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: Study design : A prospect i ve study . Objectives : To evaluate the changes of functional abilities , incidences of complications and falls of patients with spinal cord injury ( SCI ) 6 months after discharge . Setting : A major tertiary referral hospital , Thail and . Methods : Forty-four patients with SCI completed the study . Their average age and post-injury time were 45.23±13.78 years and 51.52±47.87 months respectively .  Functional abilities of the subjects were measured by using the  Spinal Cord Independence Measure II ( SCIM II ) . Incidences of complications and falls were prospect ively assessed every month by using a question naire . Results : After 6 months , the SCIM II scores of subjects showed a slight decrease ( 58.60±21.22–58.37±22.06 scores ) . The significant decrement was illustrated in self-care and mobility scores of subjects with chronic motor incomplete SCI ( P<0.05 ) . Forty subjects experienced at least one medical complication ( range 1–5 times ) which 11 of them had to re-admit for 3–30 days . Twenty-four subjects sustained at least one fall in 6 months ( range 1–24 times ) which one subject had metatarsal bone fracture after fall . Conclusion : The functional ability of subjects with SCI , particularly those with chronic motor incomplete SCI , significantly decreased after discharge . The subjects also encountered a high risk of complications and falls that might associate with the decrement of functional ability . The findings confirmed important roles of community rehabilitation after discharge Elderly individuals with AD are more susceptible to falls , which might be associated with decrements in their executive functions and balance , among other things . We aim ed to analyze the effects of a program of dual task physical activity on falls , executive functions and balance of elderly individuals with AD . We studied 21 elderly with probable AD , allocated to two groups : the training group ( TG ) , with 10 elderly who participated in a program of dual task physical activity ; and the control group ( CG ) , with 11 elderly who were not engaged in regular practice of physical activity .  The  Clock Drawing Test ( CDT ) and the Frontal Assessment Battery ( FAB ) were used in the assessment of the executive functions , while the  Berg Balance Scale ( BBS ) and the Timed Up- and -Go (TUG)-test evaluated balance . The number of falls was obtained by means of a question naire . We observed a better performance of the TG as regards balance and executive functions . Moreover , the lower the number of steps in the TUG scale , the higher the scores in the CDT , and in the FAB . The practice of regular physical activity with dual task seems to have contributed to the maintenance and improvement of the motor and cognitive functions of the elderly with AD We conducted a retrospective case-control study of falls over a four year period on a 30 bed neurorehabilitation unit at the Burke Rehabilitation Hospital to characterize the nature of falls and identify factors associated with falling . The most common diagnoses treated on the unit were traumatic spinal cord injury , brain injury , and multiple sclerosis ; stroke patients are treated on another service . Falls represented 72 percent of all incident reports made to the Nursing Office during the study period . One hundred seventeen ( 117 ) falls occurred in 82 patients during a time when the unit census was 28,622 patient days , yielding a rate of 1,439 falls per 1,000 patient years . One hundred fourteen ( 114 ) patients admitted with no history of falling during the same period were selected r and omly for comparison . Most falls were associated with no injury ( n = 96 ) or minor injury ( n = 18 ) . The most significant injuries occurred in three cases with lacerations requiring sutures . Falls occurred with greatest frequency during the first and fourth quartiles of the hospital stay , during the evening and while bed transfers were being performed . No association between falling and patient age , sex , diagnosis , number of medications , use of sedating medications , presence of motor , visual or cognitive impairment or orthostatic hypotension was evident . An increased risk of falling was associated with physician orders for Posey restraints . The implication of these findings for falls prevention programs is discussed OBJECTIVE To identify measures of balance , gait , and strength that predict falls in women with multiple sclerosis ( MS ) . DESIGN This prospect i ve study followed participants for 1 year . SETTING University research laboratories . PARTICIPANTS A convenience sample of women with MS ( N=99 ) . INTERVENTIONS Not applicable . MAIN OUTCOME MEASURES Balance was assessed with the  limits of stability ( LOS ) test  and the  Sensory Organization Test .  