Biomedical subjects

Richard N Ross

Publications and source records attributed to Richard N Ross.

6 recordsLinked to original sources

PubMed2006

Variation in chemotherapy utilization in ovarian cancer: the relative contribution of geography.

OBJECTIVE: This study investigates geographic variation in chemotherapy utilization for ovarian cancer in both absolute and relative terms and examines area characteristics associated with this variation. DATA SOURCES: Surveillance, Epidemiology, and End Results (SEER) Medicare data from 1990 to 2001 for Medicare patients over 65 with a diagnosis of ovarian cancer between 1990 and 1999. Chemotherapy within a year of diagnosis was identified by Medicare billing codes. The hospital referral region (HRR) represents the geographic unit of analysis. STUDY DESIGN: A logit model predicting the probability of receiving chemotherapy by each of the 39 HRRs. Control variables included medical characteristics (patient age, stage, year of diagnosis, and comorbidities) and socioeconomic characteristics (race, income, and education). The variation among HRRs was tested by the chi2 statistic, and the relative contribution was measured by the omega statistic. HHR market characteristic are then used to explain HRR-level variation. PRINCIPAL FINDINGS: The average chemotherapy rate was 56.6 percent, with a range by HRR from 33 percent to 67 percent. There were large and significant differences in chemotherapy use between HRRs, reflected by a chi2 for HRR of 146 (df = 38, p < .001). HRR-level variation in chemotherapy use can be partially explained by higher chemotherapy rates in HRRs with a higher percentage of hospitals with oncology services. However, an omega analysis indicates that, by about 15 to one, the variation between patients in use of chemotherapy reflects variations in patient characteristics rather than unexplained variation among HRRs. CONCLUSIONS: While absolute levels of chemotherapy variation between geographic areas are large and statistically significant, this analysis suggests that the role of geography in determining who gets chemotherapy is small relative to individual medical characteristics. Nevertheless, while variation by medical characteristics can be medically justified, the same cannot be said for geographic variation. Our finding that density of oncology hospitals predicts chemotherapy use suggests that provider supply is positively correlated with geographic variation.

Aged↗

PubMed2005

Functional status measures for integrating medical and social care.

PURPOSE: Identify standard self-report questions about functioning suitable for measuring disability across integrated health and social services. THEORY: Functional activities can be validly grouped according to the International Classification of Functioning, Disability and Health (ICF) chapters of mobility, self-care, and domestic life. METHODS: Cross-sectional analysis using information on 112,601 persons interviewed as part of the United States National Health Interview Survey on Disability. We combined related sets of questions and tested the appropriateness of their groupings through confirmatory factor analyses. Construct validity was addressed by seeking to confirm clinically logical relationships between the resulting functional scales and related health concepts, including number of physician contacts, number of bed days, perception of illness, and perception of disability. RESULTS: Internal consistency for the summed scales ranged from 0.78 to 0.92. Correlations between the functional scales and related concepts ranged from 0.12 to 0.52 in directions consistent with expectations. CONCLUSIONS: Analyses supported the 3 ICF chapters. DISCUSSIONS: The routine collection of this core set of functions could enhance decision-making at the client, professional, organizational, and policy levels encouraging cooperation among the medical and social service sectors when caring for people with disabilities.

Journal Article↗

PubMed2004

Estimating health-related quality of life in populations through cross-sectional surveys.

BACKGROUND: Health-related quality of life (HRQL) is optimally reported from the individual vantage point; consequently, prevalence estimates from the National Health Interview Survey (NHIS) could be misleading, because approximately one third of the information is proxy-provided. OBJECTIVE: The objective of this study was to discern the degree to which disparities in the crude prevalence of reduced HRQL is explainable by case-mix differences between proxy- and self-reportees. SUBJECTS: We studied the cross-sectional data on 96,091 persons from the 1994-1995 NHIS Supplement on Disability. RESEARCH DESIGN: We conducted a study of reduced HRQL expressed as a respondent type indicator (proxy vs. self) adjusting for socioeconomic differences and limitations in function. MEASURES: We studied reduced HRQL indicated by 1) perception of poor health, 2) perception of disability, 3) 30 or more bed days in the last year, or 4) 20 or more doctor visits in the last year. RESULTS: The crude estimated prevalence of reduced HRQL for proxy reports was approximately half that of self-reports. Although the unadjusted odds ratios (ORs) for proxy- compared with self-reportees ranged from 0.51 (95% confidence interval [CI], 0.47-0.55) to 0.59 (95% CI, 0.55-0.64), case-mix adjustment resulted in a significant directional change for poor health perception, and all adjusted ORs were substantially closer to 1.0 than their unadjusted counterparts. CONCLUSION: Adjustment for case-mix explained away most of the proxy-/self-report disparity, suggesting that a major component of differences in prevalence between proxy- and self-respondents is case-mix-related. Consequently, compared with excluding proxy reports, inclusion of proxy reports results in relatively less bias when the NHIS-D is applied to obtain prevalence estimates for the indicators studied.

