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PubMed2026

Matching-adjusted indirect comparison of fruquintinib versus ramucirumab in advanced gastric or gastroesophageal junction adenocarcinoma.

Aim: Fruquintinib (Fruq), a selective VEGFR 1/2/3 inhibitor, showed a significant progression-free survival (PFS) benefit in the Phase III FRUTIGA trial for advanced gastric/gastroesophageal junction (G/GEJ) adenocarcinoma. Ramucirumab (RAM), an anti-VEGFR2 antibody, demonstrated efficacy in the RAINBOW-Asia trial. This anchored matching-adjusted indirect comparison (MAIC) evaluated Fruq plus paclitaxel versus RAM plus paclitaxel as second-line therapy for G/GEJ adenocarcinoma in the absence of head-to-head trials. Materials & methods: Data from individual patients in the FRUTIGA study (N = 703) and aggregated data from the RAINBOW-Asia study (N = 440) were analyzed. Baseline characteristics were balanced using entropy balancing. The placebo plus paclitaxel (PBO + PTX) groups served as the common comparators. The primary outcome was PFS; secondary outcomes included overall survival, objective response rate (ORR) and disease control rate (DCR). Rates of treatment-emergent adverse events (TEAEs) were also compared as an exploratory outcome using an adjusted indirect risk difference. Sensitivity analyses included restricted mean survival time and simulated treatment comparison. Results: After weighting (effective sample size = 564), baseline covariates were balanced. The anchored MAIC demonstrated that Fruq + PTX significantly improved PFS compared with RAM + PTX (HR: 0.70; 95% CI: 0.51-0.96; p = 0.0280), corresponding to a 30% reduction in progression risk, with a significant restricted mean survival time benefit of 1.18 months at 20 months (95% CI: 0.08-2.27; p = 0.024). Fruq achieved significantly higher ORR (OR: 1.76, 95% CI: 1.16-2.68; p = 0.008) and DCR (OR: 1.94, 95% CI: 1.33-2.83; p < 0.001). Overall survival was similar (0.97; 95% CI: 0.73-1.30; p = 0.8640). Subgroup analyses showed PFS benefits with Fruq in patients with ECOG PS 1, peritoneal metastases and two or fewer metastatic sites. In sensitivity analysis, the simulated treatment comparison also suggested a PFS benefit for Fruq + PTX (HR: 0.40, 95% CI: 0.32-0.50; p < 0.0001). For any-grade TEAEs, the indirect comparison showed higher adjusted relative incidences of increased bilirubin with Fruq + PTX than with RAM + PTX (RD: 12.3%; 95% CI: 2.3-22.4%, p < 0.05) and of hypokalemia (RD: 9.0%; 95% CI: 1.5-16.4%, p < 0.05). For grade ≥3 TEAEs, the adjusted relative incidence of decreased body weight was higher with Fruq + PTX than with RAM + PTX (RD: 2.9%; 95% CI: 0.6-5.2%, p < 0.05). The adjusted relative incidences of increased AST, ALT and hypocalcemia were numerically lower in the fruquintinib group than in the RAM group. Conclusion: This MAIC indicates that Fruq + PTX may be more effective than RAM + PTX in second-line advanced G/GEJ adenocarcinoma, with potentially improved PFS, ORR and DCR, and similar overall survival. Safety analyses suggested generally comparable safety profiles across the two regimens. Fruq + PTX remains a valuable treatment option, offering important comparative evidence for clinical and health technology assessment decisions. Trial Registration: Clinicaltrials.gov identifiers: NCT07144995.

Adult↗

PubMed2003

Brain activation and the phonological loop: the impact of rehearsal.

Brain activation studies offer valuable techniques for exploring human cognition to complement behavioral measures and several studies report a wide range of neuroanatomical networks activated during verbal immediate memory. Behavioral investigations have shown use of multiple cognitive strategies across and within individuals, although aggregate data appear to reflect a common cognitive function. Variation in cognitive strategies could result in aggregate activation patterns that are relatively widespread and difficult to interpret. Imaging data (fMRI) from six participants instructed to use subvocal rehearsal showed significant left hemisphere activation in the inferior parietal gyrus and inferior and middle frontal gyri, a pattern of activation more clearly focused than in previous brain activation studies of immediate verbal serial ordered recall. Our results should be relatively free of the influence of other mental operations, and emphasise the importance of considering which cognitive strategies might give rise to focused or to diverse patterns of brain activation.