Peak force , torque , and power of knee flexors and extensors as well as hip abductors and adductors were also measured . Temporal-spatial parameters of gait  were measured by an instrumented walkway system . For 1 year after baseline assessment s , the participants reported their falls . Participants were then classified based on the number of reported falls for use in logistic regression models to predict either people with at least 1 fall or people with at least 2 falls ( recurrent fallers ) . RESULTS A total of 159 falls were reported by 48 % of the participants .  Exp and ed Disability Status Scale scores , leaning forward to the LOS , and st and ing sway within a visually referenced surround significantly predicted people with at least 1 fall as well as recurrent fallers . Stance-phase asymmetries and base-of-support width during gait , as well as the force and power produced during leg extension or flexion additionally predicted recurrent fallers . The models ' overall predictive accuracy ranged from 69 % to 85 % . CONCLUSIONS This prospect i ve study confirmed the prevalence and multifactorial nature of falls in this MS sample . In addition to advancing disease status , impaired forward LOS and visually dependent sway ( as well as gait asymmetries and leg flexor-extensor weakness for recurrent fallers ) predict future falls in women with MS Objective : To investigate accidental falls and near fall incidents in people with multiple sclerosis with respect to clinical variables and the predictive values of four tests . Design : A longitudinal , multi-centred cohort study with prospect ively collected falls . Procedures : Self-reported incidents during the three months following a st and ardized test procedure . Subjects : Seventy-six people with multiple sclerosis and an Exp and ed Disability Status Scale score between 3.5 and 6.0 . Main outcome measures : Berg Balance Scale , Timed Up and Go cognitive , Four Square Step Test ( FSST ) and 12-item Multiple Sclerosis Walking Scale . Results : Forty-eight people ( 63 % ) registered 270 falls . Most falls occurred indoors during activities of daily life . We found a correlation of rs=0.57 between near falls and falls , and of rs = 0.82 between registered and retrospectively recalled falls . Fallers and non-fallers differed significantly regarding Exp and ed Disability Status Score ( odds ratio ( OR ) 1.99 , 95 % confidence interval ( CI ) 1.22 ; 3.40 ) , spasticity ( OR 1.14 , CI 1.02 ; 1.31 ) , proprioception ( OR 2.50 , CI 1.36 ; 5.12 ) and use of walking aids ( OR 2.27 , CI 1.23 ; 4.37 ) . Reported use of walking aids both indoors and outdoors increased the odds of falling fivefold while disturbed proprioception increased the odds 2.5—15.6 times depending on severity . The odds of falling were doubled for each degree of increased Exp and ed Disability Status Score and more than doubled for each degree of increased spasticity . The Berg Balance Scale , use of walking aids and Timed Up and Go cognitive best identified fallers ( 73—94 % ) and proprioception , Exp and ed Disability Status Score , 12-item Multiple Sclerosis Walking Scale and Four Square Step Test best identified non-fallers ( 75—93 % ) . Conclusions : In clinical practice , looking at the use of walking aids , investigating proprioception and spasticity , rating Exp and ed Disability Status Score and using Berg Balance Scale or Timed Up and Go cognitive all contribute when identifying fallers Background There is a lack of information concerning the relation between objective measures of gait and balance and fall history in persons with MS ( PwMS ) . This investigation assessed the relation between demographic , clinical , mobility and balance metrics and falls history in persons with multiple sclerosis ( MS ) . Methods 52 ambulatory persons with MS ( PwMS ) participated in the investigation . All persons provided demographic information including fall history over the last 12 months . Disease status was assessed with Exp and  ed Disability Status Scale ( EDSS ) . Walking speed , coordination , endurance and postural control were quantified with a multidimensional mobility battery . Results Over 51 % of the participants fell in the previous year with 79 % of these people being suffering recurrent falls . Overall , fallers were older , had a greater prevalence of assistive devices use , worse disability , decreased walking endurance , and greater postural sway velocity with eyes closed compared to non-fallers . Additionally , fallers had greater impairment in cerebellar , sensory , pyramidal , and bladder/bowel subscales of the EDSS . Conclusions The current observations suggest that PwMS who are older , more disabled , utilize an assistive device , have decreased walking coordination and endurance and have diminished balance have fallen in the previous year . This suggests that individuals who meet these criteria need to be carefully monitored for future falls . Future research is needed to determine a prospect i ve model of falls specific to PwMS . Additionally , the utility of interventions aim ed at reducing falls and fall risk in PwMS needs to be established