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R S Dittus

Publications and source records attributed to R S Dittus.

At least 37 records · Page 2Linked to original sources
PubMed1995

Patient outcomes following unicompartmental or bicompartmental knee arthroplasty. A meta-analysis.

The purpose of this study was to summarize the literature describing patient outcomes following unicompartmental and bicompartmental knee arthroplasty. Original studies were included in this meta-analysis if they enrolled 10 or more patients at the time of an initial knee arthroplasty and measured patient outcomes using a global knee rating scale. Forty-six studies on unicompartmental prostheses and 18 studies on bicompartmental prostheses met these criteria. For unicompartmental studies, the total number of enrolled patients was 2,391, with a mean enrollment of 47 patients and a mean follow-up period of 4.6 years. The mean patient age was 66 years; 67% were women, 75% had osteoarthritis, and 16% underwent bilateral knee arthroplasty. The mean postoperative global rating scale score was 80.9. The overall complication rate was 18.5% and the revision rate was 9.2%. Studies published after 1987 reported better outcomes, but also tended to enroll older patients and patients with osteoarthritis and higher preoperative knee rating scores. For bicompartmental studies, the total number of enrolled patients was 884, with a mean enrollment of 44 patients and a mean follow-up period of 3.6 years. The mean patient age was 61 years; 79% were women, 31% had osteoarthritis, and 29% underwent a bilateral arthroplasty. The mean postoperative global rating scale score was 78.3. The overall complication rate was 30% and the revision rate was 7.2%. Although bicompartmental studies reported lower mean postoperative global rating scale scores, these studies tended to enroll patients with worse preoperative knee rating scores. Recent improvements in patient outcomes following unicompartmental knee arthroplasty appear to be due, at least partially, to changes in patient selection criteria. Patient outcomes appear to be worse for bicompartmental arthroplasties than for other prosthetic designs; however, patients enrolled in these studies had more poorly functioning knees before surgery and actually had greater absolute improvements in global knee rating scores.

Aged↗
PubMed1995

A comparison of various methods of collecting self-reported health outcomes data among low-income and minority patients.

In a randomized trial of different data collection methods, we challenged the untested assumption that reliable data cannot be obtained from lower-income and/or minority patients by self-administered questionnaires. We tested three methods of data collection among a sample of lower-income and minority patients (n = 697) in Indianapolis at a site for the Type II Diabetes Patient Outcomes Research Team. The study included a questionnaire literacy screening instrument to assess patients' functional literacy. Based on their functional literacy, patients were randomized to one of three methods of data collection: mail-out/mail-back, hand-out/assisted, or the in-home interview. We constructed a tiered system for reassigning nonresponders to alternative methods of data collection, using the in-home interview as the fall-back strategy. We compared the response rates, item completion rates, and internal consistency reliabilities of self-reported health status measures between patients with and without literacy limitations and across the three methods of data collection. Patients with and without literacy limitations, across methods of data collection, provided high-quality data, as evidenced by high item completion rates (> 84%) and high reliability assessments (internal consistency reliability coefficients > .80) for each health status measure. As part of the tiered study design, nonresponders randomized to either the mail-out/mail-back or the hand-out/assisted method were interviewed. These patients were significantly older, had significantly lower education and income levels, and had significantly poorer self-reported visual function as compared with those who responded to the originally assigned method. We conclude that expensive, labor-intensive data collection methods, such as in-home interviews, are not necessary for many low-income, minority patients to generate high-quality, reliable health status data. Using appropriate screening instruments, those patient subgroups needing special help can be screening instruments, those patient subgroups needing special help can be identified and targeted for more expensive data collection methods. This tiered approach has policy implications for the cost, feasibility, and quality of data collection in health outcomes research.

Aged↗
PubMed1994

Waiting times for knee-replacement surgery in the United States and Ontario.

BACKGROUND: Canada, which has universal single-payer health insurance, is often criticized for waiting times for surgery that are longer than those in the United States. We compared waiting times for orthopedic consultations and knee-replacement surgery and patients' acceptance of them in the United States and in the province of Ontario, Canada. METHODS: A stratified random sample of 1486 Medicare recipients (629 from the U.S. national sample, 428 from Indiana, and 429 from western Pennsylvania) and 516 people from Ontario who had been hospitalized for knee replacement between 1985 and 1989 were surveyed by mail in 1992. Patients were asked how long they had waited to see an orthopedic surgeon and to have surgery, the acceptability of these waiting times, and their overall satisfaction with surgery. RESULTS: About 80 percent of the questionnaires were returned, but not all the respondents answered all the questions. The rate of response to specific questions was about 60 to 65 percent in both countries. The median waiting time for an initial orthopedic consultation was two weeks in the United States and four weeks in Ontario. The median waiting time for knee replacement after the operation had been planned was three weeks in the United States and eight weeks in Canada. In the United States, 95 percent of patients in the national sample considered their waiting time for surgery acceptable, as compared with 85.1 percent in Ontario. Overall satisfaction with surgery ("very or somewhat satisfied") was 85.3 percent for all U.S. respondents and 83.5 percent for Canadian respondents. CONCLUSIONS: Waiting times for initial orthopedic consultation and for knee-replacement surgery were longer in Ontario than in the United States, but overall satisfaction with surgery was similar.

