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Cindy L Christiansen

Publications and source records attributed to Cindy L Christiansen.

17 recordsLinked to original sources
PubMed2006

Does periodontal care improve glycemic control? The Department of Veterans Affairs Dental Diabetes Study.

OBJECTIVES: Report results of a randomized-clinical trial of the efficacy of periodontal care in the improvement of glycemic control in 165 veterans with poorly controlled diabetes over 4 months. METHODS: Outcomes were change in Haemoglobin A1c (HbA1c) in the Early Treatment versus untreated (Usual Care) groups and percent of participants with decreases in HbA1c. Analyses included simple/multiple variable linear/logistic regressions, adjusted for baseline HbA1c, age, and duration of diabetes. RESULTS: Unadjusted analyses showed no differences between groups. After adjustment for baseline HbA1c, age, and diabetes duration, the mean absolute HbA1c change in the Early Treatment group was -0.65% versus -0.51% in the Usual Care group (p=0.47). Adjusted odds for improvement by 0.5% in the Early Treatment group was 1.67 (95% confidence interval: 0.84, 3.34, p=0.14). Usual Care subjects were twice as likely to increase insulin from baseline to 4 months (20% versus 11%, p=0.12) and less likely to decrease insulin (1% versus 6%, p=0.21) than Early Treatment subjects. Among insulin users at baseline, more increased insulin in the Usual Care group (40% versus 21%, p=0.06). CONCLUSIONS: No significant benefit was found for periodontal therapy after 4 months in this study; trends in some results were in favour of periodontal treatment.

Age Factors↗
PubMed2006

Performance of statistical models to predict mental health and substance abuse cost.

BACKGROUND: Providers use risk-adjustment systems to help manage healthcare costs. Typically, ordinary least squares (OLS) models on either untransformed or log-transformed cost are used. We examine the predictive ability of several statistical models, demonstrate how model choice depends on the goal for the predictive model, and examine whether building models on samples of the data affects model choice. METHODS: Our sample consisted of 525,620 Veterans Health Administration patients with mental health (MH) or substance abuse (SA) diagnoses who incurred costs during fiscal year 1999. We tested two models on a transformation of cost: a Log Normal model and a Square-root Normal model, and three generalized linear models on untransformed cost, defined by distributional assumption and link function: Normal with identity link (OLS); Gamma with log link; and Gamma with square-root link. Risk-adjusters included age, sex, and 12 MH/SA categories. To determine the best model among the entire dataset, predictive ability was evaluated using root mean square error (RMSE), mean absolute prediction error (MAPE), and predictive ratios of predicted to observed cost (PR) among deciles of predicted cost, by comparing point estimates and 95% bias-corrected bootstrap confidence intervals. To study the effect of analyzing a random sample of the population on model choice, we re-computed these statistics using random samples beginning with 5,000 patients and ending with the entire sample. RESULTS: The Square-root Normal model had the lowest estimates of the RMSE and MAPE, with bootstrap confidence intervals that were always lower than those for the other models. The Gamma with square-root link was best as measured by the PRs. The choice of best model could vary if smaller samples were used and the Gamma with square-root link model had convergence problems with small samples. CONCLUSION: Models with square-root transformation or link fit the data best. This function (whether used as transformation or as a link) seems to help deal with the high comorbidity of this population by introducing a form of interaction. The Gamma distribution helps with the long tail of the distribution. However, the Normal distribution is suitable if the correct transformation of the outcome is used.

Aged↗
PubMed2006

Study design, recruitment, and baseline characteristics: the Department of Veterans Affairs Dental Diabetes Study.