Adult↗

PubMed2005

Detection of anthelmintic resistance: a comparison of mathematical techniques.

Anthelmintic resistance has become an increasing problem particularly to gastrointestinal tract nematodes and appropriate methods are required to detect this phenomenon so the correct action can be taken. This paper compares a number of mathematical techniques that are used to analyse data. The negative binomial distribution is a mathematical distribution used to model aggregated data and hence is suitable to model the intensity of parasite burden and the magnitude of the faecal egg counts. Maximum likelihood techniques are utilised to exploit this mathematical distribution to analyse the magnitude of the faecal egg count reduction and decline in the worm burden in response to anthelmintic treatment. Data from experimental groups of sheep described in the accompanying paper are used. In addition, simulated data sets of faecal egg counts were created using a random number generator following appropriate negative binomial distributions. The results demonstrate this statistical model can detect evidence of anthelmintic resistance with a faecal egg reduction test that otherwise might require a slaughter trial to demonstrate. In addition, the simulated data sets confirm that there is a significant probability of failure to detect low anthelmintic efficacy with commonly used mathematical techniques. Consequently, the use of maximum likelihood mathematical techniques with a negative binomial statistical model would aid in the early detection of anthelmintic resistance using faecal egg count reductions and result in a lower probability of inappropriately assigning an anthelmintic as effective.

Animals↗

PubMed2003

Cell-cell affinity of senescent human erythrocytes.

During their 120-day life span, human red blood cells (RBC) undergo several physicochemical changes, including an increased tendency to aggregate in plasma or polymer solutions. This study was designed to examine potential associations between age-related differences in RBC mobility, aggregation, and membrane glycocalyx properties for cells suspended in buffer and in 3 g/dl solutions of 70.3 kDa dextran. A recent model for depletion-mediated RBC aggregation was employed to calculate the changes of glycocalyx properties that were consistent with experimental electrophoretic mobility (EPM) and aggregation data. Young and old cells were obtained by density separation, after which aggregation and EPM were determined versus ionic strength; old cells exhibited a two- to threefold greater aggregation in dextran. EPM of old cells was identical to young cells in polymer-free media yet was 4% greater in dextran. The greater EPM for old RBC indicates a larger polymer depletion layer, which could be explained either by a 10-15% decrease of their glycocalyx thickness or a similar percentage decrease of polymer penetration into their glycocalyx. The larger depletion layer leads to markedly elevated cell-cell affinities for old cells, with the computed affinity increases consistent with enhanced old RBC aggregation. These results provide a rational explanation for the aggregation and EPM behavior of old RBC, and raise the possibility of depletion-mediated interactions contributing to senescent cell removal from the circulation.

Cells, Cultured↗

PubMed2003

The public health burden of material deprivation: excess mortality in leading causes of death in Spain.

OBJECTIVE: The aim of the study is to investigate the burden of deprivation-associated excess of deaths by 10 leading causes of death in each gender and two age groups. DESIGN: A small-area ecological study using two indices of material deprivation drawn from 1991 census and mortality data aggregated for 1987-1995 was undertaken. SETTING: 2218 small areas in Spain. Data are presented by region. MAIN OUTCOME MEASURES: The 10 leading causes of death in each gender and two age groups were determined. RESULTS: The deprivation-associated excess mortality in the top 10 leading causes of death was 14.4 and 11% for males and females, respectively. Excess mortality in the 9-year period studied accounted for more than 222,000 deaths. A large proportion of excess deaths was found in causes related to smoking and alcohol consumption among males and diet-related causes of death among females. The most deprived regions within the country showed the highest mortality risk. CONCLUSIONS: Material deprivation appears to be manifested in high mortality rates differently by gender and region. It imposes a significant public health burden that demands urgently attention and action by health policy-makers.