BACKGROUND Cognition influences gait and balance in elderly people . Executive functions seem to play a key role in this mechanism . Previous studies used only a single test to probe executive functions , and outcome measures were restricted to gait variables . We extend this prior work by examining the association between two different executive functions and measures of both gait and balance , with and without two different cognitive dual tasks . METHODS This is a cross-sectional study with r and omly selected community-living elderly people . Executive functions were tested with the Trail Making Test Parts A and B and the Stroop Color Word Test ; memory with Cambridge Neuropsychological Test Automated Battery ( CANTAB ) subtests . Patients walked without and with two dual tasks ( subtracting serial sevens and animal naming ) . Main outcomes focused on gait ( velocity , stride length , and stride time variability ) , measured on an electronic walkway , and balance , measured as trunk movements during walking . Associations were assessed with multiple regression models . RESULTS One hundred elderly people , with a mean age 80.6 years ( range 75 - 93 years ) participated . Both dual tasks decreased gait velocity and increased variability and trunk sway . Executive functions were associated with only stride length variability and mediolateral trunk sway during performance of animal naming as the dual task . Memory was not associated with the gait and balance variables . CONCLUSIONS In community-living elderly people , executive functions are associated with gait and balance impairment during a challenging dual-task condition that also depends on executive integrity . Next steps will be to explore the value of executive functions in defining fall-risk profiles and in fall-prevention interventions for frail patients Abstract Background / Objective : To determine factors associated with falls among a sample of ambulatory individuals with incomplete spinal cord injury ( SCI ) . Study Design : Cross-sectional mail survey . Methods : A survey instrument of participant characteristics and fall-related variables was developed using relevant items from existing measures and was mailed to 221 individuals with incomplete SCI , who were identified from records of a large specialty hospital in the southeastern United States . Of the 221 prospect i ve participants , 119 completed the question naire ( 54 % ) . Multivariable logistic regression models were used to determine factors that were independently associated with having had a fall in the past year . Results : After adjusting for covariates , having fallen in the past year was significantly ( P < 0.05 ) associated with greater numbers of medical conditions ( odds ratio [ OR ] = 1.3 ; 95 % confidence interval [ Cl ] = 1.0 - 1.7 ) , having arthritis ( OR = 3.4 , 95 % Cl = 1.2 - 9.6 ) , experiencing dizziness ( OR = 5.6 , 95 % Cl = 1.1 - 27.7 ) , greater numbers of days with poor physical health ( OR = 1.1 ; 95 % Cl = 1.0 - 1.3 ) , and the restriction of community activities because of fear of falling ( OR = 1.5 , 95 % Cl = 1.1 - 2.1 ) . The multivariable models also showed that the odds of having fallen were significantly lower among those with better current perceived physical health ( OR = 0.5 ; 95 % Cl = 0.3 - 0.9 ) , those with better perceived health compared to a year ago ( OR = 0.4 ; 95 % Cl = 0.2 - 0.8 ) , individuals who exercised more frequently ( OR = 0.2 ; 95 % Cl = 0.1 - 0.7 ) , and those who used a walker ( OR = 0.3 ; 95 % CI = 0.1 - 0.9 ) . Conclusions : Results suggest that interventions that address  exercise frequency , walker use , and dizziness have promise for reducing falls for individuals with incomplete SCI OBJECTIVES ( 1 ) To determine the incidence of wheelchair falls and fall-related injuries in persons with spinal cord injury ( SCI ) living in the community . ( 2 ) To predict wheelchair-related falls and associated injuries from specific parameters including characteristics of the wheelchair user , wheelchair type and features , health care practice s , wheelchair activities , and physical environment . DESIGN This prospect i ve cohort study followed participants monthly over 1 year ; data were collected through surveys , interviews , performance testing , observation , and medical records . SETTING Three Veterans ' Administration hospitals . PARTICIPANTS Convenience sample 
    Output:
    
agent
Among the multiple risk factors studied , a reduced performance in balance and gait was consistently associated with falls , while the contribution of single physical and cognitive impairments was variable in different population s. Walking aids , wheelchair characteristics and environmental hazards are significant environmental risk factors .
Falling is a common problem among young patients affected by neurological disorders , although the risk of falling for a specific individual is difficult to predict and the risk of a severe fall-related injury has not yet been established .
