Transitions in mobility, ADLs, and IADLs among working-age Medicare beneficiaries.

BACKGROUND: Disability is a dynamic process where functional status may change over time. Examination of the Medicare population suggests that, for those over age 65, disability status will fluctuate in 30% of beneficiaries each year. Less is known about those under age 65. The dynamic nature of disability is of relevance since it has important implications for social policies related to disability. OBJECTIVES: To: (1) describe the characteristics of Medicare beneficiaries eligible due to disability; and (2) estimate the proportion of individuals with transitions in functional status over a one-year period stratified by baseline characteristics and diagnostic subgroups. METHODS: We used the Medicare Current Beneficiary Survey from 1995 to 2005 to examine transitions in mobility and daily activities among individuals who were eligible for Medicare coverage due to disability. RESULTS: From the standpoint of function in mobility and daily activities, the working-age Medicare population with disability is fairly stable. While 75%-90% of our sample reported no disability or stable disability from one year to the next, depending on the condition and disability metric, as many as 13-14% of individuals showed improvement or decline in their functional status. CONCLUSIONS: In the working-age population with disability, a small percentage of individuals will improve or worsen from one year to the next. Since these transitions are associated with a variety of individual characteristics including health conditions, further research applied to larger samples is required to refine policy relevant models that might inform decisions related to ongoing eligibility for disability programs.

Assessment of the health status in Brazilian burn victims five to seven months after hospital discharge.

PURPOSE: To evaluate health status, impact of event, anxiety, and depression in burn victims at five-to-seven months after hospital discharge, and to explore the association between those variables with age, body surface area burn (BSA), sex, and marital status. METHODS: Cross-sectional study involving 73 adults who were interviewed for general health status (BSHS-R), impact of event (IES), and anxiety and depression (HADS). RESULTS: Participants were mostly men (68.5%), with mean age 38.4 years (SD = 14.5), and mean hospital length of stay (LOS) 24.5 days (SD = 25.3). Mean scores were: 128.1 (SD = 18.9) for BSHS-R, 62.1(SD = 35.8) for IES, 5.5 (SD = 4.1) for anxiety, and 3.9 (SD = 3.9) for depression. Health status was highly and inversely correlated with impact of event, depression, anxiety, LOS, number of surgeries, and BSA. Men and women differed in the BSHS-R affect and body image domains, and depression. Individuals with larger BSA reported worse scores for BSHS-R (work domain). CONCLUSION: Burn victims reported good health status on average, which was negatively correlated with reported depression, anxiety, impact of event, LOS, number of operations, and BSA. These findings suggest that general health might be improved by interventions that target modifiable behavioral factors, such as support groups and cognitive behavioral therapies.

Endoscopic assessment of vocal fold movements during cough.

OBJECTIVES: Little is known about the function of the true vocal folds (TVFs) during cough. The objective of this study was to determine the reliability of measuring TVF movements during cough and to obtain preliminary normative data for these measures. METHODS: Sequential glottal angles associated with TVF adduction and abduction across the phases of cough were analyzed from laryngeal videoendoscopy records of 38 young healthy individuals. RESULTS: The intraobserver and interobserver reliability of 3 experienced measurers was high (intraclass correlation of at least 0.97) for measuring sequential and maximum glottal angles. The TVF abduction velocity during expulsion was significantly higher than the precompression adduction velocity (p = 0.002), but there were no significant differences in maximum angle. No statistically significant differences were seen in maximum TVF angle and velocity when they were compared between the sexes and between the levels of cough strength. True vocal fold closure following expulsion occurred in 42% of soft coughs and in 57% of moderate to hard coughs. CONCLUSIONS: The TVF abduction angles during cough can be reliably measured from laryngeal videoendoscopy in young healthy individuals. The TVF movements are faster for expulsion abduction than for precompression adduction, but the extents of abduction are similar. To validly determine the cough phase duration, simultaneous measures of airflow are needed.

