Paget's disease of bone: the skeletal distribution, complications and quality of life as perceived by patients.

CONTEXT: Paget's disease of bone (PDB) is a focal disorder of bone metabolism with overgrowth of affected bone resulting in the skeletal complications of this disease. OBJECTIVE: This study examines what patients know about the skeletal distribution of their PDB, and correlates this with their reports of complications and quality of life. DESIGN: The New England Registry for PDB (NRPD) is a voluntary registry with a questionnaire linked to a radiographic database. Data were collected by mail beginning in 2001. SETTING: Ambulatory population. PATIENTS: Any patient with PDB living in New England was eligible to enroll; 285 elected to participate, mean age 73.2 years. MAIN OUTCOME MEASURES: Patients were asked what bones were affected by PDB, and whether they suffered complications from PDB. Radiographic studies were sought to corroborate their responses. An SF-12 was administered. RESULTS: Compared to the general population, they reported substantially lower levels of physical health (Physical Component Score (PCS) mean=40), and slightly better mental health (Mental Component Score (MCS) mean=52). There were more instances of agreement on disease presence and fewer instances on disagreement (p=0.001). Radiographic studies supported the presence of a complication from PDB when deformity, fracture and joint replacement had occurred, but were less correlative when headache or hearing loss was reported. CONCLUSIONS: Most patients with PDB are aware of the skeletal distribution of their disease; there is a reasonable correlate between complications ascribed to PDB and the presence of PDB on the radiograph except when headache or hearing loss is reported.

Analysis of patient and proxy ratings on the Dysexecutive Questionnaire: an application of Rasch analysis.

BACKGROUND: We provide an alternate method of analysing self-report and proxy-report data on subjective complaints of dysexecutive symptoms among a group of patients with traumatic brain injury. OBJECTIVE: The purpose of this study was to examine differences in the ratings of patients and proxies on a measure of the dysexecutive syndrome and further explore the insight impairment problem in patients with traumatic brain injury. METHODS: Rasch analysis was conducted on the ratings of the Dysexecutive Questionnaire (DEX) by a sample of patients and their proxies. RESULTS: While the average scores based on patient and proxy ratings were approximately the same (mean patient raw score = 30.12 and mean proxy raw score = 31.32), differential item functioning was found in five DEX items. As a result, the relationship between measures obtained from patient and proxy ratings was only in the moderate range (intraclass correlation = 0.46). CONCLUSIONS: Identification of differential item functioning in five of the 20 DEX items reflected the different perspectives of patients and their proxies in reporting the frequency of dysexecutive behaviour and suggests that these ratings are not interchangeable.

Equating EORTC QLQ-C30 and FACT-G scores and its use in oncological research.

OBJECTIVE: To investigate the equivalence of the European Organization for Research and Treatment of Cancer Core Questionnaire (EORTC QLQ-C30) and the Functional Assessment for Cancer Therapy-General (FACT-G) on the basis of corresponding subscales, and where appropriate to derive a scheme for converting QLQ-C30 scores into FACT-G scores and vice versa for use in oncological research. METHOD: A calibration sample of 737 cancer patients (mean age 51.4+/-7.6 (SD), 63% female, 25% with current chemotherapy) who filled in both quality of life (QOL) questionnaires was used. Both classical test theory and the Rasch measurement model were applied. RESULTS: Three of the four subscales common to both QOL instruments (physical, emotional, functional) proved suitable for equating (acceptable inter-correlations of corresponding subscales physical (r=0.77), emotional domain (r=0.60) role/functional (r=0.63) relative to their internal consistency, sufficient unidimensionality of pooled subscales, satisfactory fit to the Rasch model). Conversion tables for these subscales were generated. CONCLUSIONS: The conversion tables developed in this study (physical, emotional and functional/role domain) appear promising for the comparison between EORTC QLQ-C30 and FACT-G scores of patient samples.

Stroke Impact Scale-16: A brief assessment of physical function.

OBJECTIVES: To 1) develop a short instrument (Stroke Impact Scale-16 [SIS-16]) to assess physical function in patients with stroke at approximately 1 to 3 months poststroke using items from the composite physical domain of the Stroke Impact Scale (SIS) version 3.0, and 2) compare the SIS-16 and a commonly used disability measure, the Barthel Index (BI), in terms of their ability to discriminate disability. METHODS: A total of 621 subjects enrolled in the GAIN Americas randomized stroke trial were included in this study. Rasch analysis, which models the probability of a subject's response to an item using both subject ability and item difficulty, was used to construct the SIS-16, describe its properties, and compare its ordering and range of item difficulties to those of the BI. Box plots and analysis of variance were used to examine differences in BI and SIS-16 scores across modified Rankin categories. RESULTS: The study sample had an average age of 68 +/- 12.4 years and 56% were men. Stroke diagnoses were classified as minor in 91 patients (NIH Stroke Scale score [NIHSS] 0 to 5), moderate in 304 (NIHSS 6 to 13), and major in 226 (NIHSS >/= 14). Twelve of the original 28 items in the SIS version 3.0 composite physical domain were eliminated to produce the SIS-16, with a minimal loss of reliability. As compared to the BI, the SIS-16 contains more difficult items that can differentiate patients with less severe limitations, and therefore has less pronounced ceiling effects. SIS-16 scores were significantly different across Rankin levels 0 to 1, 2, 3, 4, and 5, whereas BI was significantly different only across Rankin levels 0 to 2, 3, 4, and 5. CONCLUSION: Compared to the BI, the SIS-16 is an excellent collection of items suitable for assessing a wide range of physical function limitations of patients with stroke at 1 to 3 months poststroke. Because of a less pronounced ceiling effect, the SIS-16 can differentiate lower levels of disability as compared to the BI.