OBJECTIVES: We are conducting a clinical trial of the efficacy of periodontal therapy in the improvement of glycaemic control in veterans with poorly controlled diabetes. This report describes study design, recruitment and randomization and compares baseline characteristics of the sample frame with those randomized into study groups. METHODS: Veterans with poorly controlled diabetes were randomized in two groups: immediate periodontal therapy ("early treatment") or usual care followed by periodontal therapy ("deferred treatment"). Half of each group continued care for 12 months; the other half returned to their usual care. We studied baseline patient characteristics, self-reported health measures, and clinical examination data. We examined means for continuous variables, frequencies for categorical variables and compared groups using t-tests and chi(2) tests (alpha=0.05 for both). RESULTS: The 193 randomized participants were younger (58 years) and had slightly higher HbA1c (10.2%) than the 2534 non-randomized participants (64 years, HbA1c =9.8%). The deferred treatment group was more likely than the early treatment group to have a history of stroke, transient ischaemic attacks, and less likely to be current or former smokers. CONCLUSIONS: The mechanism for randomization was largely successful in this study.

Age Factors↗
PubMed2006

Development and validation of a psychiatric case-mix system.

BACKGROUND: Although difficulties in applying risk-adjustment measures to mental health populations are increasingly evident, a model designed specifically for patients with psychiatric disorders has never been developed. OBJECTIVE: Our objective was to develop and validate a case-mix classification system, the "PsyCMS," for predicting concurrent and future mental health (MH) and substance abuse (SA) healthcare costs and utilization. SUBJECTS: Subjects included 914,225 veterans who used Veterans Administration (VA) healthcare services during fiscal year 1999 (FY99) with any MH/SA diagnosis (International Classification of Diseases, 9th Revision, Clinical Modification [ICD-9-CM] codes 290.00-312.99, 316.00-316.99). METHODS: We derived diagnostic categories from ICD-CM codes using Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition definitions, clinical input, and empiric analyses. Weighted least-squares regression models were developed for concurrent (FY99) and prospective (FY00) MH/SA costs and utilization. We compared the predictive ability of the PsyCMS with several case-mix systems, including adjusted clinical groups, diagnostic cost groups, and the chronic illness and disability payment system. Model performance was evaluated using R-squares and mean absolute prediction errors (MAPEs). RESULTS: Patients with MH/SA diagnoses comprised 29.6% of individuals seen in the VA during FY99. The PsyCMS accounted for a distinct proportion of the variance in concurrent and prospective MH/SA costs (R=0.11 and 0.06, respectively), outpatient MH/SA utilization (R=0.25 and 0.07), and inpatient MH/SA utilization (R=0.13 and 0.05). The PsyCMS performed better than other case-mix systems examined with slightly higher R-squares and lower MAPEs. CONCLUSIONS: The PsyCMS has clinically meaningful categories, demonstrates good predictive ability for modeling concurrent and prospective MH/SA costs and utilization, and thus represents a useful method for predicting mental health costs and utilization.

Aged↗
PubMed2006

Health status among 28,000 women veterans. The VA Women's Health Program Evaluation Project.

BACKGROUND: Male veterans receiving Veterans Health Administration (VA) care have worse health than men in the general population. Less is known about health status in women veteran VA patients, a rapidly growing population. OBJECTIVE: To characterize health status of women (vs men) veteran VA patients across age cohorts, and assess gender differences in the effect of social support upon health status. DESIGN AND PATIENTS: Data came from the national 1999 Large Health Survey of Veteran Enrollees (response rate 63%) and included 28,048 women and 651,811 men who used VA in the prior 3 years. MEASUREMENTS: Dimensions of health status from validated Veterans Short Form-36 instrument; social support (married, living arrangement, have someone to take patient to the doctor). RESULTS: In each age stratum (18 to 44, 45 to 64, and > or =65 years), Physical Component Summary (PCS) and Mental Component Summary (MCS) scores were clinically comparable by gender, except that for those aged > or =65, mean MCS was better for women than men (49.3 vs 45.9, P<.001). Patient gender had a clinically insignificant effect upon PCS and MCS after adjusting for age, race/ethnicity, and education. Women had lower levels of social support than men; in patients aged <65, being married or living with someone benefited MCS more in men than in women. CONCLUSIONS: Women veteran VA patients have as heavy a burden of physical and mental illness as do men in VA, and are expected to require comparable intensity of health care services. Their ill health occurs in the context of poor social support, and varies by age.