Adolescent↗

PubMed2006

How is place of death from cancer changing and what affects it? Analysis of cancer registration and service data.

We aimed to compare trends in place of cancer death with the growth of palliative care and nursing home services, and investigate demographic, disease-related and area influences on individual place of death, using registration data for 216404 patients with breast, lung, colorectal and prostate cancer and aggregate data on services in South East England. Between 1985 and 1994 there was a trend away from hospital death (67-44%), to home (17-30%) and hospice death (8-20%). After 1995, this partly reversed. By 2002, hospital death rose to 47%, home death dropped to 23%, hospice death remained stable and nursing home death rose from 3 to 8%. Numbers of palliative care services increased, but trends for hospice and nursing home deaths most clearly followed the beds available. Cancer diagnosis and treatment influenced individual place of death, but between 1998 and 2002, age and area of residence were associated with most variation. Older patients and those living in more deprived areas died more often in hospitals and less often at home. Despite more palliative care services the proportion of people dying at home has not increased. Variation by age, deprivation and area of residence is unlikely to reflect patient preference. More active surveillance and planning must support policies for choice in end of life care.

Age Factors↗

PubMed1997

Research without billing data. Econometric estimation of patient-specific costs.

OBJECTIVES: This article describes a method for computing the cost of care provided to individual patients in health care systems that do not routinely generate billing data, but gather information on patient utilization and total facility costs. METHODS: Aggregate data on cost and utilization were used to estimate how costs vary with characteristics of patients and facilities of the US Department of Veterans Affairs. A set of cost functions was estimated, taking advantage of the department-level organization of the data. Casemix measures were used to determine the costs of acute hospital and long-term care. RESULTS: Hospitalization for medical conditions cost an average of $5,642 per US Health Care Financing Administration diagnosis-related group weight; surgical hospitalizations cost $11,836. Nursing home care cost $197.33 per day, intermediate care cost $280.66 per day, psychiatric care cost $307.33 per day, and domiciliary care cost $111.84 per day. Outpatient visits cost an average of $90.36. These estimates include the cost of physician services. CONCLUSIONS: The econometric method presented here accounts for variation in resource use caused by casemix that is not reflected in length of stay and for the effects of medical education, research, facility size, and wage rates. Data on non-Veteran's Affairs hospital stays suggest that the method accounts for 40% of the variation in acute hospital care costs and is superior to cost estimates based on length of stay or diagnosis-related group weight alone.

Cost Allocation↗

PubMed2005

Outdoor carbon monoxide, nitrogen dioxide, and sudden infant death syndrome.

AIMS: To investigate whether infants who died of SIDS were more likely to have higher acute and lifetime average exposures to outdoor carbon monoxide (CO) and nitrogen dioxide (NO2) than comparison healthy infants. METHODS: A total of 169 case and 169 matched control infants born between 1988 and 1992, were studied. CO and NO2 concentrations, averaged for all days within the infant's lifespan, and the last 30 days, 7 days, 3 days, and 1 day of life were obtained from air pollutant data provided by the California Air Resources Board. RESULTS: Based on monthly aggregated data, average CO and particularly NO2 were associated with SIDS count, even after adjustment for seasonal trends. SIDS outcome was not significantly associated with high average outdoor CO levels for any time period. However, high average outdoor NO2 levels on the last day of the infant's exposure period were significantly associated with SIDS; the adjusted odds ratio was 2.34 (95% CI 1.13 to 4.87). CONCLUSIONS: SIDS may be related to high levels of acute outdoor NO2 exposure during the last day of life. Further studies are needed to replicate this finding.

Air Pollutants↗

PubMed1995

Do you need to shop around? Age at marriage, spousal alternatives, and marital dissolution.

