO2 , oximetry had a sensitivity of 81 % , specificity of 98 % , positive predictive value ( PPV ) of 98 % , and negative predictive value ( NPV ) of 84 % as a screening test for SAS . We also observed a clear linear relationship between ΔSpO2 and ΔΗR , and concomitant use of VHI and the ΔSpO2/ΔHR slope improved the NPV to 90 % . Conclusions The present findings from wavelet-aggregate processing of oximeter data and the relationship between ΔSpO2 and ΔΗR show promise as a useful summary prediction of screening SAS OBJECTIVE Laboratory-based polysomnography ( PSG ) is the gold st and ard for diagnosing obstructive sleep apnea-hypopnea syndrome ( OSAHS ) , but it is expensive and requires overnight hospitalization . Recently , a sheet-shaped breath detection monitor , the SD-101 , has been developed , and several reports have so far demonstrated the screening accuracy of this device . The aim of this study was to assess the accuracy and the uncertainty of this device . METHODS A total of 101 suspected OSAHS patients underwent simultaneous examinations with PSG and the SD-101 . RESULTS There was a statistically significant relationship between the respiratory disturbance index ( RDI ) by the SD-101 and the apnea-hypopnea index ( AHI ) by PSG . At an RDI cutoff of 14 episodes per hour , the sensitivity and specificity to detect an AHI ≥20 episodes per hour were 90.2 % and 90.0 % , respectively . To reduce the influence of sleep efficiency , the time in bed ( TIB ) obtained from PSG , instead of the total seep time ( TST ) , was used to calculate the AHI from the PSG data . There was also a statistically significant relationship between the RDI and AHI for the TIB . Moreover , it was suggested that arousal index and TIB were likely associated with false-negative and /or false-positive results . CONCLUSION Although the present study demonstrated a close relationship between the RDI and the AHI , use of the SD-101 to examine symptomatic OSAHS patients should be performed with a full underst and ing of its incapability to detect the sleep state , including arousal reaction and the existence of false respiratory events caused by body movements RATIONALE The most common single channel devices used for obstructive sleep apnea ( OSA ) screening are nasal airflow and oximetry . No studies have directly compared their role in diagnosing OSA at home . STUDY OBJECTIVES To prospect ively compare the diagnostic utility of home-based nasal airflow and oximetry to attended polysomnography ( PSG ) and to assess the diagnostic value of adding oximetry to nasal airflow for OSA . DESIGN Cross-sectional study . SETTING Laboratory and home . PARTICIPANTS Sleep clinic patients with suspected OSA . INTERVENTIONS All patients had laboratory PSG and 2 sets of 3 consecutive nights on each device ; nasal airflow ( Flow Wizard , DiagnoselT , Australia ) and oximetry ( Radical Set , Masimo , USA ) at home in r and om order . RESULTS Ninety-eight of the 105 patients enrolled completed home monitoring . The accuracy of nasal airflow respiratory disturbance index ( NF RDI ) was not different from oximetry ( ODI 3 % ) for diagnosing OSA ( area under the ROC curve ( AUC ) difference , 0.04 ; 95 % CI of difference -0.05 to 0.12 ; P = 0.43 ) over 3 nights of at-home recording . The accuracy of NF RDI was higher after 3 nights compared to one night ( AUC difference , 0.05 ; 95 % CI of difference , 0.01 to 0.08 ; P = 0.04 ) . Addition of oximetry to nasal airflow did not increase the accuracy for predicting OSA compared to nasal airflow alone ( P > 0.1 ) . CONCLUSIONS Nasal flow and oximetry have equivalent accuracy for diagnosing OSA in the home setting . Choice of device for home screening of sleep apnea may depend on logistical and service delivery issues OBJECTIVES Increasing awareness of the high prevalence of obstructive sleep apnea ( OSA ) and its impact on health in conjunction with high cost , inconvenience , and short supply of in-lab polysomnography ( PSG ) has led to the development of more convenient , affordable , and accessible diagnostic devices . We evaluated the reliability and accuracy of a single-channel ( finger pulse-oximetry ) photoplethysmography (PPG)-based device for detection of OSA ( Morpheus Ox ) . METHODS Among a cohort of 73 patients referred for in-laboratory evaluation of OSA , 65 were simultaneously monitored with the PPG based device while undergoing PSG .  