Development and measurement properties of the Orthotics and Prosthetics Users' Survey (OPUS): a comprehensive set of clinical outcome instruments.

The need to measure and evaluate orthotics and prosthetics (O&P) practice has received growing recognition in the past several years. Reliable and valid self-report instruments are needed that can help facilities evaluate patient outcomes. The objective of this project was to develop a set of self-report instruments that assess functional status, quality of life, and satisfaction with devices and services that can be used in an orthotics and prosthetics clinic. Selecting items from a variety of existing instruments, the authors developed and revised four instruments that differentiate patients with varying levels of lower limb function, quality of life, and satisfaction with devices and services. Evidence of construct validity is provided by hierarchies of item difficulty that are consistent with clinical experience. For example, with the lower limb function instrument, running one block was much more difficult than walking indoors. The instruments demonstrate adequate internal consistency (0.88 for lower limb function, 0.88 for quality of life, 0.74 for service satisfaction, 0.78 for device satisfaction). The next steps in their research programme are to evaluate sensitivity and construct validity. The Orthotics and Prosthetics Users' Survey (OPUS) is a promising self-report instrument which may, with further development, allow orthotic and prosthetic practitioners to evaluate the quality and effectiveness of their services as required by accreditation standards such as those of the American Board for Certification in Orthotics and Prosthetics that mandate quality assessment.

Outcomes of cardiopulmonary arrest in an acute rehabilitation setting.

OBJECTIVE: Fifty consecutive cases of cardiopulmonary arrest with administration of cardiopulmonary resuscitation (CPR) during a 6-yr period at a freestanding academic acute rehabilitation hospital were identified. DESIGN: Medical records of 49 patients were available for review. Outcomes of survival of arrest, survival to 24 hr postarrest, survival to discharge from the hospital were determined, and chi2 or Fisher's exact tests were performed to investigate relationships between survival and admission functional status, age, gender, and medical comorbidities. RESULTS: Forty-three percent of patients survived the initial arrest, 37% survived to 24 hr post-CPR, and 18% survived to hospital discharge. We were unable to identify any statistically significant predictors of survival post-CPR. Six of the nine survivors returned to the acute rehabilitation setting after cardiopulmonary arrest, and five of these patients made significant functional gains. CONCLUSIONS: Outcomes after CPR in patients undergoing acute rehabilitation in one setting were not significantly different from those reported for patients in other healthcare settings. These data may be used by healthcare professionals to enhance discussions concerning advance healthcare planning (including resuscitation plans) with patients and families. Larger studies are needed to clarify the prognostic role of prior functional status in predicting CPR outcomes, particularly in the context of various diagnostic categories and age groups.

Partial credit model and pivot anchoring.

This article contains information on the Rasch measurement partial credit model: what it is, how it differs from other Rasch models, when to use it, and how to use it. The calibration of instruments with increasingly complex items is described, starting with dichotomous items and moving on to polychotomous items using a single rating scale, and mixed polychotomous items using multiple rating scales, and instruments in which each item has its own rating scale. It also introduces a procedure for aligning rating scale categories to be used when more than one rating scale is used in a single instrument. Pivot anchoring is defined and an illustration of its use with the mental health scale of the SF-36 that contains positive and negative worded items is provided. It finally describes the effect of pivot anchoring on step calibrations, the item hierarchy, and person measures.

Measurement properties of the Galveston Orientation and Amnesia Test (GOAT) and improvement patterns during inpatient rehabilitation.

OBJECTIVES: To determine the measurement properties of the Galveston Orientation and Amnesia Test (GOAT) using the Rasch model and rating scale analysis (RSA). DESIGN: Calibration of data collected weekly during rehabilitation. SETTING: Six inpatient rehabilitation facilities. PARTICIPANTS: 77 patients admitted for their first rehabilitation after traumatic brain injury. RESULTS: Rescoring the items as dichotomies, three strata of posttraumatic amnesia (PTA) were identified. All items cohered to define a single construct and the item hierarchy confirmed their hypothesized ordering. CONCLUSIONS: Equal-interval measures of PTA were developed that exhibited good reliability and validity. A self-scoring key was developed to more efficiently assess PTA.

Rating scale analysis of the Agitated Behavior Scale.