Objective Assessment of Joint Stiffness: A Clinically Oriented Hardware and Software Device with an Application to the Shoulder Joint.

Examination of articular joints is largely based on subjective assessment of the "end-feel" of the joint in response to manually applied forces at different joint orientations. This technical report aims to describe the development of an objective method to examine joints in general, with specific application to the shoulder, and suitable for clinical use. We adapted existing hardware and developed laptop-based software to objectively record the force/displacement behavior of the glenohumeral joint during three common manual joint examination tests with the arm in six positions. An electromagnetic tracking system recorded three-dimensional positions of sensors attached to a clinician examiner and a patient. A hand-held force transducer recorded manually applied translational forces. The force and joint displacement were time-synchronized and the joint stiffness was calculated as a quantitative representation of the joint "end-feel." A methodology and specific system checks were developed to enhance clinical testing reproducibility and precision. The device and testing protocol were tested on 31 subjects (15 with healthy shoulders, and 16 with a variety of shoulder impairments). Results describe the stiffness responses, and demonstrate the feasibility of using the device and methods in clinical settings.

Participation in community walking following stroke: subjective versus objective measures and the impact of personal factors.

BACKGROUND: Mobility, specifically community walking, is important, but often limited among survivors of stroke. The factors that influence the recovery of community walking are not clearly understood. OBJECTIVE: The purpose of this research was to examine mobility disability following stroke, specifically: (1) the association between subjective and objective measures of participation in community walking and (2) the association between personal factors and participation in community walking. DESIGN: A cross-sectional study design was used. METHODS: Fifty community-dwelling survivors of stroke, aged 50 to 79 years, were enrolled in the study. Participation in community walking was measured subjectively (perceived difficulty and satisfaction) and objectively using self-report data (number of trips and walking-related activities) and step data (pedometer). The association between subjective and objective measures of participation was analyzed using Pearson correlation. The association of personal factors (age, sex, number of comorbidities, fatigue, depression, balance and fall self-efficacy, and importance of walking) with measures of participation was analyzed using multiple linear regression. RESULTS: Subjective and objective measures of participation were weakly associated. Self-efficacy was the only personal factor that was strongly associated with both subjective and objective measures of participation. Personal factors explained 27% to 55% of the variability in participation in community walking. LIMITATIONS: Limitations included a small sample size and limited diversity among participants. Reliability of the pedometer used in this study has not been established in the stroke population. CONCLUSIONS: Subjective and objective measures of participation in community walking were only weakly correlated, suggesting that they measure different aspects of mobility; thus, to fully capture participation, it is critical to measure both. Personal factors were associated with subjective and objective measures of participation and are important in explaining variability in community walking following stroke.

Central fabrication: carved positive assessment.

BACKGROUND: It is estimated that only 24% of practitioners use CAD/CAM regularly. Socket manufacturing error may be a source of the limited use of central fabrication. OBJECTIVES: The purpose of this study was to investigate the differences in shape between computer-manufactured, centrally fabricated carved models and electronic file shapes, to determine if carving was a major source of socket manufacturing error in central fabrication. STUDY DESIGN: Experimental, mechanical assessment. METHODS: Three different trans-tibial model shapes were sent electronically to each of 10 central fabrication facilities for the fabrication of positive foam models. A custom mechanical digitizer and alignment algorithm were used to measure the model shapes and then compare them with the electronic file shapes. RESULTS: Volume differences between the models and the electronic file shapes ranged from -4.2% to 1.0%, and averaged -0.9 (SD = 1.1)%. Mean radial error ranged from -1.2 mm to 0.3 mm and averaged -0.3 (SD = 0.3) mm. Inter-quartile range was between 0.3 mm and 2.7 mm and averaged 0.6 (SD = 0.5) mm. The models were significantly smaller than sockets made from the same electronic file shapes (p < 0.01), but the range of mean radial error and the interquartile range were not significantly different between the models and sockets. CONCLUSIONS: The results demonstrated that there was considerable variability in model quality among central fabricators in the industry, and that carving was not the sole source of socket fabrication error. CLINICAL RELEVANCE: The results provide insight into the severity and nature of carving error by central fabrication facilities. Because we found a wide range of model quality, there is not a consistent fabrication problem across the industry, but instead some central fabrication facilities practice the art of model fabrication better than others.