Among these , 19 had significant cardiopulmonary comorbidities . Using the PSG as the " gold st and ard , " the sensitivity , specificity , negative predictive value ( NPV ) , positive predictive value ( PPV ) , as well as the positive likelihood ratio ( + LR ) for an apnea hypopnea index (AHI)PSG > 5/h and AHIPSG > 15/h were calculated for the PPG . RESULTS Valid results were available for 65 subjects . Mean age : 52.1 ± 14.2 , Male : 52 % , and BMI : 36.3 ± 9.7 kg/m(2 ) . Positive correlation was found between PPG-derived and PSG-derived AHI ( r = 0.81 , p < 0.001 ) . For AHIPSG > 5/h , sensitivity was 80 % , specificity 86 % , PPV 93 % , NPV 68 % , and + LR was 5.9 . For AHIPSG > 15/h , sensitivity was 70 % , specificity 91 % , PPV 80 % , NPV 85 % , and + LR was 7.83 . The corresponding areas under the receiver operator curves were 0.91 and 0.9 . CONCLUSIONS PPG-derived data compare well with simultaneous in-lab PSG in the diagnosis of suspected OSA among patients with and without cardiopulmonary comorbidities . CITATION Romem A ; Romem A ; Koldobskiy D ; Scharf SM . Diagnosis of obstructive sleep apnea using pulse oximeter derived photoplethysmographic signals BACKGROUND Sleep-disordered 
    Output:
    
agent
***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: In clinical measurement comparison of a new measurement technique with an established one is often needed to see whether they agree sufficiently for the new to replace the old . Such investigations are often analysed inappropriately , notably by using correlation coefficients . The use of correlation is misleading . An alternative approach , based on graphical techniques and simple calculations , is described , together with the relation between this analysis and the assessment of repeatability Sleep-disordered breathing is a common disorder with a range of harmful sequelae . Obesity is a strong causal factor for sleep-disordered breathing , and because of the ongoing obesity epidemic , previous estimates of sleep-disordered breathing prevalence require updating . We estimated the prevalence of sleep-disordered breathing in the United States for the periods of 1988 - 1994 and 2007 - 2010 using data from the Wisconsin Sleep Cohort Study , an ongoing community-based study that was established in 1988 with participants r and omly selected from an employed population of Wisconsin adults . A total of 1,520 participants who were 30 - 70 years of age had baseline polysomnography studies to assess the presence of sleep-disordered breathing . Participants were invited for repeat studies at 4-year intervals . The prevalence of sleep-disordered breathing was modeled as a function of age , sex , and body mass index , and estimates were extrapolated to US body mass index distributions estimated using data from the National Health and Nutrition Examination Survey . The current prevalence estimates of moderate to severe sleep-disordered breathing ( apnea-hypopnea index , measured as events/hour , ≥15 ) are 10 % ( 95 % confidence interval ( CI ) : 7 , 12 ) among 30 - 49-year-old men ; 17 % ( 95 % CI : 15 , 21 ) among 50 - 70-year-old men ; 3 % ( 95 % CI : 2 , 4 ) among 30 - 49-year-old women ; and 9 % ( 95 % CI : 7 , 11 ) among 50 - 70 year-old women . These estimated prevalence rates represent substantial increases over the last 2 decades ( relative increases of between 14 % and 55 % depending on the subgroup ) STUDY OBJECTIVES Home-based diagnosis of obstructive sleep apnea ( OSA ) with portable monitoring ( PM ) is increasingly utilized , but remains understudied in underserved and minority population s. We tested the feasibility of home PM in an urban population at risk for OSA compared to in-laboratory polysomnography ( PSG ) and examined patient preference with respect to home PM versus PSG . METHODS R and omized crossover study of home PM ( WatchPAT200 ) and in-laboratory simultaneous PSG and PM in 75 urban African Americans with high pre-test probability of OSA , identified with the Berlin question naire . RESULTS Fifty-seven of 75 participants were women , average age 45 ± 11 years ( mean ± SD ) , 35 % with ≤ high school education , and 76 % with annual household income < $ 50,000 . Technical failure rates were 5.3 % for home vs. 3.1 % for in-laboratory PM . There was good agreement between apnea hypopnea index on PSG ; AHIPSG and AHI on home PM ( mean ± 2 SD of the differences = 0.64 ± 46.5 and intraclass correlation coefficient ; ICC = 0.73 ) . The areas under the curve for the receiver-operator characteristic curves for home PM were 0.90 for AHIPSG ≥ 5 , 0.95 for AHIPSG ≥ 10 , and 0.92 for AHIPSG ≥ 15 . 