IMPLICATION S FOR REHABILITATION Young patients with impaired gait and balance or medium to severe motor disability appear to be at increased risk of falling .
Patients who are relatively independent and still participating in challenging activities have an increased exposure to fall-risk .
Walking aids , wheelchair characteristics and environmental hazards are significant environmental risk factors .
***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: Study design : A prospect i ve study . Objectives : To evaluate the changes of functional abilities , incidences of complications and falls of patients with spinal cord injury ( SCI ) 6 months after discharge . Setting : A major tertiary referral hospital , Thail and . Methods : Forty-four patients with SCI completed the study . Their average age and post-injury time were 45.23±13.78 years and 51.52±47.87 months respectively .  Functional abilities of the subjects were measured by using the  Spinal Cord Independence Measure II ( SCIM II ) . Incidences of complications and falls were prospect ively assessed every month by using a question naire . Results : After 6 months , the SCIM II scores of subjects showed a slight decrease ( 58.60±21.22–58.37±22.06 scores ) . The significant decrement was illustrated in self-care and mobility scores of subjects with chronic motor incomplete SCI ( P<0.05 ) . Forty subjects experienced at least one medical complication ( range 1–5 times ) which 11 of them had to re-admit for 3–30 days . Twenty-four subjects sustained at least one fall in 6 months ( range 1–24 times ) which one subject had metatarsal bone fracture after fall . Conclusion : The functional ability of subjects with SCI , particularly those with chronic motor incomplete SCI , significantly decreased after discharge . The subjects also encountered a high risk of complications and falls that might associate with the decrement of functional ability . The findings confirmed important roles of community rehabilitation after discharge Elderly individuals with AD are more susceptible to falls , which might be associated with decrements in their executive functions and balance , among other things . We aim ed to analyze the effects of a program of dual task physical activity on falls , executive functions and balance of elderly individuals with AD . We studied 21 elderly with probable AD , allocated to two groups : the training group ( TG ) , with 10 elderly who participated in a program of dual task physical activity ; and the control group ( CG ) , with 11 elderly who were not engaged in regular practice of physical activity .  The  Clock Drawing Test ( CDT ) and the Frontal Assessment Battery ( FAB ) were used in the assessment of the executive functions , while the  Berg Balance Scale ( BBS ) and the Timed Up- and -Go (TUG)-test evaluated balance . The number of falls was obtained by means of a question naire . We observed a better performance of the TG as regards balance and executive functions . Moreover , the lower the number of steps in the TUG scale , the higher the scores in the CDT , and in the FAB . The practice of regular physical activity with dual task seems to have contributed to the maintenance and improvement of the motor and cognitive functions of the elderly with AD We conducted a retrospective case-control study of falls over a four year period on a 30 bed neurorehabilitation unit at the Burke Rehabilitation Hospital to characterize the nature of falls and identify factors associated with falling . The most common diagnoses treated on the unit were traumatic spinal cord injury , brain injury , and multiple sclerosis ; stroke patients are treated on another service . Falls represented 72 percent of all incident reports made to the Nursing Office during the study period . One hundred seventeen ( 117 ) falls occurred in 82 patients during a time when the unit census was 28,622 patient days , yielding a rate of 1,439 falls per 1,000 patient years . One hundred fourteen ( 114 ) patients admitted with no history of falling during the same period were selected r and omly for comparison . Most falls were associated with no injury ( n = 96 ) or minor injury ( n = 18 ) . The most significant injuries occurred in three cases with lacerations requiring sutures . Falls occurred with greatest frequency during the first and fourth quartiles of the hospital stay , during the evening and while bed transfers were being performed . No association between falling and patient age , sex , diagnosis , number of medications , use of sedating medications , presence of motor , visual or cognitive impairment or orthostatic hypotension was evident . An increased risk of falling was associated with physician orders for Posey restraints . The implication of these findings for falls prevention programs is discussed OBJECTIVE To identify measures of balance , gait , and strength that predict falls in women with multiple sclerosis ( MS ) . DESIGN This prospect i ve study followed participants for 1 year . SETTING University research laboratories . PARTICIPANTS A convenience sample of women with MS ( N=99 ) . INTERVENTIONS Not applicable . MAIN OUTCOME MEASURES Balance was assessed with the  limits of stability ( LOS ) test  and the  Sensory Organization Test .  