Delayed or forgone care and dissatisfaction with care for children with special health care needs: the role of perceived cultural competency of health care providers.

To better understand if reported delayed/forgone care and dissatisfaction with care for children with special health care needs (CSHCN) are associated with the parent's perception of health care providers' cultural competency. National survey. Fifty United States and the District of Columbia yielding 750 families per state and District of Columbia with CSHCN ≤ 18 years participated in the 2005-06 National Survey of CSHCN. Outcome measures were delayed/forgone care in the past 12 months (yes or no) and dissatisfaction (very dissatisfied to very satisfied). Demographic/clinical characteristics and the parent's perception of health care providers' cultural competency were examined. Perception of cultural competency was defined by questions related to time spent with child, respect for family values, listening to the family, sense of partnership, and information provided. Delayed/forgone care and dissatisfaction with care were associated with perceived health care provider cultural competency. Parents whose children were older, whose children's condition affected their ability to do things, whose interviews were not conducted in English, and were from certain racial and ethnic groups reported more delayed or forgone care and were more dissatisfied with their children's health care. Delayed/forgone care and dissatisfaction with care were associated with perceived cultural competency of health care providers. This did not appear to differ consistently by racial or ethnic group. Further research using more refined instruments and longitudinal designs is needed to assess the effects of health care providers' cultural competency and other cultural factors on the delayed/forgone care for CSHCN and on the dissatisfaction with care of parents with CSHCN.

Understanding physical factors associated with participation in community ambulation following stroke.

PURPOSE: This study examined the association between impaired physical function and participation in community ambulation following stroke. We hypothesised that participation would be significantly less following stroke, and that physical impairments would be associated with participation. METHOD: Using a case-control design 30 survivors of stroke aged 45 and older and 30 controls provided health status information and a self-report of participation in community ambulation (number of trips and walking-related activities (WRA) reported prospectively over a 12-day period). The association of physical impairments (strength, range of motion, sensation, muscle tone, vision, and activity limitations (gait speed and performance on complex walking tasks)) with level of participation was analysed using negative binomial regression and goodness of fit. RESULTS: Participants included 30 individuals with and 30 without stroke, average age 68 years, majority were Caucasian women. Average time since stroke was 40 months. Participation in survivors of stroke was characterised by fewer trips and WRA and lower satisfaction (p < 0.001). Usual gait speed, balance, muscle strength and muscle length were impaired (p < 0.001) in stroke vs. controls, and associated with number of trips and WRA (p < 0.05). However, these factors explained less than very little of the variance in participation. CONCLUSIONS: While individual factors were associated with level of participation, results failed to accurately predict participation in community ambulation following stroke. Other factors, such as depression, cognition and self-efficacy may be stronger determinants of participation.

Estimating transition probabilities in mobility and total costs for medicare beneficiaries.

OBJECTIVE: To examine how persons move back and forth along levels of mobility disability. DESIGN: Self-reported mobility limitations were used to create categories of annual transition states. The total cost to Medicare associated with each year was calculated for each participant. In addition, we examined cost relative to transition state, adjusting for demographic and other health status variables. SETTING: National survey. PARTICIPANTS: Participants in the longitudinal Medicare Current Beneficiary Survey from 1992 to 2005. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Annual self-reported mobility limitations and total Medi costs. RESULTS: Most participants remained without mobility limitations or improved over time. Reported average costs were 10 times higher for those who transitioned to severe limitations, unable to walk, or death compared with persons who reported no mobility limitation. Estimated costs were highest for those transitioning to increased states of disability and to death. CONCLUSIONS: Mobility limitations in older adults are dynamic, and improvement (as measured by annual transitions) occurred for a large number of Medicare beneficiaries. High total annual costs were observed in groups that transitioned to worsening mobility states, suggesting a link between mobility limitation transitions and cost. Prevention and treatment of mobility limitation may be an important factor to consider in health care reform.

