Do proxies reflect patients' health concerns about urinary incontinence and gait problems?
BACKGROUND
While falls and urinary incontinence are prevalent among older patients, who sometimes rely on proxies to provide their health information, the validity of proxy reports of concern about falls and urinary incontinence remains unknown.


METHODS
Telephone interviews with 43 consecutive patients with falls or fear of falling and/or bothersome urinary incontinence and their proxies chosen by patients as most knowledgeable about their health. The questionnaire included items derived from the Medical Outcomes Study Short Form 12 (SF-12), a scale assessing concerns about urinary incontinence (UI), and a measure of fear of falling, the Falls Efficacy Scale (FES). Scores were estimated using items asking the proxy perspective (6 items from the SF-12, 10 items from a UI scale, and all 10 FES items). Proxy and patient scores were compared using intraclass correlation coefficients (ICC, one-way model). Variables associated with absolute agreement between patients and proxies were explored.


RESULTS
Patients had a mean age of 81 years (range 75-93) and 67% were female while proxies had a mean age of 70 (range 42-87) and 49% were female. ICCs were 0.63 for the SF-12, 0.52 for the UI scale, and 0.29 for the FES. Proxies tended to understate patients' general health and incontinence concern, but overstate patients' concern about falling. Proxies who lived with patients and those who more often see patients more closely reflected patient FES scores compared to those who lived apart or those who saw patients less often. Internal consistency reliability of proxy responses was 0.62 for the SF-12, 0.86 for the I-QOL, and 0.93 for the FES. In addition, construct validity of the proxy FES scale was supported by greater proxy-perceived fear of falling for patients who received medical care after a fall during the past 12 months (p < .05).


CONCLUSIONS
Caution should be exercised when using proxies as a source of information about older patients' health perceptions. Questions asking about proxies' views yield suboptimal agreement with patient responses. However, proxy scales of UI and fall concern are internally consistent and may provide valid independent information.
Higashi
Takahiro
T
Department of Epidemiology and Healthcare Research, Kyoto University, Kyoto, 606-8501, Japan. thigashi@pbh.med.kyoto-u.ac.jp
Hays
Ron D
RD
Brown
Julie A
JA
Kamberg
Caren J
CJ
Pham
Chau
C
Reuben
David B
DB
Shekelle
Paul G
PG
Solomon
David H
DH
Young
Roy T
RT
Roth
Carol P
CP
Chang
John T
JT
MacLean
Catherine H
CH
Wenger
Neil S
NS
D000058:Accidental Falls; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D005239:Fear; D005260:Female; D020233:Gait Disorders, Neurologic / Q000523:psychology*; D006801:Humans; D007407:Interviews as Topic; D008297:Male; D008875:Middle Aged; D019727:Proxy; D011788:Quality of Life / Q000523:psychology*; D018434:Sickness Impact Profile; D014549:Urinary Incontinence / Q000523:psychology*