Activities of Daily Living↗

PubMed2003

Staging functional independence validity and applications.

OBJECTIVES: To establish construct and predictive validity of the activities of daily living, sphincter-management, mobility, and executive-function (ASME) staging system of functional independence and to describe potential applications. DESIGN: National data were used to validate the stages. Sensitivity to functional change was addressed by comparing patients' stages at discharge to their stages at admission. Construct validity was assessed by examining stage distribution differences among groups of patients classified by impairment category. Predictive validity was determined by the degree to which high stages at admission predict discharge to the community and low stages at admission predict serious morbidity or mortality. SETTING: Inpatient rehabilitation facilities. PARTICIPANTS: Data from 231,686 individuals discharged from 560 US inpatient rehabilitation facilities in 1995. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Stage at rehabilitation discharge, community discharge, acute hospital discharge, or death while in rehabilitation. RESULTS: More than 90% of patients were discharged at a higher stage in at least 1 domain while not declining in any other domain. The odds (95% confidence interval) of community discharge for patients admitted at the highest compared with the lowest stage varied from 2.1 (1.9-2.2) to 3.1 (2.9-3.2), depending on the domain. The odds of acute hospitalization or death were reduced at the highest stages, compared with the lowest, by a factor ranging from .33 (.22-.49) to .65 (.61-.69). CONCLUSIONS: The ASME stages appear valid and sensitive to change. Functional Independence Staging (FIS) has relevance in establishing prognoses and in selecting among therapeutic modalities. FIS will facilitate the identification of meaningful functional goals and interpretable clinical trial endpoints. One of its most important applications could be in the establishment of outcome indicators for quality monitoring under the prospective payment system.

Activities of Daily Living↗

PubMed2003

Functional independence staging: conceptual foundation, face validity, and empirical derivation.

OBJECTIVE: To develop a staging system for functional independence across the activities of daily living (ADLs), sphincter-management, mobility, and executive-function domains (ASME) for the FIM instrument that is consistent with the International Classification of Functioning, Disability and Health. DESIGN: National data were used to define the stages. We searched for the most likely configurations of item scores that increased ability to perform component activities in each domain by approximately 1 level per item per stage. SETTING: Inpatient rehabilitation facilities. PARTICIPANTS: Data from 218,290 people discharged from 560 US inpatient rehabilitation facilities in 1995. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Activity profiles formed from FIM scores. RESULTS: Seven stages were defined separately for each ASME domain. Stages approximate the average amount of effort expended by the patient when performing the component activities included in a domain, beginning with less than 25% of effort at the lowest total assistance (stage 1) and ending with 100% effort at the highest complete independence (stage 7). Consistent with developmental principles, independence is achieved at lower stages in the most fundamental activities of eating, transfers, and communication. Recovery of independence in the more difficult activities of bathing, stair climbing, and problem solving does not occur until the higher stages are reached. The degree of independence is described with a shorthand abbreviation of the domains followed by the stage the patient has reached in each domain. For example, ASME 5,1,6,7 indicates need for supervision in the ADLs (A-5), total assistance in sphincter management (S-1), modified independence in mobility (M-6), and complete independence in executive functions (E-7). CONCLUSIONS: ASME stages serve as a common language and shorthand for expressing the functional consequences of illness and injury, while complementing information about impairment and diagnosis, thereby facilitating communication, assessment, and goal setting in terms that are meaningful to patients and their care givers.

Activities of Daily Living↗

PubMed2003

Predicting the achievement of 6 grades of physical independence from data routinely collected at admission to rehabilitation.

OBJECTIVE: To develop prognostic indexes with which to establish the likelihood of individuals achieving specific grades of physical independence by the conclusion of inpatient rehabilitation. DESIGN: Logistic regression with prospective validation. SETTING: Five hundred sixty inpatient rehabilitation facilities. PARTICIPANTS: Records of 218,290 adults discharged in 1995 were used to establish the grades and the indexes predicting those grades. There were 259,806 1997 discharges included in the validation. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Six physical independence grades reflecting the most likely profiles of performance across the 13 motor FIM items. RESULTS: After severity adjustment, patients 65 years of age or younger, compared with those 84 years of age or older, had odds ratios of reaching higher grades ranging from 1.5 (95% confidence interval [CI], 1.4-1.7) to 7.5 (95% CI, 4.3-13.1). Admission to rehabilitation within 2 weeks of disability was associated with more favorable prognoses. Areas under the receiver operating characteristic curve ranged from.80 to.94 for the indexes, with minimal shrinkage on prospective validation. CONCLUSION: The models have sufficient reliability to establish from admission information the likelihood that a patient will achieve a specific grade of physical independence by the time of discharge from rehabilitation. The capacity to quantify prognosis has clinical, policy, and research applications.

Activities of Daily Living↗