CLINICAL INVESTIGATION
Functional Reach: A Marker of Phvsical Frailtv J
J
Debra K.Weiner, MD,* Pamela W . Duncan, PhD,*t Julie Chandler, PT,t Stephanie A. Studenski, MD*$ Objective: To establish the concurrent validity of our new balance instrument, functional reach (FR = maximal safe standing forward reach), as a marker of physical frailty compared with other clinical measures of physical performance. Design, Setting and Participants: 45 community-dwelling persons age 66-104 were evaluated at one point in time using (1) FR (yardstick method), (2) Physical and Instrumental Activities of Daily Living (PADL, IADL), (3) Life Space, a 3point measure of social mobility, (4) 10-item hierarchical mobility skills protocol, (5) 10-foot walking speed, (6) onefooted standing, and (7)tandem walking. Data analysis em-
ployed Spearman correlations.Partial r's were also calculated after controllingfor age. Results: The FR performance range was broad (4.3-16.5 inches, mean 10.9, SD 3.1). Except for PADL, the association of FR with the other physical performance measures was strong, with r's ranging from 0.64-0.71; the association of FR with PADL was 0.48. After controlling for age in the regression analysis, partial Y'S ranged from 0.52-0.63. The association of FR with age was -0.50. Conclusions: Based on cross-sectional data, FR is a practical instrument that correlates with physical frailty even more than with age. J Am Geriatr SOC40203-207,1991
hysical frailty is a very real but poorly understood part of aging. It can be thought of as the result of accumulated losses within physiologic systems resulting in reduced function and intolerance to challenge.' Balance impairment resulting in falls represents one facet of physical frailty in older persons.2-9 In an effort to quantitate in a practical way this "balance frailty* in the elderly, we recently developed a new clinical tool called functional reach (FR)." FR is a balance measure that combines current dynamic postural control theory with a practical measurement s stem and demonstrates excellent test characteristics!' It represents the maximal distance an individual can reach forward beyond arm's length while maintaining a fixed base of support in the standing position. This measure was initially conceived because of the clinical observation that, from a biomechanical perspective, reaching tasks simulate age-sensitive leaning tasks used to assess postural control and measured traditionally with center of pressure excursion (COPE). But reaching adds a functional dimension to leaning, making it more relevant to the real world. In addition, F R s use of an extremely clinically accessible measurement system (a yardstick) allows its application in a wide variety of patient care settings. The initial phase of development of FR as a clinical balance measure involved its testing in healthy volunteers." One-hundred twenty-eight individuals age 2 187 were evaluated. The criterion validity of FR was established using COPE as the comparison standard. Test-retest reliability as well as interobserver reliability
were also established in this initial phase of instrument development. FR was found to be more precise and reliable than COPE. In addition, FR was age-sensitive, but this negative correlation was only modest (Pearson Y = -0.45). Having established FR as a precise and reliable clinical balance tool, we now enter into the second phase of this instrument's development. Balance represents a key component of physical performance and, therefore, physical frailty. In this project, we assess FRs concurrent validity as a marker of physical frailty by examining the relationship between FR and other physical performance measures in frail elderly. We sampled FR in a group of community-dwelling elderly with a range of physical impairments and analyzed the association between performance on the FR task and other clinical measures of physical performance as well as subjective performance on activities of daily living scales.
P
From the Tenter for the Study of Aging and Human Development and tGraduate Program in Physical Therapy, Duke University and the $Veterans Administration Medical Center, Durham, North Carolina Supported by a grant from the Andrew W. Mellon Foundation. Presented at the American Geriatrics Society Meeting, Atlanta, Georgia, May 1990. Address correspondence and reprint requests to Debra K. Weiner, MD, Duke University Medical Center, Box 3003, Durham, NC 27710.
IAGS 40203-207. 1992 Q 1992 by fhe American Geriatrics Society
MATERIALS AND METHODS
Subjects Community-dwelling volunteers were recruited from the Durham Veterans Administration Hospital Geriatrics Clinic, the Duke University Medical Center Medical Outpatient Clinics, and the Duke University Medical Center Geriatric Evaluation and Treatment Clinic. Subjects represented a sample of convenience; they were contacted on-site at the time of their clinic appointment, and excluded if they were less than 65 years of age, unable to stand unassisted for 60 seconds, unable to follow a two-step command, or could not raise their arm to 90 degrees. Test-retest reliability data was performed on thirteen inpatient volunteers recruited from the Durham Veterans Administration Extended Care and Rehabilitation Center (ECRC) who were not undergoing rehabilitation.