Adult↗
PubMed2005

Evaluating the patient safety indicators: how well do they perform on Veterans Health Administration data?

BACKGROUND: The Patient Safety Indicators (PSIs), an administrative data-based tool developed by the Agency for Healthcare Research and Quality, are increasingly being used to screen for potential in-hospital patient safety problems. Although the Veterans Health Administration (VA) is a national leader in patient safety, accurate information on the epidemiology of patient safety events in the VA is still unavailable. OBJECTIVES: Our objectives were to: (1) apply the AHRQ PSI software to VA administrative data to identify potential instances of compromised patient safety; (2) determine occurrence rates of PSI events in the VA; and (3) examine the construct validity of the PSIs. METHODS: We examined differences between observed and risk-adjusted PSI rates in the VA, compared VA and non-VA PSI rates, and investigated the construct validity of the PSIs by examining correlations of the PSIs with other outcomes of VA hospitalizations. RESULTS: We identified 11,411 PSI events in the VA nationwide in FY'01. Observed PSI rates per 1000 discharges ranged from 0.007 for "transfusion reaction" to 155.5 for "failure to rescue." There were significant, although small, differences between VA and non-VA risk-adjusted PSI rates. Hospitalizations with PSI events had longer lengths of stay, higher mortality, and higher costs than those without PSI events. CONCLUSIONS: Our results suggest that the PSIs may be useful as a patient safety screening tool in the VA. Our PSI rates were consistent with the national incidence of low rates; however, differences between VA and non-VA rates suggest that inadequate case-mix adjustment may be contributing to these findings.

Aged↗
PubMed2004

Assessment of optimal size and composition of the U.S. National Registry of hematopoietic stem cell donors.

BACKGROUND: The National Marrow Donor Program (NMDP) receives federal funding to operate a registry of over 4 million volunteer donors for patients in need of a hematopoietic stem cell transplant. Because minority patients are less likely to find a suitably matched donor than whites, special efforts have been aimed toward recruitment of minorities. Significant financial resources are required to recruit and tissue type additional volunteer donors. METHODS: Population genetics models have been constructed to project likelihoods of finding a human leukocyte antigen (HLA)-matched donor for patients of various racial/ethnic groups. These projections have been made under a variety of strategies for expansion of the NMDP Registry. Cost-effectiveness calculations incorporated donor unavailability and other barriers to transplantation. RESULTS: At current recruitment rates, the probability of an available HLA-A,B,DRB1 matched donor is projected to increase from 27% to 34%; 45% to 54%; 75% to 79%; and 48% to 55%, for blacks, Asians/Pacific Islanders, whites and Hispanics, respectively, by the year 2007. Substantial increases in minority recruitment would have only modest impacts on these projections. These projections are heavily affected by donor availability rates, which are less than 50% for minority volunteers. CONCLUSIONS: Continued recruitment of additional volunteers can improve the likelihood of finding an HLA-matched donor, but will still leave significant numbers of patients of all racial/ethnic groups without a match. Efforts to improve donor availability (especially among minorities) and to increase the number of patients with access to the NMDP Registry may prove to be more cost-effective means of increasing transplants.

Genetics, Population↗
PubMed2004

Burden of medical illness in women with depression and posttraumatic stress disorder.

