John P. Holcomb

A Randomized Controlled Trial of Functional Neuromuscular Stimulation in Chronic Stroke Subjects

Background and Purpose— Conventional therapies fail to restore normal gait to many patients after stroke. The study purpose was to test response to coordination exercise, overground gait training, and weight-supported treadmill training, both with and without functional neuromuscular stimulation (FNS) using intramuscular (IM) electrodes (FNS-IM). Methods— In a randomized controlled trial, 32 subjects (>1 year after stroke) were assigned to 1 of 2 groups: FNS-IM or No-FNS. Inclusion criteria included ability to walk independently but inability to execute a normal swing or stance phase. All subjects were treated 4 times per week for 12 weeks. The primary outcome measure, obtained by a blinded evaluator, was gait component execution, according to the Tinetti gait scale. Secondary measures were coordination, balance, and 6-minute walking distance. Results— Before treatment, there were no significant differences between the 2 groups for age, time since stroke, stroke severity, and each study measure. FNS-IM produced a statistically significant greater gain versus No-FNS for gait component execution (P=0.003; parameter estimate 2.9; 95% CI, 1.2 to 4.6) and knee flexion coordination (P=0.049). Conclusion— FNS-IM can have a significant advantage versus No-FNS in improving gait components and knee flexion coordination after stroke.

Recovery of Coordinated Gait: Randomized Controlled Stroke Trial of Functional Electrical Stimulation (FES) Versus No FES, With Weight-Supported Treadmill and Over-Ground Training

Background. No single intervention restores the coordinated components of gait after stroke. Objective. The authors tested the multimodal Gait Training Protocol, with or without functional electrical stimulation (FES), to improve volitional walking (without FES) in patients with persistent (>6 months) dyscoordinated gait. Methods. A total of 53 subjects were stratified and randomly allocated to either FES with intramuscular (IM) electrodes (FES-IM) or No-FES. Both groups received 1.5-hour training sessions 4 times a week for 12 weeks of coordination exercises, body weight–supported treadmill training (BWSTT), and over-ground walking, provided with FES-IM or No-FES. The primary outcome was the Gait Assessment and Intervention Tool (G.A.I.T.) of coordinated movement components, with secondary measures, including manual muscle testing, isolated leg movements (Fugl-Meyer scale), 6-Minute Walk Test, and Locomotion/Mobility subscale of the Functional Independence Measure (FIM). Results. No baseline differences in subject characteristics and measures were found. The G.A.I.T. showed an additive advantage with FES-IM versus No-FES (parameter statistic 1.10; P = .045, 95% CI = 0.023-2.179) at the end of training. For both FES-IM and No-FES, a within-group, pre/posttreatment gain was present for all measures (P < .05), and a continued benefit from mid- to posttreatment (P < .05) was present. For FES-IM, recovered coordinated gait persisted at 6-month follow-up but not for No-FES. Conclusion. Improved gait coordination and function were produced by the multimodal Gait Training Protocol. FES-IM added significant gains that were maintained for 6 months after the completion of training.

Comparison of Robotics, Functional Electrical Stimulation, and Motor Learning Methods for Treatment of Persistent Upper Extremity Dysfunction After Stroke: A Randomized Controlled Trial

OBJECTIVE To compare response to upper-limb treatment using robotics plus motor learning (ML) versus functional electrical stimulation (FES) plus ML versus ML alone, according to a measure of complex functional everyday tasks for chronic, severely impaired stroke survivors. DESIGN Single-blind, randomized trial. SETTING Medical center. PARTICIPANTS Enrolled subjects (N=39) were >1 year postsingle stroke (attrition rate=10%; 35 completed the study). INTERVENTIONS All groups received treatment 5d/wk for 5h/d (60 sessions), with unique treatment as follows: ML alone (n=11) (5h/d partial- and whole-task practice of complex functional tasks), robotics plus ML (n=12) (3.5h/d of ML and 1.5h/d of shoulder/elbow robotics), and FES plus ML (n=12) (3.5h/d of ML and 1.5h/d of FES wrist/hand coordination training). MAIN OUTCOME MEASURES Primary measure: Arm Motor Ability Test (AMAT), with 13 complex functional tasks; secondary measure: upper-limb Fugl-Meyer coordination scale (FM). RESULTS There was no significant difference found in treatment response across groups (AMAT: P≥.584; FM coordination: P≥.590). All 3 treatment groups demonstrated clinically and statistically significant improvement in response to treatment (AMAT and FM coordination: P≤.009). A group treatment paradigm of 1:3 (therapist/patient) ratio proved feasible for provision of the intensive treatment. No adverse effects. CONCLUSIONS Severely impaired stroke survivors with persistent (>1y) upper-extremity dysfunction can make clinically and statistically significant gains in coordination and functional task performance in response to robotics plus ML, FES plus ML, and ML alone in an intensive and long-duration intervention; no group differences were found. Additional studies are warranted to determine the effectiveness of these methods in the clinical setting.

