Dennis Wallace

Physical Performance Measures in the Clinical Setting

OBJECTIVES:  To assess the ability of gait speed alone and a three‐item lower extremity performance battery to predict 12‐month rates of hospitalization, decline in health, and decline in function in primary care settings serving older adults.

The Stroke Impact Scale Version 2.0 Evaluation of Reliability, Validity, and Sensitivity to Change

BACKGROUND AND PURPOSE To be useful for clinical research, an outcome measure must be feasible to administer and have sound psychometric attributes, including reliability, validity, and sensitivity to change. This study characterizes the psychometric properties of the Stroke Impact Scale (SIS) Version 2.0. METHODS Version 2.0 of the SIS is a self-report measure that includes 64 items and assesses 8 domains (strength, hand function, ADL/IADL, mobility, communication, emotion, memory and thinking, and participation). Subjects with mild and moderate strokes completed the SIS at 1 month (n=91), at 3 months (n=80), and at 6 months after stroke (n=69). Twenty-five subjects had a replicate administration of the SIS 1 week after the 3-month or 6-month test. We evaluated internal consistency and test-retest reliability. The validity of the SIS domains was examined by comparing the SIS to existing stroke measures and by comparing differences in SIS scores across Rankin scale levels. The mixed model procedure was used to evaluate responsiveness of the SIS domain scores to change. RESULTS Each of the 8 domains met or approached the standard of 0.9 alpha-coefficient for comparing the same patients across time. The intraclass correlation coefficients for test-retest reliability of SIS domains ranged from 0.70 to 0.92, except for the emotion domain (0.57). When the domains were compared with established outcome measures, the correlations were moderate to strong (0.44 to 0.84). The participation domain was most strongly associated with SF-36 social role function. SIS domain scores discriminated across 4 Rankin levels. SIS domains are responsive to change due to ongoing recovery. Responsiveness to change is affected by stroke severity and time since stroke. CONCLUSIONS This new, stroke-specific outcome measure is reliable, valid, and sensitive to change. We are optimistic about the utility of measure. More studies are required to evaluate the SIS in larger and more heterogeneous populations and to evaluate the feasibility and validity of proxy responses for the most severely impaired patients.

Comparison of the responsiveness of the Barthel Index and the Motor Component of the Functional Independence Measure in stroke: The impact of using different methods for measuring responsiveness

Two disability measures frequently used to assess the effects of interventions on stroke recovery are the Barthel Index (BI) and the motor component of the Functional Independence Measure (FIM Instrument). This study compared multiple measures of responsiveness of these instruments to stroke recovery between 1 and 3 months. Data on a 1- to 3-month change in the Instruments were obtained for 372 subjects who improved or maintained function on the modified Rankin Scale (MRS), using a subset of 459 eligible patients with confirmed stroke as defined by WHO criteria recruited from 12 participating hospitals in the Greater Kansas City area. Subjects were excluded because of death, early withdrawal from the study, missing MRS, or outcome data (57) decline on MRS (26), or inability to improve on MRS (4). Techniques used to assess responsiveness were: area under the ROC curve, Guyatts effect size, paired t-statistics, standardized response mean, Kazis effect size, and mixed model adjusted t-statistic. The FIM Instrument and BI show little difference in responsiveness to change. The different responsiveness measures are generally consistent with this conclusion, with no measure clearly superior to the others. Large differences in the responsiveness measures were obtained within an instrument depending on the populations used (changers only or both changers and those who maintained function). Results also suggest responsiveness assessments are likely to be affected by time frame and phase of rehabilitation over which the responsiveness of a measure is determined.

To House or Not to House: The Effects of Providing Housing to Homeless Substance Abusers in Treatment

OBJECTIVES Housing typically is not provided to homeless persons during drug abuse treatment. We examined how treatment outcomes were affected under 3 different housing provision conditions. METHODS We studied 196 cocaine-dependent participants who received day treatment and no housing (NH), housing contingent on drug abstinence (ACH), or housing not contingent on abstinence (NACH). Drug use was monitored with urine testing. RESULTS The ACH group had a higher prevalence of drug abstinence than the NACH group (after control for treatment attendance), which in turn had a higher prevalence than the NH group. All 3 groups showed significant improvement in maintaining employment and housing. CONCLUSIONS The results of this and previous trials indicate that providing abstinence-contingent housing to homeless substance abusers in treatment is an efficacious, effective, and practical intervention. Programs to provide such housing should be considered in policy initiatives.