BACKGROUND: Depression and posttraumatic stress disorder (PTSD) are important women's health issues. Depression is known to be associated with poor physical health; however, associations between physical health and PTSD, a common comorbidity of depression, have received less attention. OBJECTIVES: To examine number of medical symptoms and physical health status in women with PTSD across age strata and benchmark them against those of women with depression alone or with neither depression nor PTSD. METHODS: A random sample of Veterans Health Administration enrollees received a mailed survey in 1999-2000 (response rate, 63%). The 30 865 women respondents were categorized according to whether a health care provider had ever told them that they had PTSD, depression (without PTSD), or neither. Outcomes were self-reported medical conditions and physical health status measured with the Veterans SF-36 instrument, a version of the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36) modified for use in veteran populations. RESULTS: Across age strata, women with PTSD (n = 4348) had more medical conditions and worse physical health status (physical functioning, role limitations due to physical problems, bodily pain, and energy/vitality scales from the Veterans SF-36) than women with depression alone (n = 7580) or neither (n = 18 937). In age-adjusted analyses, the Physical Component Summary score was on average 3.4 points lower in women with depression alone and 6.3 points lower in women with PTSD than in women with neither (P<.001). CONCLUSIONS: Posttraumatic stress disorder is associated with a greater burden of medical illness than is seen with depression alone. The presence of PTSD may account for an important component of the excess medical morbidity and functional status limitations seen in women with depression.

Adult↗
PubMed2003

Tooth retention as an indicator of quality dental care: development of a risk adjustment model.

BACKGROUND: Retaining teeth improves oral health and quality of life. Thus, receipt of a root canal (vs. a tooth extraction) is a useful indicator of the quality of dental care. However, use of this quality measure without adjusting for the severity of oral disease could lead to spurious conclusions. OBJECTIVES: This paper describes the development of a dental severity adjustment methodology. RESEARCH DESIGN: Retrospective study. SUBJECTS: 54,423 users of Department of Veterans Affairs (VA) dental care who had either root canal therapy or a tooth extraction at a VA facility in Fiscal year 1998. MEASURES: International Classification of Disease Clinical Modification codes for dental diagnoses and comorbid medical conditions. We modeled the effects of dental disease severity in logistic regression models of the probability of receiving a root canal, using both conceptual and Modified Delphi-Panel derived models, adjusting for age, and medical comorbidities. RESULTS: Conceptual and Modified Delphi models performed similarly. The dental disease severity adjustments increased the fit in models of the probability of receiving a root canal (C-statistic = 0.822 for the conceptual model and 0.804 for the Modified Delphi Panel model) compared with the model including comorbid medical conditions alone (C-statistic = 0.561). CONCLUSIONS: Risk adjustment for dental disease severity improves the fit of models of the probability of receiving a root canal. Studies of the quality of dental care should consider employing risk-adjusted models.

Alcoholism↗
PubMed2003

Racial variations in dental procedures: the case of root canal therapy versus tooth extraction.

BACKGROUND: Racial disparities have been widely documented in medical care, but variations in dental care have not been well examined. OBJECTIVES: To determine if there is racial variation in use of root canal therapy versus tooth extraction across different levels of dental insurance coverage and adjusting for other factors known to influence treatment decisions. METHODS: Within 3 different categories of insurance coverage, we examined whether there were racial differences in the provision of the tooth-sparing treatment of root canal therapy (vs. tooth extraction) among 54,423 users of outpatient Veterans Affairs dental care in 1998. Regression analyses adjusted for the severity of tooth- and gum-related disease, age, sex, medical and psychiatric comorbidities, prior use of preventive dental services, tooth extraction and root canal therapy, and clustering by geographic region. RESULTS: In the adjusted regression models, black patients and those with unknown race were less likely overall to receive root canal therapy than whites, whereas Asians were more likely. Among patients with eligibility for continuing and comprehensive dental care, blacks were less likely and Asians more likely to receive root canals than whites. For patients covered only for emergency dental care, Hispanics had a higher likelihood of receiving root canal therapy. Among all other types of coverage, there were no significant racial differences in the care received. CONCLUSION: We observed substantial racial variations in the provision of root canal therapy among patients treated in Department of Veterans Affairs dental clinics. Future research should identify the causes of such variations.

Black or African American↗
PubMed2003

Potential organ-donor supply and efficiency of organ procurement organizations.

The authors estimated the supply of organ donors in the U.S. and also according to organ procurement organizations (OPOs). They estimated the number of donors in the U.S. to be 16,796. Estimates of the number of potential donors for each OPO were used to calculate the level of donor efficiency (actual donors as a percent of potential donors). Overall, donor efficiency for OPOs was 35 percent; the majority was between 30- and 40-percent efficient. Although there is room to improve donor efficiency in the U.S., even a substantial improvement will not meet the Nation's demand for organs.