A longitudinal analysis of total 3-year healthcare costs for older adults who experience a fall requiring medical care.

OBJECTIVES: To compare longitudinal changes in healthcare costs between fallers admitted to the hospital at the time of the fall (admitted), those not admitted to the hospital (nonadmitted), and nonfaller controls; test hypotheses related to differences in mean costs between and within these groups over time; and estimate the costs attributable to falling. DESIGN: Longitudinal cohort. SETTING: Group Health Cooperative of Puget Sound. PARTICIPANTS: Seven thousand nine hundred ninety-three nonadmitted fallers, 976 admitted fallers, and 8,956 nonfallers aged 67 and older enrolled in an integrated healthcare delivery system. Fallers were identified according to fall-related E-Codes and International Classification of Diseases, Ninth Revision codes recorded between January 1, 2004, and December 31, 2006. Nonfallers were frequency matched on age group and sex. MEASUREMENTS: Quarterly costs during a 3-year period were modeled using generalized estimating equations. Covariates included index age, sex, RxRisk (a comorbidity adjuster), fall status, time, and interactions between fall status and time. RESULTS: Cost differences between the faller cohorts and nonfallers were greatest in quarters closest to the fall (all P<.01) and persisted throughout the entire year of follow-up. Although nonfaller costs increased with time, faller cohort costs increased more quickly (all P<.01). For admitted fallers, 92% of costs incurred in the quarter of the fall were estimated to be attributable to falling ($27,745 of $30,038, P<.001). CONCLUSION: Falls for which medical attention are sought resulted in higher costs than for nonfallers for up to 12 months after a fall, particularly for falls requiring hospitalization. Prevention efforts should focus on reducing fall-related injuries requiring hospitalization because they produce the highest excess costs and have a higher likelihood of 1-year mortality.

Disparities in outpatient and home health service utilization following stroke: results of a 9-year cohort study in Northern California.

OBJECTIVE: To examine whether there are disparities in utilization of outpatient and home care services after stroke. DESIGN: Retrospective cohort study. SETTING: The Kaiser Permanente of Northern California health care system, which provides health care for approximately 3.3 million members. PARTICIPANTS: A total of 11,119 patients hospitalized for a stroke between 1996 and 2003 and followed for 1 year. MAIN OUTCOME MEASURES: Receipt of outpatient rehabilitation (physical therapy, occupational therapy, speech pathology, or physical medicine and rehabilitation/physiatry visits), and/or home health care. RESULTS: There were significant differences in outpatient rehabilitation visits and home health enrollment during the year after acute care discharge for all the parameters under study. Older age and female gender were associated with less outpatient rehabilitation treatment, but these subpopulations were more likely to be enrolled in home health care. Non-whites, patients from urban areas, those with ischemic strokes, and those with longer acute care hospital stays had relatively more outpatient rehabilitation and were also more likely to be enrolled in the home health program. In addition, patients living in geographic areas with a median household income of $80,000 or more had significantly more outpatient rehabilitation visits than did patients living in lower income areas. CONCLUSIONS: Variations in outpatient rehabilitation visits and in home health care exist in this large integrated health system in terms of age, gender, race/ethnicity, residence area, type of stroke, and length of stay in an acute care hospital. The Kaiser Permanente integrated health care system seems to have outpatient stroke rehabilitation and home health programs that are providing care without disparities in relation to non-white populations, but other disparities appear to exist that may be related to socioeconomic factors, referral patterns, family support systems, or other cultural factors that have not been identified.

Disparities in stroke rehabilitation: results of a study in an integrated health system in northern California.