Development and Testing of The Gait Assessment and Intervention Tool (G.A.I.T.): A Measure of Coordinated Gait Components

Recent neuroscience methods have provided the basis upon which to develop effective gait training methods for recovery of the coordinated components of gait after neural injury. We determined that there was not an existing observational measure that was, at once, adequately comprehensive, scored in an objectively-based manner, and capable of assessing incremental improvements in the coordinated components of gait. Therefore, the purpose of this work was to use content valid procedures in order to develop a relatively inexpensive, more comprehensive measure, scored with an objectively-based system, capable of incrementally scoring improvements in given items, and that was both reliable and capable of discriminating treatment response for those who had a stroke. Eight neurorehabilitation specialists developed criteria for the gait measure, item content, and scoring method. In subjects following stroke (>12 months), the new measure was tested for intra- and inter-rater reliability using the Intraclass Correlation Coefficient; capability to detect treatment response using Wilcoxon Signed Ranks Test; and discrimination between treatment groups, using the Plum Ordinal Regression. The Gait Assessment and Intervention Tool (G.A.I.T.) is a 31-item measure of the coordinated movement components of gait and associated gait deficits. It exhibited the following advantages: comprehensive, objective-based scoring method, incremental measurement of improvement within given items. The G.A.I.T. had good intra- and inter-rater reliability (ICC=.98, p=.0001, 95% CI=.95, .99; ICC=.83, p=.007, 95% CI=.32, .96, respectively. The inexperienced clinician who had training, had an inter-rater reliability with an experienced rater of ICC=.99 (p=.0001, CI=.97, .999). The G.A.I.T. detected improvement in response to gait training for two types of interventions: comprehensive gait training (z=-2.93, p=.003); and comprehensive gait training plus functional electrical stimulation (FES; z=-3.3, p=.001). The G.A.I.T. was capable of discriminating between two gait training interventions, showing an additive advantage of FES to otherwise comparable comprehensive gait training (parameter estimate=1.72, p=.021; CI, .25, 3.1).

Using a Term-Long Project Sequence in Introductory Statistics

Abstract We propose a series of projects for introductory data analysis classes using a single, real multivariate dataset. The assignments combine four current trends in statistics education: Computers, real data, collaborative learning, and writing. Completing the project sequence allows students to appreciate and understand the interconnectedness of statistical concepts. We present rationale for the assignments including five objectives. We provide institutional and course background, an explanation of the data source and variables, grading criteria, a summary of each project, and an assessment of student learning. We conclude with a Web address to facilitate implementation of this approach.

Rethinking Assessment of Student Learning in Statistics Courses

Although much attention has been paid to issues around student assessment, for most introductory statistics courses few changes have taken place in the ways students are assessed. The assessment literature describes three foundational elements—cognition, observation, and interpretation—that comprise an “assessment triangle” underlying all assessments. However, most instructors focus primarily on the second component: tasks that are used to produce grades. This article focuses on three sections written by leading statistics educators who describe some innovative and even provocative approaches to rethinking student assessment in statistics classes.

Food Insecurity Is Associated with Health Status of Older Adults Participating in The Commodity Supplemental Food Program in A Rural Appalachian Ohio County