"This article attempts to shed light on the oft-observed relationship between age at marriage and marital dissolution by first deriving a hypothesis from marital search theory that relates both variables to the supply of spousal alternatives in the local marriage market. This hypothesis states that, relative to people who marry later in life, persons who marry at comparatively young ages will be especially susceptible to divorce when confronted with abundant alternatives to their current spouse. Marital history data from the National Longitudinal Survey of Youth were then merged with aggregated data from the Public Use Microdata Samples of the 1980 U.S. census to test this hypothesis." The author finds that "discrete-time event history analyses offer no support for this hypothesis. Although the risk of marital dissolution is highest where either husbands or wives chance numerous spousal alternatives, the impact of age at marriage on divorce is significantly weaker in marriage markets containing abundant remarriage opportunities. Some of the effect of age at marriage on marital dissolution is attributable to the detrimental impact of early marriage on educational attainment."

Americas↗

PubMed2000

Prevention validation and accounting platform: a framework for establishing accountability and performance measures of substance abuse prevention programs.

The field of substance abuse prevention has neither an overarching conceptual framework nor a set of shared terminologies for establishing the accountability and performance outcome measures of substance abuse prevention services rendered. Hence, there is a wide gap between what we currently have as data on one hand and information that are required to meet the performance goals and accountability measures set by the Government Performance and Results Act of 1993 on the other. The task before us is: How can we establish the accountability and performance measures of substance abuse prevention programs and transform the field of prevention into prevention science? The intent of this volume is to serve that purpose and accelerate the processes of this transformation by identifying the requisite components of the transformation (i.e., theory, methodology, convention on terms, and data) and by introducing an open forum called, Prevention Validation and Accounting (PREVA) Platform. The entire PREVA Platform (for short, the Platform) is designed as an analytic framework, which is formulated by a collectivity of common concepts, terminologies, accounting units, protocols for counting the units, data elements, and operationalizations of various constructs, and other summary measures intended to bring about an efficient and effective measurement of process input, program capacity, process output, performance outcome, and societal impact of substance abuse prevention programs. The measurement units and summary data elements are designed to be measured across time and across jurisdictions, i.e., from local to regional to state to national levels. In the Platform, the process input is captured by two dimensions of time and capital. Time is conceptualized in terms of service delivery time and time spent for research and development. Capital is measured by the monies expended for the delivery of program activities during a fiscal or reporting period. Program capacity is captured by fourteen measurement units, tapping into the dimensions of staff resources and community assets. Staff resources are, in turn, operationalized in terms of staff size, staff certification status, staff turnover rate, and the accreditation status of a provider agency. Community assets are operationalized by the number of community centers accessible to the funded agency, number of formalized teams or antidrug coalitions active in the catchment area, and other social/human services providers with whom the prevention agency has formalized networks. The totality of process output from all sources of program activities is reduced to eighteen classes of measures. These are operationalized by thirty-three summary measures. Some of these include: total count of events facilitated; total number of clients served; average number of clients served per event; clients served by single and multiple program sessions; classification of target population in terms of the severity of risk as defined by the Institute of Medicine; age groups and race/ethnicity of clients served; number of program participants retained by recurring programs; number of clients who have completed the program; penetration rates to the target population; client attrition rates; average referral rates per provider per time interval; referral success rates; and so on. All process output measures specified in the Platform are derived from two broad classes of events classified as either products or services. The collectivity of these measures is expected to present a cost-effective, parsimonious, yet comprehensive picture of the entire spectrum of the process output, i.e., "what came out of the program as program activities". For the measurement of performance outcomes, two types of data are incorporated into the Platform: outcome data from individuals and the behavior (or performance) of social indicators from aggregated data bases. Individual data are used to evaluate the outcome of substance abuse programs

Accounting↗

PubMed1997

Network's cardiology data help member groups benchmark performance, market services.

Data-driven cardiac network improves outcomes, reduces costs. Thirty-seven high-volume network member hospitals are using detailed demographic, procedure, and outcomes data in benchmarking and marketing efforts, and network physicians are using the aggregate data on 120,000 angioplasty and bypass procedures in research studies. Here are the details, plus sample reports.

Benchmarking↗

PubMed2003

Research strategies in developmental psychopathology: dimensional identity and the person-oriented approach.