OBJECTIVE: To determine whether there are disparities in postacute stroke rehabilitation based on type of stroke, race/ethnicity, sex/gender, age, socioeconomic status, geographic region, or service area referral patterns in a large integrated health system with multiple levels of care. DESIGN: Cohort study tracking rehabilitation services for 365 days after acute hospitalization for a first stroke. SETTING: The Northern California Kaiser Permanente Health System (approximately 3.3 million membership population) PARTICIPANTS: A total of 11,119 patients hospitalized for acute stroke from 1996 to 2003. The cohort includes patients discharged from acute care after a stroke. Postacute care rehabilitation services were evaluated according to the level of care ever-received within the 365 days after discharge from acute care, including inpatient rehabilitation hospital (IRH), skilled nursing facility (SNF), home health and outpatient, or no rehabilitation services. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE: Service delivery. RESULTS: Patients discharged to an IRH had longer lengths of stay in acute care. Patients with hemorrhagic stroke were less likely to be treated in an IRH. Patients whose highest level of rehabilitation was SNF were older and more likely to be women. After adjusting for age and other covariates, women were less likely to go to an IRH than men. Asian and black patients were more likely than white patients to be treated in an IRH or SNF. Also more likely to go to an IRH were patients from higher socioeconomic groups, from urban areas, and from geographic areas close to the regional rehabilitation hospital. CONCLUSIONS: These results suggest variation in care delivery and extent of postacute care based on differences in patient demographics and geographic factors. Results also varied over time. Some minority populations in this cohort appeared to be more likely to receive IRH care, possibly because of disease severity, family support systems, cultural factors, or differences in referral patterns.

Falls in the Medicare population: incidence, associated factors, and impact on health care.

BACKGROUND AND PURPOSE: Falls are a major health problem in the elderly community; however, questions regarding incidence, risk factors, and provider response to falls exist. The purpose of this study was to examine the incidence of falls, associated factors, health care costs, and provider response to falls among Medicare beneficiaries. PARTICIPANTS: The participants were 12,669 respondents to the Medicare Current Beneficiaries Survey (MCBS). METHODS: Categories of number of falls (none, one, recurrent) and injury type (medically injurious versus not medically injurious) were created from the falls supplement to the MCBS. Means and proportions for the entire Medicare population were estimated using sampling weights. The association between sociodemographic variables and fall status was modeled using ordinal or binary logistic regression. Aggregate health costs by fall category were estimated from claims data. RESULTS: Population estimates of falls reported in 2002 ranged from 3.7 million (single fall) to 3.1 million (recurrent falls), with an estimated 2.2 million people having a medically injurious fall. Recurrent falls were more likely with increased age, being female, being nonwhite, reporting fair or poor health, and increased number of limitations in personal activities of daily living and instrumental activities of daily living and comorbidities. Although estimates of the actual costs of falls could not be determined, "fallers" consistently had larger utilization costs than "nonfallers" for the year 2002. Fewer than half (48%) of the beneficiaries reported talking to a health care provider following a fall, and 60% of those beneficiaries reported receiving fall prevention information. DISCUSSION AND CONCLUSION: Falls are common and may be associated with significant health care costs. Most importantly, health care providers may be missing many opportunities to provide fall prevention information to older people.

Managing activity difficulties at home: a survey of Medicare beneficiaries.

OBJECTIVE: To describe assistance from helpers and use of assistive technology and environmental modification by community-dwelling people with difficulties in activities of daily living (ADLs) and instrumental activities of daily living (IADLs). DESIGN: Cross-sectional study using the 2004 Medicare Current Beneficiary Survey. SETTING: Community. PARTICIPANTS: Nationally representative sample of 14,500 Medicare beneficiaries (mean age, 71.5 y; 55% female; 49% currently married; 68% living with others; 84% white). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Self-reported difficulty with ADLs and IADLs; uses of help, assistive technology, and/or environmental modification. RESULTS: Difficulties were reported most frequently for heavy housework, walking, and shopping; money management, shopping, and light housework were reported as activities most often needing a helper. Walking, bathing, and toileting were activities most often needing uses of assistive technology. Bathroom modifications were the most commonly reported environmental modification. Results from a logistic regression showed that advancing age was the primary factor associated with increasing use of helpers and assistive technology or both for difficult activities. CONCLUSIONS: Uses of helpers, assistive technology, and environmental modification are common but vary by type of ADL and/or IADL and age. Focused studies regarding uses of help and access to assistive technology and environmental modification appear needed to support community living. Public education about methods and types of accommodations appears needed and may substitute for or augment guidance from care providers.