OBJECTIVE: Evaluate the measurement properties of the Agitated Behavior Scale (ABS) using rating scale analysis. SAMPLES: Sample 1: 900 observations of 100 individuals with traumatic brain injury; Sample 2: 204 observations of 102 persons with dementia; Sample 3: 241 observations of 6 individuals with anoxia. RESULTS: The calibration indicated that the rating scale was used as intended. The hierarchies of item difficulty were similar across samples. Person and item separation values were within the acceptable range for the TBI sample. Generally, the items work well together, however 3 items misfit the measurement model moderately. CONCLUSIONS: Agitation as measured by the ABS is best represented as a unitary construct. Results provide additional support for the reliability and validity of the ABS.

Rating scale analysis of the Neurobehavioral Cognitive Status Examination.

OBJECTIVE: Evaluate the measurement properties of the Neurobehavioral Cognitive Status Examination (NCSE) using rating scale analysis. DESIGN: Calibration of item responses collected as part of a study examining characteristics of case-management programs and treatment outcomes. SETTING: Three outpatient rehabilitation facilities. PARTICIPANTS: Convenience sample of 186 community-dwelling adults with TBI. RESULTS: Several rating scale analyses were performed to construct a unidimensional measure. Deletion of easy and misfitting items created a better targeted test (generated more spread among individuals) without increased error. CONCLUSIONS: If used with a community-based sample, three strata can be differentiated despite a skewed distribution. Recommended applications are with samples with considerably more cognitive impairment.

Relationship between cognitive impairments and rated activity restrictions in stroke patients.

OBJECTIVE: To investigate the relationship between cognitive impairments and rated activity restrictions. DESIGN: Comparison of neuropsychological tests and activity questionnaires. Activity ratings were made by staff and stroke patients. SETTING: Two neurological rehabilitation hospitals. PARTICIPANTS: Eighty-seven stroke patients. RESULTS: Moderately high correlations were found between cognitive test scores and activity ratings made by staff members. In contrast, correlations between ratings made by patients and cognitive tests were much lower. There was also little agreement between the staffs' ratings and the patients' own ratings. Multiple regression analyses indicate that cognitive impairments account for 28.9% of the variance in the activity rating made by the staff members. The coefficient of determination was slightly higher when age, time since onset of illness, and depression scores were included as predictors. CONCLUSIONS: These findings provide partial support for a hierarchical structure of the "International Classification of Impairment, Activities and Participation" model of the World Health Organization.

Measuring the impairment consequences of spinal cord injury.

The objectives of this study were to develop and validate an equal-interval measure of neurologic impairment from the International Standards for Neurological and Functional Classification of Spinal Cord Injury Patients developed by the American Spinal Injury Association. These standards were used to rate impairment at admission and discharge to Model System facilities. The results demonstrate that the standards fulfill their purpose of characterizing sensory-motor impairment. Developed was a self-scoring key that rehabilitation clinicians can use to obtain a measure of severity that combines sensory and motor level ratings and completeness classifications to describe impairment more precisely and illustrate the magnitude of reductions in impairment. This measure can be used to monitor improvement over time and compare severity across individuals or groups.

A retrospective review of the incidence and rehabilitation outcome of concomitant traumatic brain injury and ligamentous knee injury.

OBJECTIVES: To estimate the incidence of ligamentous knee injuries in patients with traumatic brain injury (TBI) involved in pedestrian versus motor vehicle collisions (PVMVC), to identify associated risk factors, and to compare rehabilitation outcomes and costs in TBI patients with and without ligamentous knee injury. DESIGN: Retrospective, case control. SETTING: An academic rehabilitation hospital with a large metropolitan referral base. PATIENTS: Twenty-three consecutive adolescent and adult subjects admitted for acute inpatient rehabilitation after a PVMVC from January 1, 1994, to January 1, 1996. RESULTS: Five subjects (22%) were found to have a ligamentous knee injury, one with bilateral injuries. Two of these six injuries were diagnosed only after presentation to the rehabilitation setting. The most common injury was an anterior cruciate ligament (ACL) disruption in 5 of 6 knees. A coupled ACL and medial collateral ligament injury was identified in 4 of 6 injured knees. The risk of ligamentous knee injury was most closely associated with the presence of a tibial plateau fracture (n=3) (chi2=12.420, p < .001). There was no statistical difference between groups with and without ligamentous knee injuries with respect to age, gender, inpatient acute or rehabilitation length of stay, admission, discharge, or change in motor Functional Independence Measure (FIM) interval measures, or rehabilitation costs. Four of the 5 patients with ligamentous knee injuries were successfully managed nonoperatively. A case illustrating longitudinal management is presented. CONCLUSIONS: TBI and ligamentous knee injuries, in particular ACL injuries, are common comorbidities after PVMVC. Physicians must maintain a high index of suspicion for ligamentous knee injuries in this population, particularly when a tibial plateau fracture is present. TBI patients with and without ligamentous knee injuries can have comparable functional outcomes when the ligament injuries are identified and appropriately managed, without incurring undue cost or length of inpatient rehabilitation.