Showing papers by "James F. Fries published in 2008"
TL;DR: The methods of the PROMIS project are likely to substantially improve measures of physical function and to increase the efficiency of their administration using CAT.
394 citations
TL;DR: Vigorous exercise (running) at middle and older ages is associated with reduced disability in later life and a notable survival advantage.
Abstract: Background Exercise has been shown to improve many health outcomes and well-being of people of all ages. Long-term studies in older adults are needed to confirm disability and survival benefits of exercise. Methods Annual self-administered questionnaires were sent to 538 members of a nationwide running club and 423 healthy controls from northern California who were 50 years and older beginning in 1984. Data included running and exercise frequency, body mass index, and disability assessed by the Health Assessment Questionnaire Disability Index (HAQ-DI; scored from 0 [no difficulty] to 3 [unable to perform]) through 2005. A total of 284 runners and 156 controls completed the 21-year follow-up. Causes of death through 2003 were ascertained using the National Death Index. Multivariate regression techniques compared groups on disability and mortality. Results At baseline, runners were younger, leaner, and less likely to smoke compared with controls. The mean (SD) HAQ-DI score was higher for controls than for runners at all time points and increased with age in both groups, but to a lesser degree in runners (0.17 [0.34]) than in controls (0.36 [0.55]) ( P Conclusion Vigorous exercise (running) at middle and older ages is associated with reduced disability in later life and a notable survival advantage.
271 citations
TL;DR: Regression models found higher initial BMI, initial radiographic damage, and greater time from initial radiograph to be associated with worse radiographic OA at the final assessment, while the possibility that severe OA may not be more common among runners is raised.
145 citations
Journal Article•
TL;DR: In this article, a generalized partial credit model was used to estimate item parameters, which were normed to a mean of 50 (SD = 10) in the US population, which was not achieved over a similar range by any comparable fixed length item sets.
43 citations
TL;DR: Being physically active mitigated development of disability in these seniors, largely independent of BMI, suggesting public health efforts that promote physically active lifestyles among seniors may be more successful than those that emphasize body weight in the prevention of functional decline.
Abstract: Objectives. We examined the relationship of regular exercise and body weight to disability among healthy seniors. Methods. We assessed body mass index (BMI) and vigorous exercise yearly (1989‐2002) in 805 participants aged 50 to 72 years at enrollment. We studied 4 groups: normal-weight active (BMI 60 min/wk); normal-weight inactive (exercise ≤60 min/wk); overweight active (BMI ≥25 kg/m 2 ); and overweight inactive. Disability was measured with the Health Assessment Questionnaire (0‐3; 0 = no difficulty, 3 = unable to do). We used multivariable analysis of covariance to determine group differences in disability scores after adjustment for determinants of disability. Results. The cohort was 72% men and 96% White, with a mean age of 65.2 years. After 13 years, overweight active participants had significantly less disability than did overweight inactive (0.14 vs 0.19; P = .001) and normal-weight inactive (0.22; P = .03) participants. Similar differences were found between normal-weight active (0.11) and normal-weight inactive participants (P < .001). Conclusions. Being physically active mitigated development of disability in these seniors, largely independent of BMI. Public health efforts that promote physically active lifestyles among seniors may be more successful than those that emphasize body weight in the prevention of functional decline. (Am J Public Health. 2008;98:1294‐1299. doi:10.2105/AJPH.2007.119909)
38 citations
01 Jan 2008
TL;DR: Disability and survival curves continued to divergebetween groups after the 21-year follow-up asparticipants approached their ninth decade of life.
Abstract: Background:Exercisehasbeenshowntoimprovemany healthoutcomesandwell-beingofpeopleofallages.Longterm studies in older adults are needed to confirm disability and survival benefits of exercise. Methods:Annual self-administered questionnaires were sentto538membersofanationwiderunningcluband423 healthycontrolsfromnorthernCaliforniawhowere50years and older beginning in 1984. Data included running and exercise frequency, body mass index, and disability assessed by the Health Assessment Questionnaire Disability Index (HAQ-DI; scored from 0 [no difficulty] to 3 [unabletoperform])through2005.Atotalof284runnersand 156 controls completed the 21-year follow-up. Causes of death through 2003 were ascertained using the National Death Index. Multivariate regression techniques compared groups on disability and mortality. Results:At baseline, runners were younger, leaner, and less likely to smoke compared with controls. The mean (SD)HAQ-DIscorewashigherforcontrolsthanforrunners at all time points and increased with age in both groups, but to a lesser degree in runners (0.17 [0.34]) than in controls (0.36 [0.55]) (P.001). Multivariate analyses showed that runners had a significantly lower risk of an HAQ-DI score of 0.5 (hazard ratio, 0.62; 95% confidence interval, 0.46-0.84). At 19 years, 15% of runners had died compared with 34% of controls. After adjustment for covariates, runners demonstrated a survivalbenefit(hazardratio,0.61;95%confidenceinterval, 0.45-0.82). Disability and survival curves continued to divergebetweengroupsafterthe21-yearfollow-upasparticipants approached their ninth decade of life.