A longitudinal evaluation of persons with disabilities: does a longitudinal definition help define who receives necessary care?

OBJECTIVE: To assess, using a longitudinal definition, the impact of disability on a broad range of objective health care quality indicators. DESIGN: Longitudinal cohort study following up with patients over several years. The first 2 interviews, 1 year apart, were used to determine each patient's disability status in activities of daily living (ADLs). Assessment of the health care indicators commenced after the second interview and continued throughout the survey period (an additional 1-3y). SETTING: National survey. PARTICIPANTS: Participants (N=29,074) of the Medicare Current Beneficiary Survey (1992-2001) with no, increasing, decreasing, and stable ADL disability. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE: The incidence of 5 avoidable outcomes, receipt of 3 preventive care measures, and adherence to 32 diagnostically based indicators assessing the quality of treatment for acute myocardial infarction [AMI], angina, breast cancer, cerebrovascular accident, transient ischemic attack, cholelithiasis, chronic obstructive pulmonary disease [COPD], congestive heart failure, depression, gastrointestinal bleeding, diabetes, and hypertension. RESULTS: For most indicators, less than 75% of eligible patients received necessary care, regardless of disability status. For 5 indicators, less than 50% of patients received appropriate treatment. In a logistic regression analysis that controlled for patient age, sex, race, and income, disability status was a significant factor in 7 quality measures (AMI, breast cancer, COPD, diabetes, angina, pneumonia, annual visits). CONCLUSIONS: Using a longitudinal definition of disability and objective health quality indicators, we found that disability status can be an important factor in determining receipt of quality health care in a broad range of diagnostic categories. However, the impact of disability status varies depending on the indicator measured. In this cohort of patients, the changing nature of a person's disability seems to have less impact than whether they ever have had any functional deficits.

Minority disparities in disability between Medicare beneficiaries.

OBJECTIVES: To examine racial and ethnic disparities in mobility limitation, activities of daily living (ADLs), and instrumental activities of daily living (IADLs) in older adults enrolled in Medicare. DESIGN: Longitudinal national survey. PARTICIPANTS: Community-dwelling respondents in the Medicare Current Beneficiaries Survey from 1992 to 2004 (10,180-16,788 respondents per year). MEASUREMENTS: Disability-related outcomes included mobility limitation, difficulty in six ADLs and six IADLs. Explanatory variables included age, sex, racial or ethnic group, living situation, and income level. RESULTS: From 1992 to 2004, proportions of Medicare beneficiaries with mobility limitations were stable across racial and ethnic groups, improving slightly for ADLs and IADLs. Blacks reported more limitations in all three disability-related measures. In a longitudinal analysis, the probability of developing mobility limitation was consistently higher for blacks, followed by white Hispanics, white non-Hispanics, and Asians, after adjusting for age, sex, socioeconomic status, and living situation. For ADL and IADL difficulties, the number of reported difficulties increased with age for all ethnic and racial groups. At approximately age 75, Asians and white Hispanics reported difficulties with much higher numbers of ADLs and IADLs than the other groups. CONCLUSION: Across all ethnic and racial groups, self-reported disability has declined in the past decade, but even after adjusting for age, sex, socioeconomic status, and living situation, racial and ethnic disparities in disability outcomes persist. Race and ethnicity may influence the reporting of disability, potentially affecting measures of prevalence. Further research is needed to understand whether these differences are a result of perceptions related to disablement or true differences in disability between racial and ethnic groups.

