Lois Finch

Incorporating the International Classification of Functioning, Disability, and Health (ICF) into an Electronic Health Record to Create Indicators of Function: Proof of Concept Using the SF-12

OBJECTIVE The purpose of this proof-of-concept study was to assess the feasibility of using a generic health measure to create coded functional status indicators and compare the characterization of a stroke population using coded functional indicators and using health-related quality-of-life summary measures alone. DESIGN Multiple raters assigned International Classification of Functioning, Disability, and Health (ICF) codes to the items of the 12-Item Short Form Health Survey (SF-12). Data for comparing the information from the SF-12 and from ICF codes were derived from the Montreal Stroke Cohort Study that was set up to examine the long-term impact of stroke. Available for analysis were data from 604 persons with stroke, average age 69 years, and 488 controls, average age 62 years. MEASUREMENT The SF-12 provides two summary scores, one for physical health and one for mental health. Domains of the ICF are coded to three digits, before the decimal; specific categorizations of impairments, activity limitations, and participation restrictions are coded to four digits before the decimal. RESULTS Persons with stroke scored, on average, approximately 10 points lower than controls on physical and mental health. The ICF coding indicated that this was attributed, not surprisingly, to greater difficulty in doing moderate activities including housework, climbing stairs, and working and was not attributed to differences in pain. Differences in mental health were attributed most strongly to greater fatigue (impairment in energy), but all areas of mental health were affected to some degree. CONCLUSION The ICF coding provided enhanced functional status information in a format compatible with the structure of administrative health databases.

Measuring Cognition in a Geriatric Outpatient Clinic: Rasch Analysis of the Montreal Cognitive Assessment

Objective: To evaluate the psychometric properties of the Montreal Cognitive Assessment as a quantitative measure of cognitive ability. Data analyzed: A total of 222 cases extracted from a clinical database (57-91 years) of patients screened for cognitive impairment in outpatient geriatric assessment clinics. Data collected: Demographic information and individual item responses to Montreal Cognitive Assessment. Results: Comparison of the data with a unidimensional Rasch model indicated that the total score obtained by summing across all items yields a reliable (0.75) quantitative estimate of global cognitive ability. All items fit the model and together spanned a range of difficulty from -3.75 to +2.88 logits. Items were assessed for differential item functioning across such patient characteristics as age, education, and language spoken. We provide a table for converting Montreal Cognitive Assessment total scores onto a linearly scaled score, with guidelines for interpreting changes in Montreal Cognitive Assessment score in terms of their statistical significance. Conclusions: The Montreal Cognitive Assessment can provide a reliable and valid quantitative estimate of cognitive ability in a geriatric cognitive disorders clinic setting.

Relationship between muscle strength and functional walking capacity among people with stroke

The purpose of this study was to estimate, using the Position-Specific Global Index (PSGI) of Lower-Limb Muscle Strength, the extent to which muscle strength is independently associated with functional walking capacity. We performed an observational, cross-sectional study with 63 patients poststroke (onset between 3 and 12 months) at a major teaching hospital in an urban Canadian city. We assessed functional walking capacity with the six-minute walk test (6MWT) and muscle strength with handheld dynamometry. We established the relationship between the lower-limb muscles and functional walking capacity with the PSGI. The PSGI explained 70% (p < 0.001) of the variability in the 6MWT, whereas the index of alternate against-gravity muscle strength explained 39% and the hip flexors in a supine position explained 51%.

A measure of early physical functioning (EPF) post-stroke.

OBJECTIVE To develop a comprehensive measure of Early Physical Functioning (EPF) post-stroke quantified through Rasch analysis and conceptualized using the International Classification of Functioning Disability and Health (ICF). DESIGN An observational cohort study. SUBJECTS A cohort of 262 subjects (mean age 71.6 (standard deviation 12.5) years) hospitalized post-acute stroke. METHODS Functional assessments were made within 3 days of stroke with items from valid and reliable indices commonly utilized to evaluate stroke survivors. Information on important variables was also collected. Principal component and Rasch analysis confirmed the factor structure, and dimensionality of the measure. Rasch analysis combined items across ICF components to develop the measure. Items were deleted iteratively, those retained fit the model and were related to the construct; reliability and validity were assessed. RESULTS A 38-item unidimensional measure of the EPF met all Rasch model requirements. The item difficulty matched the person ability (mean person measure: -0.31; standard error 0.37 logits), reliability of the person-item-hierarchy was excellent at 0.97. Initial validity was adequate. CONCLUSION The 38-item EPF measure was developed. It expands the range of assessment post acute stroke; it covers a broad spectrum of difficulty with good initial psychometric properties that, once revalidated, can assist in planning and evaluating early interventions.