This article deals with alternative research strategies for developmental psychopathology. It argues that most applications of statistical methods in empirical research are variable centered, not person oriented. As a result, conclusions are often drawn that fail to do justice to the diverse nature of populations. It is recommended that we take seriously the importance of the implications of data aggregation. The difficulties of making inferences from a more aggregated level of analysis to a less aggregated level are explained and exemplified. We explain that a set of variables displays dimensional identity if the variable relationships remain unchanged across the levels or categories of other variables. Data examples of intelligence divergence and of Child Behavior Checklist subpopulation differences show that lack of dimensional identity can lead to incorrect conclusions. Schmitz' theorems on aggregation and the validity of results at the aggregate level for individuals are illustrated using data from a study on the development of alcoholism and discussed from a person-oriented perspective. Statistical methods suitable for person-oriented data analysis are reviewed.

Adolescent↗

PubMed2001

Minority representation, prevalence of symptoms, and utilization of services in a large metropolitan hospice.

Minority access to and utilization of hospice services is gaining increasing attention in the field of health care delivery systems. This case study describes the 1997 ethnic and racial make-up of a large metropolitan hospice facility located in Arlington, Virginia and compares its composition with the regional community. Demographic data; aggregate physical and psychosocial problems; utilization of services; and admission, discharge, and mortality data were collected and summarized by race and ethnicity. The state provided 1997 regional mortality data by race and ethnicity. When hospice deaths were compared with regional deaths, the hospice provided service to 30% of Caucasians decedents, 20% of Asian decedents, 19% of Hispanic decedents, and 18% of African-American decedents. By using mortality data rather than census data, the discrepancy between minority and Caucasian populations is not as large as has been reported in previous research.

Aged↗

PubMed1984

A comparison of pressure-volume models in hydrocephalus.

Traditional descriptions of the pressure-volume properties of the craniospinal axis have expressed pressure as a function of volume. This study develops a theoretical and practical rationale for expressing volume as a function of pressure. We tested the rationale by comparing the two functions using pressure and volume data collected from 37 hydrocephalic patients during ventricular fluid removal. Two equivalent expressions were evaluated, one expressing pressure as an exponential function of volume and one relating volume as an exponential function of pressure. Each expression had three parameters, adjustable to the specific case. We used a nonlinear curve-fitting algorithm to determine the best estimate of the parameters. We could fit three-parameter exponential functions of either type to the data in all cases. We found a superior goodness-of-fit to aggregated data when expressing volume as a three-parameter exponential function of pressure changes. This finding is discussed in the context of the preferable number of parameters in a model and the interpretation of the terms in the models. This "reversed" volume-pressure relationship has importance in the development of more complicated models involving these same relationships.

Computers↗

PubMed2003

Estimating the number of helminthic infections in the Republic of Cameroon from data on infection prevalence in schoolchildren.

INTRODUCTION: The prevalence of infection with helminths is markedly dependent on age, yet estimates of the total number of infections are typically based on data only from school-aged children. Such estimates, although useful for advocacy, provide inadequate information for planning control programmes and for quantifying the burden of disease. Using readily available data on the prevalence of infection in schoolchildren, the relation between the prevalence of infection in school-aged children and prevalence in the wider community can be adequately described using species-specific models. This paper explores the reliability of this approach to predict the prevalence infection in the community and provides a model for estimating the total number of people infected in the Republic of Cameroon. METHODS: Using data on the prevalence of helminthic infection in school-aged children in Cameroon, the prevalence of infection in pre-school children and adults was estimated from species-specific linear and logistic regression models developed previously. The model predictions were then used to estimate the number of people infected in each district in each age group in Cameroon. RESULTS: For Cameroon, if only the prevalence of infection in schoolchildren is used, the number of people infected with each helminthic species will be overestimated by up to 32% when compared with the estimates provided by the species-specific models. The calculation of confidence intervals supports the statistical reliability of the model since a narrow range of parameter estimates is evident. Furthermore, this work suggests that estimation of national prevalence of infection and the number infected will be enhanced if data are stratified by age; this model represents a useful planning tool for obtaining more accurate estimates. Estimates based on data aggregated from three geographical levels (district, regional, and national) show that summarizing prevalence data at the national level will result in biases of up to 19%. Such biases reflect differences in the geographical distribution for the prevalence of each species. DISCUSSION: Developing more accurate estimates requires a better understanding of the differences in the spatial heterogeneity of each species and also better methods of incorporating this information when making estimates.