Peak force , torque , and power of knee flexors and extensors as well as hip abductors and adductors were also measured . Temporal-spatial parameters of gait  were measured by an instrumented walkway system . For 1 year after baseline assessment s , the participants reported their falls . Participants were then classified based on the number of reported falls for use in logistic regression models to predict either people with at least 1 fall or people with at least 2 falls ( recurrent fallers ) . RESULTS A total of 159 falls were reported by 48 % of the participants .  Exp and ed Disability Status Scale scores , leaning forward to the LOS , and st and ing sway within a visually referenced surround significantly predicted people with at least 1 fall as well as recurrent fallers . Stance-phase asymmetries and base-of-support width during gait , as well as the force and power produced during leg extension or flexion additionally predicted recurrent fallers . The models ' overall predictive accuracy ranged from 69 % to 85 % . CONCLUSIONS This prospect i ve study confirmed the prevalence and multifactorial nature of falls in this MS sample . In addition to advancing disease status , impaired forward LOS and visually dependent sway ( as well as gait asymmetries and leg flexor-extensor weakness for recurrent fallers ) predict future falls in women with MS Objective : To investigate accidental falls and near fall incidents in people with multiple sclerosis with respect to clinical variables and the predictive values of four tests . Design : A longitudinal , multi-centred cohort study with prospect ively collected falls . Procedures : Self-reported incidents during the three months following a st and ardized test procedure . Subjects : Seventy-six people with multiple sclerosis and an Exp and ed Disability Status Scale score between 3.5 and 6.0 . Main outcome measures : Berg Balance Scale , Timed Up and Go cognitive , Four Square Step Test ( FSST ) and 12-item Multiple Sclerosis Walking Scale . Results : Forty-eight people ( 63 % ) registered 270 falls . Most falls occurred indoors during activities of daily life . We found a correlation of rs=0.57 between near falls and falls , and of rs = 0.82 between registered and retrospectively recalled falls . Fallers and non-fallers differed significantly regarding Exp and ed Disability Status Score ( odds ratio ( OR ) 1.99 , 95 % confidence interval ( CI ) 1.22 ; 3.40 ) , spasticity ( OR 1.14 , CI 1.02 ; 1.31 ) , proprioception ( OR 2.50 , CI 1.36 ; 5.12 ) and use of walking aids ( OR 2.27 , CI 1.23 ; 4.37 ) . Reported use of walking aids both indoors and outdoors increased the odds of falling fivefold while disturbed proprioception increased the odds 2.5—15.6 times depending on severity . The odds of falling were doubled for each degree of increased Exp and ed Disability Status Score and more than doubled for each degree of increased spasticity . The Berg Balance Scale , use of walking aids and Timed Up and Go cognitive best identified fallers ( 73—94 % ) and proprioception , Exp and ed Disability Status Score , 12-item Multiple Sclerosis Walking Scale and Four Square Step Test best identified non-fallers ( 75—93 % ) . Conclusions : In clinical practice , looking at the use of walking aids , investigating proprioception and spasticity , rating Exp and ed Disability Status Score and using Berg Balance Scale or Timed Up and Go cognitive all contribute when identifying fallers Background There is a lack of information concerning the relation between objective measures of gait and balance and fall history in persons with MS ( PwMS ) . This investigation assessed the relation between demographic , clinical , mobility and balance metrics and falls history in persons with multiple sclerosis ( MS ) . Methods 52 ambulatory persons with MS ( PwMS ) participated in the investigation . All persons provided demographic information including fall history over the last 12 months . Disease status was assessed with Exp and  ed Disability Status Scale ( EDSS ) . Walking speed , coordination , endurance and postural control were quantified with a multidimensional mobility battery . Results Over 51 % of the participants fell in the previous year with 79 % of these people being suffering recurrent falls . Overall , fallers were older , had a greater prevalence of assistive devices use , worse disability , decreased walking endurance , and greater postural sway velocity with eyes closed compared to non-fallers . Additionally , fallers had greater impairment in cerebellar , sensory , pyramidal , and bladder/bowel subscales of the EDSS . Conclusions