Association of mobility limitations with health care satisfaction and use of preventive care: a survey of Medicare beneficiaries.

OBJECTIVE: To examine the association between satisfaction with health care, the use of preventive health care, and mobility limitation. DESIGN: Cross-sectional analysis of survey data. SETTING: Community. PARTICIPANTS: A total of 12,769 people, age greater than 65, who participated in the 2001 Medicare Current Beneficiary Survey. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Self-report of mobility limitation, satisfaction, and use of preventive health care (immunizations, cancer screening). Sampling weights were used in all analyses, including logistic regression for survey data, to calculate estimates for a Medicare population of 31 million. RESULTS: After controlling for sociodemographic characteristics, Medicare beneficiaries with mobility limitations were significantly more dissatisfied with their health care compared with beneficiaries without mobility limitations. Receipt of preventive care did not differ for those with and without mobility limitation on some preventive services. CONCLUSIONS: Mobility limitation is highly associated with dissatisfaction with health care among older adult beneficiaries. Although Medicare beneficiaries may receive similar rates of preventive care, those with mobility limitation may have more difficulty accessing services and be more dissatisfied with their health care in general.

Understanding the use of weights in the analysis of data from multistage surveys.

Understanding the use of weights in the analysis of data from multistage surveys. Large national surveys are powerful tools with which to examine a variety of important rehabilitation-related issues and are currently the only feasible method to study disability trends over time. Because it is impractical to draw simple random samples from the entire United States, national surveys, such as the Medicare Current Beneficiary Survey (MCBS), select random samples of subgroups of a population. Thus, respondents may have unequal probabilities of being included in the survey, and weighting must be used in the analysis before the results may be generalized to the entire United States. Surveys such as the MCBS are rich sources of data for rehabilitation medicine, and it can be expected that more research will be conducted using these data sources. Statistical analysis of these data should account for the sampling scheme used in data collection. We review the principles involved in the design of multistage samples, the calculation of weights, and their use in the data analysis, focusing on their importance in the estimation of population values. Our objective is to help readers to understand and interpret results of research articles using this methodology. Examples using the MCBS data are provided to clarify the concepts presented in the article.

Effect of communication disability on satisfaction with health care: a survey of medicare beneficiaries.

PURPOSE: To examine the prevalence and characteristics of community-dwelling Medicare beneficiaries reporting a communication disability and the relationship between that disability and dissatisfaction with medical care. METHOD: A total of 12,769 Medicare Current Beneficiary Survey respondents age 65 and older in 2001 were categorized by level of communication disability. Sampling weights were used to make inferences about the entire Medicare population. RESULTS: Over 16 million beneficiaries reported a communication disability. Hearing problems were most commonly reported (41.99%). The association between dissatisfaction and communication disability was statistically significant (p

Mobility limitations in the Medicare population: prevalence and sociodemographic and clinical correlates.

OBJECTIVES: To examine the prevalence of and clinical markers associated with mobility limitations in Medicare Current Beneficiary Community Survey (MCBS) respondents. DESIGN: Cross-sectional analysis of a community survey. SETTING: Community. PARTICIPANTS: Twelve thousand seven hundred sixty-nine respondents from the 2001 MCBS, aged 65 and older. MEASUREMENTS: Four questions from the MCBS were used to create four levels of mobility limitation: none, mild, moderate, and severe. Sampling weights were used to calculate estimates of means and proportions of the entire Medicare population for each mobility limitation category. A polytomous logistic regression analysis was used to model the association between four levels of mobility limitation and sociodemographic and clinical variables. RESULTS: Prevalence of mobility limitations ranged from 9.5 million (mild) to 1.2 million (severe). Increasing severity of mobility limitation was associated with older age, being female, reporting fair or poor health, being overweight, smoking, having a greater number of comorbidities, having an annual income below $25,000, having less than a high school education, being unmarried, and living with others. CONCLUSION: National prevalence estimates suggest that functional mobility limitation is a significant problem for many older adults and is associated with some potentially modifiable characteristics.