62/75 ( 82 % ) participants preferred home over in-laboratory testing . CONCLUSIONS Home PM for diagnosis of OSA in a high risk urban population is feasible , accurate , and preferred by patients . As home PM may improve access to care , the cost-effectiveness of this diagnostic strategy for OSA should be examined in underserved urban and rural population s. CLINICAL TRIALS REGISTRATION Clinical Trials.gov , identifier : NCT01997723 Obstructive sleep apnoea is a highly prevalent but under-diagnosed disorder . The gold st and ard for diagnosis of obstructive sleep apnoea is inpatient polysomnography . This is re source intensive and inconvenient for the patient , and the development of ambulatory diagnostic modalities has been identified as a key research priority . SleepMinder ( BiancaMed , NovaUCD , Irel and ) is a novel , non-contact , bedside sensor , which uses radio-waves to measure respiration and movement . Previous studies have shown it to be effective in measuring sleep and respiration . We sought to assess its utility in the diagnosis of obstructive sleep apnoea . SleepMinder and polysomnographic assessment of sleep-disordered breathing  were performed simultaneously on consecutive subjects recruited prospect ively from our sleep clinic . We assessed the diagnostic accuracy of SleepMinder in identifying  obstructive sleep apnoea  , and how SleepMinder assessment of the apnoea-hypopnoea index correlated with polysomnography .  Seventy-four subjects were recruited . The apnoea-hypopnoea index as measured by SleepMinder correlated strongly with polysomnographic measurement ( r = 0.90 ; P ≤ 0.0001 ) . When a diagnostic threshold of moderate-severe ( apnoea-hypopnoea index ≥15 events h(-1 ) ) obstructive sleep apnoea was used , SleepMinder displayed a sensitivity of 90 % , a specificity of 92 % and an accuracy of 91 % in the diagnosis of sleep-disordered breathing . The area under the curve for the receiver operator characteristic was 0.97 . SleepMinder  correctly classified obstructive sleep apnoea severity in the majority of cases , with only one case different from equivalent polysomnography by more than one diagnostic class . We conclude that in an unselected clinical population undergoing investigation for suspected obstructive sleep apnoea , SleepMinder measurement of sleep-disordered breathing correlates significantly with polysomnography Aim Polysomnography ( PSG ) is the current st and ard for diagnosing sleep apnea syndrome ( SAS ) . A reliable test would be useful to reduce the considerable re sources required for PSG . Methods We developed a new mathematical analysis , which quantifies amplitude variations of pulse oximetry ( SpO2 ) and heart rate ( HR ) throughout the night , allowing measurement of the total time in which ΔSpO2 > 4 % and presented as a new oximetric index ventilatory hypoxemic index ( VHI ) . VHI was compared prospect ively with st and ard PSG parameters apnea – hypopnea index ( AHI ) and oxygen desaturation index ( ODI )  in 106 patients ( aged , 57 ± 14 years ; BMI , 29 ± 5 kg/m2 ) suspected of having SAS . The criterion for diagnosis of SAS was AHI > 15/h of sleep during PSG . The relationship between ΔSpO2 and ΔΗR was also investigated . Results We observed a significant correlation between the AHI and VHI ( R = 0.87 , p < 0.0001 ) . Using VHI > 15 as the criterion for SpO2 , oximetry had a sensitivity of 81 % , specificity of 98 % , positive predictive value ( PPV ) of 98 % , and negative predictive value ( NPV ) of 84 % as a screening test for SAS . We also observed a clear linear relationship between ΔSpO2 and ΔΗR , and concomitant use of VHI and the ΔSpO2/ΔHR slope improved the NPV to 90 % . Conclusions The present findings from wavelet-aggregate processing of oximeter data and the relationship between ΔSpO2 and ΔΗR show promise as a useful summary prediction of screening SAS OBJECTIVE Laboratory-based polysomnography ( PSG ) is the gold st and ard for diagnosing obstructive sleep apnea-hypopnea syndrome ( OSAHS ) , but it is expensive and requires overnight hospitalization . Recently , a sheet-shaped breath detection monitor , the SD-101 , has been developed , and several reports have so far demonstrated the screening accuracy of this device . The aim of this study was to assess the accuracy and the uncertainty of this device . METHODS A total of 101 suspected OSAHS patients underwent simultaneous examinations with PSG and the SD-101 . RESULTS There was a statistically