ABSTRACT Context. Food insecurity is associated with poorer nutritional and health status among older adults. Objectives. To assess the household food security and health status of older adults participating in the Commodity Supplemental Food Program (CSFP) and to determine the relationship of these factors. Design. A telephone survey conducted during Spring 2004 that included the 18-item Food Security Survey Module and SF-36 health status questionnaire. Setting. Athens County, Ohio, located in rural, Appalachian Ohio. Participants. Convenience sample of older adults 60 years and older [n = 91; 71.0y (8.1 SD)] receiving CSFP benefits and living in households located in Athens County, Ohio. Main Outcome Measures. Household food security status (U.S. Household Food Security Survey Module) and health status (SF-36) (physical and mental health scores in eight areas: Physical functioning, role-physical, bodily pain, general health, vitality, social functioning, role-emotional, mental health). It was hypothesized that food insecurity would be associated with poorer health status. Results. Forty-six (50.5%), 36 (39.6%), and 9 (9.9%) subjects were from food secure, food insecure without hunger, and food insecure with hunger households, respectively. Consistent with other reports, all health scores worsened as household food security status worsened (physical functioning, p = .018; role-physical, p = .005; bodily pain, p < .001; general health, p < .001; vitality, p = .029; social functioning, p = .009; role-emotional, p = .007; mental health, p = .009), and health status was greater for those from food secure compared with food insecure households for 7 of 8 scores (physical functioning, p = .025; role-physical, p = .016; bodily pain, p = .002; general health, p < .001; social functioning, p = .014; role-emotional, p = .006; mental health, p = .003). Conclusions. This study further supports that food insecurity is related to poorer health among older adults. Further research in a larger sample of older adults participating in CSFP is warranted, as are other studies of those participating in food assistance programs.

Physician Treatment of Osteoporosis in Response to Heel Ultrasound Bone Mineral Density Reports

Optimal information that should be included in ultrasound (US) heel bone mineral density (BMD) reports is not known. If additional information about further evaluation of patients with low heel BMD were included in reports, would responses for treatment improve? We screened people at health fairs using the Sahara heel US machine. For those with a T-score of </= 1.0, letters were sent to their primary care physician notifying them of the result. Physicians were randomly assigned to (1) a standard letter, which recommended central bone density screening (dual X-ray absorptiometry [DXA]) and treatment if the BMD was low; or (2) an extended letter, which also outlined treatment strategies based on recommended subsequent central DXA scan results for a T-score of < 1.50 and also if < 2.00. The extended letter only increased the frequency of DXA testing from 30.1 to 37.2% (not a significant increase). Of 88 people with heel BMD </= 1.00 and not previously on any treatment, 25 of 45 (56%) were treated (calcium, estrogens, bisphosphonates, or calcitonin or a combination) after physicians received a standard letter and 30 of 43 (70%) after an extended letter (one-sided p = 0.084). Of people with T </= 1.9, and initially taking nothing more than calcium, 5 of 36 (13.9%) received additional treatment after physicians received a standard letter vs 9 of 41 (22.0%) after an extended letter (one-sided p = 0.180). For those with T </= 1.0 because of the screen 25 of 197 (12.7%) received additional treatment. One hundred forty-six of 194 (75%) individuals and received treatment with calcium or other medications, and 74 of 173 (43%) of individuals before screening and 141 of 195 (72%) after physicians received letters took calcium. Physicians regarded calcium alone as adequate treatment in many cases. There was no marked increase in treatment when additional information was provided to physicians regarding evaluation and treatment for low US heel BMD results.

Logistic Regression Analysis: When the Odds Ratio Does Not Work An Example Using Intimate Partner Violence Data

The odds ratio is one of the most common measures used to assess the relationship between exposure to violence and adverse health outcomes, adjusting for possible confounding factors. A reason for the odds ratios popularity is that it is relatively easy to calculate from the coefficients of a logistic regression model. For most etiologic studies of disease, the odds ratio is a suitable estimate of risk because incidence or prevalence of disease is rare (<10%). However, health outcomes studied in violence research are often more prevalent (e.g., fatigue, insomnia, stomach pain, and shortness of breath). In these cases, the odds ratio usually overestimates the strength of association, sometimes erroneously tripling the magnitude. Data from a study measuring the health effects of intimate partner violence are used to illustrate the problem of incorrectly using odds ratios. Methods to calculate relative risks and prevalence ratios from logistic regression models are presented.

Regression with Covariates and Outcome Calculated from a Common Set of Variables Measured with Error: Estimation Using the SIMEX Method

In medical research, a situation commonly arises where new variables are calculated from a common set of directly measured variables. When the directly measured variables each contain an error component, the relationship between the observed calculated variables can often be distorted. A source of this distortion is the presence of common measurement error in the observed calculated variables. Often known as coupled error, it is still possible to estimate the relationship between the calculated variables when measurement error is present. This paper presents two general methodologies that account for the presence of correlated measurement error when working with calculated variables. The equivalence of the methods will be established for one case, while the general advantage of the simulation extrapolation technique will be shown for more complicated situations. The performance of the estimators will be examined with examples arising from the medical literature.