Centers for Medicare and Medicaid Services, U.S.↗
PubMed2002

Screening mammograms by community radiologists: variability in false-positive rates.

BACKGROUND: Previous studies have shown that the agreement among radiologists interpreting a test set of mammograms is relatively low. However, data available from real-world settings are sparse. We studied mammographic examination interpretations by radiologists practicing in a community setting and evaluated whether the variability in false-positive rates could be explained by patient, radiologist, and/or testing characteristics. METHODS: We used medical records on randomly selected women aged 40-69 years who had had at least one screening mammographic examination in a community setting between January 1, 1985, and June 30, 1993. Twenty-four radiologists interpreted 8734 screening mammograms from 2169 women. Hierarchical logistic regression models were used to examine the impact of patient, radiologist, and testing characteristics. All statistical tests were two-sided. RESULTS: Radiologists varied widely in mammographic examination interpretations, with a mass noted in 0%-7.9%, calcification in 0%-21.3%, and fibrocystic changes in 1.6%-27.8% of mammograms read. False-positive rates ranged from 2.6% to 15.9%. Younger and more recently trained radiologists had higher false-positive rates. Adjustment for patient, radiologist, and testing characteristics narrowed the range of false-positive rates to 3.5%-7.9%. If a woman went to two randomly selected radiologists, her odds, after adjustment, of having a false-positive reading would be 1.5 times greater for the radiologist at higher risk of a false-positive reading, compared with the radiologist at lowest risk (95% highest posterior density interval [similar to a confidence interval] = 1.17 to 2.08). CONCLUSION: Community radiologists varied widely in their false-positive rates in screening mammograms; this variability range was reduced by half, but not eliminated, after statistical adjustment for patient, radiologist, and testing characteristics. These characteristics need to be considered when evaluating false-positive rates in community mammographic examination screening.

Adult↗
PubMed2002

Effectiveness of thrombolytic therapy for acute myocardial infarction in the elderly: cause for concern in the old-old.

BACKGROUND: National guidelines have encouraged increased use of thrombolytic therapy for elderly patients with acute myocardial infarction (AMI). However, evidence supporting thrombolytic therapy in patients 75 years and older is lacking. In a retrospective cohort study of 2659 elderly AMI patients, we determined the association between thrombolytic use and in-hospital mortality by age and among patients with or without absolute or relative contraindications to thrombolytic treatment. METHODS: We abstracted the medical records of 2659 elderly patients admitted with AMI at 37 Minnesota community hospitals between 1992 and 1996. The main outcome measure was in-hospital mortality, controlling for demographic, clinical, comorbidity, and severity-of-illness variables. RESULTS: Sixty-three percent of 719 eligible patients received thrombolytic therapy. Twenty-seven percent of thrombolytic recipients had absolute contraindications to treatment. Patients receiving thrombolytic agents had fewer and less severe comorbidities than those not receiving thrombolytic therapy. There was a 4% increase in the odds of death for every 1-year increase in age for all thrombolytic recipients vs nonrecipients (odds ratio [OR], 1.04 per year; 95% confidence interval [CI], 1.01-1.08; P =.03). Among patients with 1 or more contraindication, the OR for death associated with thrombolytic use was 1.57 (95% CI, 1.03-2.40; P =.04). The adjusted odds of death among eligible thrombolytic recipients (vs nonrecipients) increased significantly with age (OR, 1.08 per year; 95% CI, 1.02-1.14; P =.008). Among eligible patients aged 80 to 90 years, the predicted odds of death among thrombolytic recipients vs nonrecipients was 1.4. Among eligible patients younger than 80 years, thrombolytic use was associated with reduced mortality. CONCLUSIONS: Our findings suggest the need for more research on the effectiveness of thrombolytic therapy for AMI patients 75 years and older and for more careful selection of elderly patients for this treatment.