Aged↗
PubMed1994

Risk factors for underimmunization in poor urban infants.

OBJECTIVE: To assess risk factors for underimmunization in poor urban infants. DESIGN: Prospective cohort study. SETTING: A large municipal teaching hospital in the Midwest. PARTICIPANTS: A total of 464 healthy, full-term newborn infants delivered at a large municipal teaching hospital who were to be discharged to the care of their mothers. Mothers were interviewed 24 to 72 hours post partum regarding personal and financial characteristics and 9 to 12 months later to determine where immunizations had been received. MAIN OUTCOME MEASURES: Immunization status at 3 and 7 months of age. RESULTS: Despite availability of free vaccine to most patients, only 67% had received their first set of immunizations by 3 months of age, and only 29% were up-to-date by 7 months of age. Marital status, coresidence with the infant's grandmother, adequacy of prenatal care, and perceived barriers to care were significant independent predictors of initiation of immunizations by 3 months and completion of immunization by 7 months. Poverty was also an independent predictor of immunization status at 7 months. Perceived susceptibility to common symptoms and perceived benefit of medical care to prevent disease were inversely related to immunization status at 7 months. CONCLUSIONS: These data suggest that poor urban infants of single mothers and of mothers who received inadequate prenatal care, and those not living with their grandmother should be targeted for tracking and follow-up to ensure adequate immunization. The provision of free vaccine alone will not guarantee adequate immunization coverage of poor urban children.

Adult↗
PubMed1994

Patient outcomes following tricompartmental total knee replacement. A meta-analysis.

OBJECTIVE: To provide estimates of patient outcomes following tricompartmental knee replacement and to examine variation in outcomes due to patient and prosthesis characteristics. DATA SOURCES: English-language articles identified through a computerized literature search and bibliography review. STUDY SELECTION: Studies were included if they enrolled 10 or more patients at the time of initial knee replacement and measured patient outcomes using a global knee-rating scale. DATA EXTRACTION: Each study was subjected to a blinded qualitative assessment and unblinded abstraction of patient characteristics, surgical techniques, and outcomes. DATA SYNTHESIS: A total of 130 studies reporting patient outcomes on 154 cohorts satisfied inclusion criteria. The total number of enrolled patients was 9879 with a mean enrollment of 64.1 patients. The mean follow-up was 4.1 years. The mean patient age was 65.0 years, 71.7% of patients were women, 62.6% had osteoarthritis, and 26.6% underwent bilateral knee replacement. Global rating scale scores improved by 100% for the typical enrolled patient, and 89.3% of patients reported good or excellent outcomes. Anatomic classification of the prosthesis, percentage of enrolled patients with osteoarthritis, publication year, and number of enrolled patients explained 27% of the variation in reported mean postoperative global rating scale scores. The weighted mean complication rate was 18.1%, and the mean mortality rate per year of follow-up was 1.5%. The overall rate of revision during 4.1 years was 3.8%. CONCLUSIONS: Tricompartmental knee replacement was a safe and effective procedure for the patients reported in these studies. The knee pathology and the type of prosthesis were significant predictors of outcomes. Limitations in the reporting style of these articles severely constrain the ability to explore variation in outcomes due to study, patient, or prosthesis characteristics and restrict their generalizability.

Aged↗
PubMed1994

Deciphering the physician note.

Objective information about legibility of physician handwriting is scant. This retrospective chart review compared handwritten general medicine clinic chart notes from internal medicine faculty and housestaff with their typed counterparts. The written counterparts took 11 seconds (46%) longer to read and 5 seconds (11%) longer to answer comprehension questions. The authors' comprehension measure (developed specifically for ambulatory clinic notes) was only slightly higher for typed notes. The legibility of physician handwriting is not as dismal as assumed; physicians can effectively communicate on paper.

Handwriting↗
PubMed1994

Global rating systems used in assessing knee arthroplasty outcomes.