Co-morbidity adjustment for functional outcomes in community-dwelling older adults

Objective: To characterize relationships between self-reported co-morbidity and functional outcomes in community-dwelling older adults, and to assess whether the impact of co-morbidity persists even after adjustment for baseline functional status. Design: Prospective observational study. We examined associations between self-reported co-morbidity at baseline and functional outcomes at one year, with and without adjustment for baseline functional status. Setting: Outpatient clinics at a managed care and a Veterans Affairs site. Subjects: Four hundred and ”fty-seven community-dwelling older adults representing a broad spectrum of overall health status. Main outcome measures: (a) New basic ADL (activities of daily living) problem during follow-up; (b) 10-point decline in the physical function index of the MOS-36 (MOS-PFI). Results: Co-morbidity was associated with adverse functional outcomes in bivariable analyses. After adjustment for age and baseline functional status, an accumulated co-morbidity score provided additional explanatory power for predicting new ADL problems; odds ratios were 2.30 (1.09, 5.09) and 2.96 (1.48, 6.25) for 2 and 33 affected co-morbidity domains, respectively. The impact of baseline status was also important; odds ratios for new ADL problems were 4.77 (2.68, 8.81) when at least one instrumental activity of daily living (IADL) problem was present at baseline, and 15.6 (8.05, 31.3) when at least one basic ADL problem was present at baseline. Conclusions: Accumulated self-reported co-morbidity has signi”cant negative effects on function at one year; these effects are attenuated but not eliminated by adjustment for baseline status. Co-morbidity adjustment is probably an important design element in clinical research focused on functional outcomes in older adults.

Smoking Status as a Vital Sign

AbstractOBJECTIVE: We conducted this study to determine if a smoking status stamp would prompt physicians to increase the number of times they ask, advise, assist, and arrange follow-up for African-American patients about smoking-related issues. DESIGN: An intervention study with a posttest assessment (after the physician visit) conducted over four 1-month blocks. The control period was the first 2 weeks of each month, while the following 2 weeks served as the intervention period. SETTING: An adult walk-in clinic in a large inner-city hospital. PARTICIPANTS: We consecutively enrolled into the study 2,595 African-American patients (1,229 intervention and 1,366 control subjects) seen by a housestaff physician. INTERVENTIONS: A smoking status stamp placed on clinic charts during the intervention period. MAIN RESULTS: Forty-five housestaff rotated through the clinic in 1-month blocks. In univariate analyses, patients were significantly more likely to be asked by their physicians if they smoke cigarettes during the intervention compared with the control period, 78.4% versus 45.6% (odds ratio [OR] 4.28; 95% confidence interval [CI] 3.58, 5.10). Patients were also more likely to be told by their physician to quit, 39.9% versus 26.9% (OR 1.81; 95% CI 1.36, 2.40), and have follow-up arranged, 12.3% versus 6.2% (OR 2.16; 95% CI 1.30, 3.38). CONCLUSIONS: The stamp had a significant effect on increasing rates of asking about cigarette smoking, telling patients to quit, and arranging follow-up for smoking cessation. However, the stamp did not improve the low rate at which physicians offered patients specific advice on how to quit or in setting a quit date.

Factors Influencing Infant Visits to Emergency Departments

Objectives. To follow the 1995 birth cohort of infants, born in the State of Missouri, through their first birthday to: 1) examine their rates of visits to emergency departments (EDs), 2) identify predictors of any ED visit, 3) examine rates of nonurgent ED visits, and 4) identify predictors of nonurgent visits. Methods. This was a retrospective population cohort study. Using deterministic linkage procedures, 2 databases at the Missouri Department of Health (DOH; (the patient abstract database and the birth registry database) were linked by DOH personnel. International Classification of Diseases, Ninth Revision-Clinical Modification codes for ED visits were classified as emergent, urgent, or nonurgent by 2 researchers. Eight newborn characteristics were chosen for analysis. Negative binomial regression was used to examine the rates and predictors of both total and nonurgent ED visits. Results. There were 935 total ED visits and 153 nonurgent ED visits per 1000 infant years. The average number of visits was .94, with 59% of infants having no visits, 21% having 1 ED visit, and 20% having 2 or more visits. Factors associated with increases in both total and nonurgent ED visits were Medicaid, self-pay, black race, rural region, presence of birth defects, and a nursery stay of >2 days. Significant interactions were found between Medicaid and race and Medicaid and rural regions on rates of ED use and nonurgent use. The highest rate of ED use, 1.8 per person year, was seen in white, rural infants on Medicaid, and the lowest rate (.4 per person year) was seen in urban white infants not on Medicaid. The highest rates of nonurgent use, .3 per person year, were among urban and rural Medicaid infants of both races and among black infants on commercial insurance. The lowest nonurgent rate, .04 per person year, was seen in white urban infants on commercial insurance. Conclusion. Infants in the State of Missouri have high rates of ED visits. Nonurgent visits are only a small portion of ED visits and cannot explain large variations in ED usage. Increased ED use by Medicaid patients may reflect continuing difficulties in accessing primary care.