Aged↗
PubMed2002

Profiling nursing homes using Bayesian hierarchical modeling.

OBJECTIVES: New methods developed to improve the statistical basis of provider profiling may be particularly applicable to nursing homes. We examine the use of Bayesian hierarchical modeling in profiling nursing homes on their rate of pressure ulcer development. DESIGN: Observational study using Minimum Data Set data from 1997 and 1998. SETTING: A for-profit nursing home chain. PARTICIPANTS: Residents of 108 nursing homes who were without a pressure ulcer on an index assessment. MEASUREMENTS: Nursing homes were compared on their performance on risk-adjusted rates of pressure ulcer development calculated using standard statistical techniques and Bayesian hierarchical modeling. RESULTS: Bayesian estimates of nursing home performance differed considerably from rates calculated using standard statistical techniques. The range of risk-adjusted rates among nursing homes was 0% to 14.3% using standard methods and 1.0% to 4.8% using Bayesian analysis. Fifteen nursing homes were designated as outliers based on their z scores, and two were outliers using Bayesian modeling. Only one nursing home had greater than a 50% probability of having a true rate of ulcer development exceeding 4%. CONCLUSIONS: Bayesian hierarchical modeling can be successfully applied to the problem of profiling nursing homes. Results obtained from Bayesian modeling are different from those obtained using standard statistical techniques. The continued evaluation and application of this new methodology in nursing homes may ensure that consumers and providers have the most accurate information regarding performance.

Bayes Theorem↗
PubMed2002

Risk-adjusted mortality rates as a potential outcome indicator for outpatient quality assessments.

OBJECTIVE: The quality of outpatient medical care is increasingly recognized as having an important impact on mortality. We examined whether a clinically credible risk adjustment methodology can be developed for outpatient quality assessments. RESEARCH DESIGN: This study used data from the 1998 National Survey of Ambulatory Care Patients, a prospective monitoring system of outcomes of patients receiving ambulatory care in the Veterans Affairs (VA) integrated service networks. SUBJECTS: Thirty-one thousand eight hundred twenty-three patients were followed for 18 months. MEASURES: The main study outcome measures were observed and risk-adjusted mortality rates. RESULTS: Of the 31,823 patients, 1559 (5%) died during the 18-months of follow-up. Observed mortality rates across the 22 VA integrated service networks varied significantly from 3.3% to 6.7% (P <0.001). Age, gender, comorbidities (Charlson Index), physical health, and mental health were significant predictors of dying. The resulting risk-adjusted mortality model performed well in cross-validated tests of discrimination (c-statistic = 0.768; 95% CI, 0.749-0.788) and calibration. Analysis of variance confirmed that the 22 integrated service networks differed in their average level of expected risk (P <0.001). Risk-adjusted rates and ranks of the networks differed considerably from unadjusted ratings. CONCLUSIONS: Risk-adjusted mortality rates may be a useful outcome measure for assessing quality of outpatient care. We have developed a clinically credible risk adjustment model with good performance properties using sociodemographics, diagnoses, and functional status data. The resulting risk adjustment model altered assessments of the performance of the integrated service networks when compared with the unadjusted mortality rates.

Aged↗
PubMedDate not supplied

Do different case-mix measures affect assessments of provider efficiency? Lessons from the Department of Veterans Affairs.

Although case-mix adjustment is critical for provider profiling, little is known regarding whether different case-mix measures affect assessments of provider efficiency. We examine whether two case-mix measures, Adjusted Clinical Groups (ACGs) and Diagnostic Cost Groups (DCGs), result in different assessments of efficiency across service networks within the Department of Veterans Affairs (VA). Three profiling indicators examine variation in resource use. Although results from the ACGs and DCGs generally agree on which networks have greater or lesser efficiency than average, assessments of individual network efficiency vary depending upon the case-mix measure used. This suggests that caution should be used so that providers are not misclassified based on reported efficiency.

Aged↗