The current observations suggest that PwMS who are older , more disabled , utilize an assistive device , have decreased walking coordination and endurance and have diminished balance have fallen in the previous year . This suggests that individuals who meet these criteria need to be carefully monitored for future falls . Future research is needed to determine a prospect i ve model of falls specific to PwMS . Additionally , the utility of interventions aim ed at reducing falls and fall risk in PwMS needs to be established BACKGROUND Cognition influences gait and balance in elderly people . Executive functions seem to play a key role in this mechanism . Previous studies used only a single test to probe executive functions , and outcome measures were restricted to gait variables . We extend this prior work by examining the association between two different executive functions and measures of both gait and balance , with and without two different cognitive dual tasks . METHODS This is a cross-sectional study with r and omly selected community-living elderly people . Executive functions were tested with the Trail Making Test Parts A and B and the Stroop Color Word Test ; memory with Cambridge Neuropsychological Test Automated Battery ( CANTAB ) subtests . Patients walked without and with two dual tasks ( subtracting serial sevens and animal naming ) . Main outcomes focused on gait ( velocity , stride length , and stride time variability ) , measured on an electronic walkway , and balance , measured as trunk movements during walking . Associations were assessed with multiple regression models . RESULTS One hundred elderly people , with a mean age 80.6 years ( range 75 - 93 years ) participated . Both dual tasks decreased gait velocity and increased variability and trunk sway . Executive functions were associated with only stride length variability and mediolateral trunk sway during performance of animal naming as the dual task . Memory was not associated with the gait and balance variables . CONCLUSIONS In community-living elderly people , executive functions are associated with gait and balance impairment during a challenging dual-task condition that also depends on executive integrity . Next steps will be to explore the value of executive functions in defining fall-risk profiles and in fall-prevention interventions for frail patients Abstract Background / Objective : To determine factors associated with falls among a sample of ambulatory individuals with incomplete spinal cord injury ( SCI ) . Study Design : Cross-sectional mail survey . Methods : A survey instrument of participant characteristics and fall-related variables was developed using relevant items from existing measures and was mailed to 221 individuals with incomplete SCI , who were identified from records of a large specialty hospital in the southeastern United States . Of the 221 prospect i ve participants , 119 completed the question naire ( 54 % ) . Multivariable logistic regression models were used to determine factors that were independently associated with having had a fall in the past year . Results : After adjusting for covariates , having fallen in the past year was significantly ( P < 0.05 ) associated with greater numbers of medical conditions ( odds ratio [ OR ] = 1.3 ; 95 % confidence interval [ Cl ] = 1.0 - 1.7 ) , having arthritis ( OR = 3.4 , 95 % Cl = 1.2 - 9.6 ) , experiencing dizziness ( OR = 5.6 , 95 % Cl = 1.1 - 27.7 ) , greater numbers of days with poor physical health ( OR = 1.1 ; 95 % Cl = 1.0 - 1.3 ) , and the restriction of community activities because of fear of falling ( OR = 1.5 , 95 % Cl = 1.1 - 2.1 ) . The multivariable models also showed that the odds of having fallen were significantly lower among those with better current perceived physical health ( OR = 0.5 ; 95 % Cl = 0.3 - 0.9 ) , those with better perceived health compared to a year ago ( OR = 0.4 ; 95 % Cl = 0.2 - 0.8 ) , individuals who exercised more frequently ( OR = 0.2 ; 95 % Cl = 0.1 - 0.7 ) , and those who used a walker ( OR = 0.3 ; 95 % CI = 0.1 - 0.9 ) . Conclusions : Results suggest that interventions that address  exercise frequency , walker use , and dizziness have promise for reducing falls for individuals with incomplete SCI OBJECTIVES ( 1 ) To determine the incidence of wheelchair falls and fall-related injuries in persons with spinal cord injury ( SCI ) living in the community . ( 2 ) To predict wheelchair-related falls and associated injuries from specific parameters including characteristics of the wheelchair user , wheelchair type and features , health care practice s , wheelchair activities , and physical environment . DESIGN This prospect i ve cohort study followed participants monthly over 1 year ; data were collected through surveys , interviews , performance testing , observation , and medical records . SETTING Three Veterans ' Administration hospitals . PARTICIPANTS Convenience sample 
    Output:
    