significant relationship between the respiratory disturbance index ( RDI ) by the SD-101 and the apnea-hypopnea index ( AHI ) by PSG . At an RDI cutoff of 14 episodes per hour , the sensitivity and specificity to detect an AHI ≥20 episodes per hour were 90.2 % and 90.0 % , respectively . To reduce the influence of sleep efficiency , the time in bed ( TIB ) obtained from PSG , instead of the total seep time ( TST ) , was used to calculate the AHI from the PSG data . There was also a statistically significant relationship between the RDI and AHI for the TIB . Moreover , it was suggested that arousal index and TIB were likely associated with false-negative and /or false-positive results . CONCLUSION Although the present study demonstrated a close relationship between the RDI and the AHI , use of the SD-101 to examine symptomatic OSAHS patients should be performed with a full underst and ing of its incapability to detect the sleep state , including arousal reaction and the existence of false respiratory events caused by body movements RATIONALE The most common single channel devices used for obstructive sleep apnea ( OSA ) screening are nasal airflow and oximetry . No studies have directly compared their role in diagnosing OSA at home . STUDY OBJECTIVES To prospect ively compare the diagnostic utility of home-based nasal airflow and oximetry to attended polysomnography ( PSG ) and to assess the diagnostic value of adding oximetry to nasal airflow for OSA . DESIGN Cross-sectional study . SETTING Laboratory and home . PARTICIPANTS Sleep clinic patients with suspected OSA . INTERVENTIONS All patients had laboratory PSG and 2 sets of 3 consecutive nights on each device ; nasal airflow ( Flow Wizard , DiagnoselT , Australia ) and oximetry ( Radical Set , Masimo , USA ) at home in r and om order . RESULTS Ninety-eight of the 105 patients enrolled completed home monitoring . The accuracy of nasal airflow respiratory disturbance index ( NF RDI ) was not different from oximetry ( ODI 3 % ) for diagnosing OSA ( area under the ROC curve ( AUC ) difference , 0.04 ; 95 % CI of difference -0.05 to 0.12 ; P = 0.43 ) over 3 nights of at-home recording . The accuracy of NF RDI was higher after 3 nights compared to one night ( AUC difference , 0.05 ; 95 % CI of difference , 0.01 to 0.08 ; P = 0.04 ) . Addition of oximetry to nasal airflow did not increase the accuracy for predicting OSA compared to nasal airflow alone ( P > 0.1 ) . CONCLUSIONS Nasal flow and oximetry have equivalent accuracy for diagnosing OSA in the home setting . Choice of device for home screening of sleep apnea may depend on logistical and service delivery issues OBJECTIVES Increasing awareness of the high prevalence of obstructive sleep apnea ( OSA ) and its impact on health in conjunction with high cost , inconvenience , and short supply of in-lab polysomnography ( PSG ) has led to the development of more convenient , affordable , and accessible diagnostic devices . We evaluated the reliability and accuracy of a single-channel ( finger pulse-oximetry ) photoplethysmography (PPG)-based device for detection of OSA ( Morpheus Ox ) . METHODS Among a cohort of 73 patients referred for in-laboratory evaluation of OSA , 65 were simultaneously monitored with the PPG based device while undergoing PSG .  Among these , 19 had significant cardiopulmonary comorbidities . Using the PSG as the " gold st and ard , " the sensitivity , specificity , negative predictive value ( NPV ) , positive predictive value ( PPV ) , as well as the positive likelihood ratio ( + LR ) for an apnea hypopnea index (AHI)PSG > 5/h and AHIPSG > 15/h were calculated for the PPG . RESULTS Valid results were available for 65 subjects . Mean age : 52.1 ± 14.2 , Male : 52 % , and BMI : 36.3 ± 9.7 kg/m(2 ) . Positive correlation was found between PPG-derived and PSG-derived AHI ( r = 0.81 , p < 0.001 ) . For AHIPSG > 5/h , sensitivity was 80 % , specificity 86 % , PPV 93 % , NPV 68 % , and + LR was 5.9 . For AHIPSG > 15/h , sensitivity was 70 % , specificity 91 % , PPV 80 % , NPV 85 % , and + LR was 7.83 . The corresponding areas under the receiver operator curves were 0.91 and 0.9 . CONCLUSIONS PPG-derived data compare well with simultaneous in-lab PSG in the diagnosis of suspected OSA among patients with and without cardiopulmonary comorbidities . CITATION Romem A ; Romem A ; Koldobskiy D ; Scharf SM . Diagnosis of obstructive sleep apnea using pulse oximeter derived photoplethysmographic signals BACKGROUND Sleep-disordered 
    Output:
    