Adolescent↗

PubMed1989

Dental hygienists' anti-tobacco role: educational perspectives.

Dental hygienists need to assume a proactive health education role concerning tobacco use. To help measure, define, and broaden this role, a study was conducted to assess dental hygienists' current clinical practice behaviors, attitudes, and perceived curriculum adequacy concerning anti-tobacco efforts. The relationships among these variables and respondents' academic degree and year of graduation were analyzed. The study population consisted of a proportionate random sample of 500 dental hygienists in five states and the District of Columbia. A self-administered questionnaire yielded a response rate of 79.4 percent. Based on chi-square analyses of individual items, it was found that, when controlling for degree held, year of graduation was not significantly related to clinical practice behaviors or attitudes, but was significantly related to the majority of curriculum adequacy items. Academic degree, when controlled for year of graduation, was not significantly related to clinical practice behaviors, but was related to one attitude and two curriculum adequacy items. Analysis of variance and Duncan's multiple range test revealed the following significant relationships for aggregate data: year of graduation and degree held appeared to have no relationship to aggregate clinical practice behaviors or attitudes, M.S. degree respondents assigned higher curriculum adequacy ratings than did other subjects, and respondents who graduated prior to 1972 assigned their curricula more negative adequacy ratings than did all other graduates. The most recent graduates rated their curricula the most positively. The study's overall findings suggest that a fairly well-developed role for dental hygienists in anti-tobacco efforts exists. Given the current emphasis on health promotion, prevention, and holism in the provision of oral health care, it is commendable, but not surprising, that dental hygiene programs appear to have made positive modifications over time in tobacco-related content.

Attitude of Health Personnel↗

PubMed1993

The Singapore Renal Registry: an overview.

The Singapore Renal Registry (SRR) is created to collect and analyse information on incidence, prevalence, morbidity and mortality of End Stage Renal Disease (ESRD) in Singapore. Its objectives include the implementation of a consolidated renal disease data system, report on incidence and trends over time of renal disease, analyse aggregate data on effect of various modalities of therapy, identify problems and opportunities for special studies and research. The framework of the Registry encompasses the following areas: incidence, demographics and causes of ESRD, utilization of treatment modalities, institutions providing treatment, morbidity and survival rates of various treatment modalities, the paediatric sector, the private sector, international comparisons and research areas. This overview will present whatever existing data and renal statistics that are currently available on a regional or national basis. The collection of nationwide statistics will provide a database to formulate national averages of individual renal statistics. Statistics can also be collected to provide valuable data for planning and projection for future needs.

Adult↗

PubMed2001

Multivariate analysis of refractive data: mathematics and statistics of spherocylinders.

PURPOSE: To develop methods for multivariate statistical analysis of spherocylinders and to use these methods to compare autorefraction and manifest subjective refraction in 50 healthy eyes. SETTING: Department of Ophthalmology, Arhus University Hospital, Arhus, Denmark. METHODS: A method was developed to transform a spherocylinder to a suitable format as a spherical equivalent power (SEP) and 2 polar values, separated by an arch of 45 degrees, a so-called power-vector format. The accuracy of autorefraction was defined as the difference between autorefraction and manifest refraction, using the described power vector. These entities were subjected to multivariate analysis using the Hotelling T2 test. A method of graphic analysis was developed, using matrix algebra and computation of eigenvectors and eigenvalues. RESULTS: For individual data, the variation was considerably larger for the SEP than for the astigmatism. For aggregate data, univariate, bivariate, and trivariate statistical analysis did not demonstrate significant average differences between the 2 refraction methods. No refractive components and no combinations of refractive components displayed significant mean differences. CONCLUSIONS: The study confirmed our clinical experience that the astigmatism derived from autorefraction is nearly identical to manifest refraction, while the sphere needs some adjustment. In groups of healthy eyes, autorefraction can be used as a substitute for manifest refraction. Statistical analysis of spherocylinders, including evaluation of refractive procedures, can be performed in an exact manner with multivariate statistics.

Adolescent↗