28 citations
TL;DR: Comparing the Health Assessment Questionnaire disability index and the Short Form 36 physical functioning subscale using Rasch analysis in a small cross-sectional study suggests that the analysis favors the SF-36 PF over the HAQ DI in psoriatic arthritis, and confirms the authors’ belief that the HAZ DI has its greatest item information content in sicker populations and theSF-36PF in more normalized ones.
Abstract: In a recent article in Arthritis Care & Research, Taylor and McPherson (1) compared the Health Assessment Questionnaire disability index (HAQ DI) and the Short Form 36 (SF-36) physical functioning subscale (PF) using Rasch analysis in a small cross-sectional study, suggesting that the analysis favors the SF-36 PF over the HAQ DI in psoriatic arthritis (PsA). Studies such as this bring item response theory approaches to analyses of patient-reported outcomes. Although this effort is by itself meritorious, it carries the hazard that relatively unfamiliar terminology may obscure rather than illuminate. Under some circumstances, Rasch analysis has posed unacceptable threats to content through trimming of items to a more unidimensional construct, which then lacks face and content validity (2). Some of us would argue that sensitivity to change, face and content validity, and reliability, not studied by Taylor and McPherson, are among the most essential attributes of an outcome assessment instrument, and that item separation, ceiling and floor effects, and differential item functioning, although not unimportant, are less essential. Furthermore, the authors’ analyses and interpretations misunderstand the construction of the HAQ DI, which was designed to balance content across categories into a single score, not to be disaggregated into subdimensions (profiles). HAQ DI categories were not designed to be ranked or separately reported, but to ensure attention to all major content areas of disability. The PsA patients compared with the rheumatoid arthritis patients had on average much better physical functioning (HAQ DI score 0.5 versus 1.23), raising issues of different performance in different populations. This cross-sectional study cannot get at the most critical outcome assessment issues nor lead to definitive conclusions. That being said, there are useful insights here. First, an unresolved clinical issue with PsA is whether we should assess only the arthritis or some sum of the skin and the joint disease. If it is the latter, a health-related quality of life instrument might perform strongly. Second, where disability is near the population norm, an instrument designed for more normal populations (SF-36 PF) might perform well. Third, we agree that floor and ceiling effects have received less attention than warranted. Figure 1 shows measurement precision, where a standard error of 2.3 corresponds to reliability of Cronbach’s alpha of 0.95 graphed against theta values, normalized so that 50 represents the average functioning of a normal population and each set of 10 units represents 1 standard deviation (3). The best instrument would have the lowest and broadest curve; the lowest point shows the degree of physical functioning where information content is maximal and greater breadth reduces floor and ceiling effects. These data confirm the authors’ belief that the HAQ DI has its greatest item information content in sicker populations and the SF-36 PF in more normalized ones, and that floor effects are more common with the HAQ DI than the SF-36 PF. Most importantly, use of computer-adaptive testing, where items are dynamically selected for the individual based upon prior responses, can readily outperform static instruments using a similar number of items. The National Institutes of Health Patient-Reported Outcomes Measurement Information System (PROMIS) is approaching these issues with qualitative as well as quantitative item review and calibration, with the best of the HAQ DI and the SF-36 PF together with other items used in dynamic (computer-adaptive testing) rather than static instruments. These instruments will clearly supersede our present standards. PROMIS item banks are in the public domain and may be accessed at www.nihPROMIS.org and at ARAMIS.Stanford.edu for the PROMIS HAQ. We have entered an era of higher performance standards for patientreported outcomes and better outcome measures for studies.
3 citations