O002-8614/92f$3.50
204
WEINER ET AL
IAGS-MARCH 1992-VOL. 40, NO.3
Procedure Subjects were screened on site using the Folstein mental status examination." For scores
Functional Reach: A Marker of Phvsical Frailtv J
J
Debra K.Weiner, MD,* Pamela W . Duncan, PhD,*t Julie Chandler, PT,t Stephanie A. Studenski, MD*$ Objective: To establish the concurrent validity of our new balance instrument, functional reach (FR = maximal safe standing forward reach), as a marker of physical frailty compared with other clinical measures of physical performance. Design, Setting and Participants: 45 community-dwelling persons age 66-104 were evaluated at one point in time using (1) FR (yardstick method), (2) Physical and Instrumental Activities of Daily Living (PADL, IADL), (3) Life Space, a 3point measure of social mobility, (4) 10-item hierarchical mobility skills protocol, (5) 10-foot walking speed, (6) onefooted standing, and (7)tandem walking. Data analysis em-
ployed Spearman correlations.Partial r's were also calculated after controllingfor age. Results: The FR performance range was broad (4.3-16.5 inches, mean 10.9, SD 3.1). Except for PADL, the association of FR with the other physical performance measures was strong, with r's ranging from 0.64-0.71; the association of FR with PADL was 0.48. After controlling for age in the regression analysis, partial Y'S ranged from 0.52-0.63. The association of FR with age was -0.50. Conclusions: Based on cross-sectional data, FR is a practical instrument that correlates with physical frailty even more than with age. J Am Geriatr SOC40203-207,1991
hysical frailty is a very real but poorly understood part of aging. It can be thought of as the result of accumulated losses within physiologic systems resulting in reduced function and intolerance to challenge.' Balance impairment resulting in falls represents one facet of physical frailty in older persons.2-9 In an effort to quantitate in a practical way this "balance frailty* in the elderly, we recently developed a new clinical tool called functional reach (FR)." FR is a balance measure that combines current dynamic postural control theory with a practical measurement s stem and demonstrates excellent test characteristics!' It represents the maximal distance an individual can reach forward beyond arm's length while maintaining a fixed base of support in the standing position. This measure was initially conceived because of the clinical observation that, from a biomechanical perspective, reaching tasks simulate age-sensitive leaning tasks used to assess postural control and measured traditionally with center of pressure excursion (COPE). But reaching adds a functional dimension to leaning, making it more relevant to the real world. In addition, F R s use of an extremely clinically accessible measurement system (a yardstick) allows its application in a wide variety of patient care settings. The initial phase of development of FR as a clinical balance measure involved its testing in healthy volunteers." One-hundred twenty-eight individuals age 2 187 were evaluated. The criterion validity of FR was established using COPE as the comparison standard. Test-retest reliability as well as interobserver reliability
were also established in this initial phase of instrument development. FR was found to be more precise and reliable than COPE. In addition, FR was age-sensitive, but this negative correlation was only modest (Pearson Y = -0.45). Having established FR as a precise and reliable clinical balance tool, we now enter into the second phase of this instrument's development. Balance represents a key component of physical performance and, therefore, physical frailty. In this project, we assess FRs concurrent validity as a marker of physical frailty by examining the relationship between FR and other physical performance measures in frail elderly. We sampled FR in a group of community-dwelling elderly with a range of physical impairments and analyzed the association between performance on the FR task and other clinical measures of physical performance as well as subjective performance on activities of daily living scales.
P
From the Tenter for the Study of Aging and Human Development and tGraduate Program in Physical Therapy, Duke University and the $Veterans Administration Medical Center, Durham, North Carolina Supported by a grant from the Andrew W. Mellon Foundation. Presented at the American Geriatrics Society Meeting, Atlanta, Georgia, May 1990. Address correspondence and reprint requests to Debra K. Weiner, MD, Duke University Medical Center, Box 3003, Durham, NC 27710.
IAGS 40203-207. 1992 Q 1992 by fhe American Geriatrics Society
MATERIALS AND METHODS
Subjects Community-dwelling volunteers were recruited from the Durham Veterans Administration Hospital Geriatrics Clinic, the Duke University Medical Center Medical Outpatient Clinics, and the Duke University Medical Center Geriatric Evaluation and Treatment Clinic. Subjects represented a sample of convenience; they were contacted on-site at the time of their clinic appointment, and excluded if they were less than 65 years of age, unable to stand unassisted for 60 seconds, unable to follow a two-step command, or could not raise their arm to 90 degrees. Test-retest reliability data was performed on thirteen inpatient volunteers recruited from the Durham Veterans Administration Extended Care and Rehabilitation Center (ECRC) who were not undergoing rehabilitation.
O002-8614/92f$3.50
204
WEINER ET AL
IAGS-MARCH 1992-VOL. 40, NO.3
Procedure Subjects were screened on site using the Folstein mental status examination." For scores