Conceptualization of a New Stroke-Specific Outcome Measure: The Stroke Impact Scale

Abstract Current stroke outcome measures are unable to detect some consequences of stroke that affect patients, families, and providers. The objective of this study was to ensure the content validity of a new stroke outcome measure. This was a qualitative study using individual interviews with patients and focus group interviews with patients, caregivers, and health care professionals. Participants included 30 individuals with mild and moderate stroke, 23 caregivers, and 9 stroke experts. Qualitative analysis of the individual and focus group interviews generated a list of potential items. Consensus panels reviewed the potential items, established domains for the measure, developed item scales, and decided on mechanisms for administration and scoring. Although the participants with stroke appeared highly recovered based on scores from conventional stroke assessments (Barthel Index and NIH Stroke Scale), stroke survivors and their caregivers identified numerous persisting impairments, disabilities, and handicaps. In general, stroke survivors described themselves as only about 50% recovered and reported that they had difficulty in activities in which they were not independent. To fully assess the impact of stroke on patients, we used the results of this qualitative study to develop a new stroke-specific outcome, the Stroke Impact Scale.

Meta-analysis of day treatment and contingency-management dismantling research: Birmingham Homeless Cocaine Studies (1990-2006).

Four successive randomized clinical trials studying contingency management (CM), involving various treatment arms of drug-abstinent housing and work therapy and day treatment (DT) with a behavioral component, were compared on common drug abstinence outcomes at 2 treatment completion points (2 and 6 months). The clinical trials were conducted from 1990 to 2006 in Birmingham, Alabama, with a total of 644 homeless persons with primary crack cocaine addiction. The meta-analysis utilized the weighted least squares approach to integrate data encompassing 9 different treatment arms to assess the effects of CM and DT (neither, DT only, CM only, and CM = DT) on a common estimate of prevalence of drug abstinence. Taken together, the results show much stronger benefits from CM = DT and from CM only than for DT alone. Throughout all of the Birmingham Homeless Cocaine Studies, the CM = DT consistently produced higher abstinence prevalence than did no CM.

Interpreting age, period and cohort effects in plasma lipids and serum insulin using repeated measures regression analysis: the CARDIA study

Observed changes in health-related behaviours and disease risk factors may arise from physiological or environmental changes, or from biases due to sampling or measurement errors. We illustrate problems in the interpretation of such changes with longitudinal data from the Coronary Artery Risk Development in Young Adults (CARDIA) study. Mean plasma cholesterol was 14 mg/dl higher in 27- than in 20-year-old black men cross-sectionally, but longitudinally it declined by 4 mg/dl during the 7 years. To sort out these contradictory assessments of the effect of age/passage of time, we estimated age and period effects under the assumptions that age effects are a smooth function of age independent of period, and that period effects are changes common to persons across all ages. Simple estimates the age effect, such as the cross-sectional age slopes, may be confounded by cohort effects, by interactions of time and age after baseline, or by the occurrence of non-linearities in response after baseline. We note examples of each potential type of bias. The data and background literature support the assumption that cohort effects do not seriously compromise interpretation for these variables in the CARDIA study. Strong secular decreases in plasma cholesterol, apparently due to population-wide dietary change, mask increases with ageing. Age increases in triglycerides are largely explained by increases in body fatness. For these data, we cautiously accept the cross-sectional age slope as an estimate of ageing and the age-matched time trend as an estimate of secular trend.