Development of a measure of functioning for stroke recovery: The functional recovery measure

Purpose. To develop a parsimonious measure of functioning for persons after stroke. Method. A sub-set of 206 community-dwelling subjects with a first stroke from a larger cohort was interviewed within 9 months using 39 items from five indices assessing functioning. Information was collected on influencing variables: age, stroke type and severity, and previous health. Two statistical methods, factor analysis and Rasch analysis, confirmed the item structure, hierarchy and dimensionality of the measure. Statistics confirmed fit to the model; internal consistency was also assessed. Items were deleted iteratively based on fit and relationship to the construct. Results. The subjects were predominately male (63%) aged on average 68 years old. A 12-item unidimensional functioning measure was developed. All items and persons fit the Rasch model with stable item – person reliability indices of 0.98 and 0.91, respectively. Item precision (standard errors) ranged from 0.14 – 0.37 logits. Gaps in measurement occurred at the extremes of the measure and there was a small ceiling effect. Conclusions. A 12-item measure captured the concept of functioning that could be used as a prototype to quantify recovery post-stroke. These items could form the basis for a measure of functioning.

Development and initial psychometric evaluation of an item bank created to measure upper extremity function in persons with stroke.

OBJECTIVE To create and illustrate the development of a method to parsimoniously and hierarchically assess upper extremity function in persons after stroke. DESIGN Data were analyzed using Rasch analysis. SETTING Re-analysis of data from 8 studies involving persons after stroke. SUBJECTS Over 4000 patients with stroke who participated in various studies in Montreal and elsewhere in Canada. METHODS Data comprised 17 tests or indices of upper extremity function and health-related quality of life, for a total of 99 items related to upper extremity function. Tests and indices included, among others, the Box and Block Test, the Nine-Hole Peg Test and the Stroke Impact Scale. Data were collected at various times post-stroke from 3 days to 1 year. RESULTS Once the data fit the model, a bank of items measuring upper extremity function with persons and items organized hierarchically by difficulty and ability in log units was produced. CONCLUSION This bank forms the basis for eventual computer adaptive testing. The calibration of the items should be tested further psychometrically, as should the interpretation of the metric arising from using the item calibration to measure the upper extremity of individuals.

The disutility of restenosis--the impact of repeat percutaneous coronary intervention on quality of life.

BACKGROUND Percutaneous coronary intervention (PCI) with coronary stenting is a common medical procedure that is used to treat the symptoms of both stable angina and acute coronary syndromes. Drugeluting stents (DES) decrease restenosis and repeat revascularization procedures but are more expensive than bare-metal stents. A proper cost-effectiveness analysis of DES requires an understanding of the health value patients place on the avoidance of restenosis accompanied by a repeat PCI. OBJECTIVE To estimate quality-of-life (QoL) benefits ascribed to avoiding the return of coronary symptoms and the need for a repeat revascularization procedure. METHODS A prospective, single-centre study was conducted involving PCI patients. A time trade-off (TTO) question, based on a hypothetical restricted lifespan of 10 years, was used to estimate the QoL benefits patients attach to the avoidance of recurrent symptoms and a repeat PCI. This was accomplished by interviewing the patients by telephone, two weeks post-PCI. The TTO question was also administered to the catheterization laboratory staff. RESULTS Between January and March 2007, and between April and June 2008, 103 interviews were completed. The median TTO was zero weeks (interquartile range zero to 1.7 weeks). Six interventional cardiologists and eight cardiac catheterization nurses reported a similar median disutility. CONCLUSION Despite acknowledgement of the substantial clinical benefits of DES, the results of the present study suggest that patients do not place a great disutility on avoiding restenosis, thereby providing little QoL justification for the large incremental cost associated with this technology.

How have research questions and methods used in clinical trials published in Clinical Rehabilitation changed over the last 30 years

Research in rehabilitation has grown from a rare phenomenon to a mature science and clinical trials are now common. The purpose of this study is to estimate the extent to which questions posed and methods applied in clinical trials published in Clinical Rehabilitation have evolved over three decades with respect to accepted standards of scientific rigour. Studies were identified by journal, database, and hand searching for the years 1986 to 2016. A total of 390 articles whose titles suggested a clinical trial of an intervention, with or without randomization to form groups, were reviewed. Questions often still focused on methods to be used (57%) rather than what knowledge was to be gained. Less than half (43%) of the studies delineated between primary and secondary outcomes; multiple outcomes were common; and sample sizes were relatively small (mean 83, range 5 to 3312). Blinding of assessors was common (72%); blinding of study subjects was rare (19%). In less than one-third of studies was intention-to-treat analysis done correctly; power was reported in 43%. There is evidence of publication bias as 83% of studies reported either a between-group or a within-group effect. Over time, there was an increase in the use of parameter estimation rather than hypothesis testing and there was evidence that methodological rigour improved. Rehabilitation trialists are answering important questions about their interventions. Outcomes need to be more patient-centred and a measurement framework needs to be explicit. More advanced statistical methods are needed as interventions are complex. Suggestions for moving forward over the next decades are given.