Global, aggregated knee rating systems are commonly used to assess patient outcomes following knee arthroplasty. In this study, the authors performed a systematic literature search and found that 17% of the English-language studies addressing primary knee arthroplasty reported on patient outcomes following the procedure using a standardized global rating system. The authors describe, in detail, the rating systems' development and format. This study found 34 different rating systems represented in the literature from 1972 to 1992. Great variability was found in the rating systems' design and utilization. Additionally, these condition-specific, physician-based rating systems did not have documented studies demonstrating their reliability or validity. Future research will need to address the issues of selecting and aggregating outcome measures and of deriving any necessary weighting schemes. The ability of researchers to compare patient outcomes across studies will be enhanced when there is consistency in reported outcome measures.

Humans↗
PubMed1994

Depression in late life: the use of clinical characteristics to focus screening efforts.

BACKGROUND: The objective of the study was to identify clinical characteristics associated with depressive symptoms in late life so that screening could focus on elderly patients most likely to benefit from further evaluation. METHODS: We used cross-sectional screening for significant symptoms of depression using the Center for Epidemiologic Studies Depression scale and identification of patients' clinical characteristics from patient interviews and a computerized medical record. The setting was an academic primary care group practice at an urban ambulatory care center. Participants were 1,633 consecutively consenting patients aged 60 and older who visited the center between January and August 1991. Mean age was 70 years; 72% were women, 32% were White, 47% had less than 8 years of education, and 7% had no health insurance. RESULTS: There were 251 (15%) patients with significant symptoms of depression. Antidepressants were prescribed to 1 in 7 patients with such symptoms, with amitriptyline being the most commonly prescribed. Bivariate analyses indicated that patients with significant symptoms of depression were more likely to be White, female, without health insurance, and were more likely to have probable alcoholism, mild cognitive loss, and to receive narcotics, histamine H2 antagonists, and/or benzodiazepines. Depressive symptoms were not significantly correlated with age, education, income, or chronic medical conditions. CONCLUSIONS: Significant symptoms of depression were common and correlated with several readily available clinical variables. However, these variables lack sufficient discriminatory power to allow for the selective screening of elderly patients most likely to suffer from symptoms of depression. Thus, formal screening for depression among all elderly patients in primary care may be necessary to improve the recognition of this morbid illness.

Adrenergic beta-Antagonists↗
PubMed1994

Improving treatment of late life depression in primary care: a randomized clinical trial.

OBJECTIVE: Facilitate primary care physicians' compliance with recommended standards of care for late life depression by reducing barriers to recognition and treatment. DESIGN: Randomized controlled clinical trial of physician-targeted interventions. SETTING: Academic primary care group practice caring for an urban, medically indigent patient population. PATIENTS/PARTICIPANTS: Patients aged 60 and older who exceeded the threshold on the Centers for Epidemiologic Studies Depression Scale (CES-D) and the Hamilton Depression Rating Scale (HAM-D) and their primary care physicians. INTERVENTION: Physicians of intervention patients were provided with patient-specific treatment recommendations during 3 special visits scheduled specifically to address the patient's symptoms of depression. In general, physicians were encouraged to establish a diagnosis of depression and educate their patient about the diagnosis, discontinue medications that can cause or exacerbate depressive symptoms, initiate antidepressants when appropriate, and consider referral to psychiatry. Guidelines for prescribing antidepressants were provided. Control physicians received no intervention, and control patients received usual care. MAIN OUTCOME MEASURES: Frequency of recording a depression diagnosis, stopping medications associated with depression, initiating antidepressant medication, and psychiatry referral; mean changes in HAM-D and Sickness Impact Profile (SIP) scores. RESULTS: One hundred three physicians and 175 patients were involved in the clinical trial. Physicians of intervention patients were more likely to diagnose depression and prescribe antidepressants (P < 0.01). There were no differences between the groups in the frequency of stopping medications associated with depression or referrals to psychiatry. Medications with the strongest cause and effect relationship to depression were infrequently used in this cohort of patients. Although both groups showed improvement in HAM-D and SIP scores, we were unable to demonstrate significant differences in HAM-D or SIP scores between the 2 groups. CONCLUSIONS: Intensive screening and feedback of patient-specific treatment recommendations increased the recognition and treatment of late life depression by primary care physicians. However, we were unable to demonstrate significant improvement in depression or disability severity among intervention patients despite the informational support provided to their physicians. Efforts to improve the functional status of these patients may require more integrated interventions and more aggressive attempts to target psychosocial stressors traditionally outside the purview of primary care.

Aged↗
PubMed1994

Tricompartmental knee replacement. A comparison of orthopaedic surgeons' self reported performance rates with surgical indications, contraindications, and expected outcomes. Knee Replacement Patient Outcomes Research Team.

The chance of a person with osteoarthritis of the knee receiving a knee replacement is highly variable. To understand better the reasons for this variation, all practicing orthopaedists in Indiana were surveyed about their management of severe knee osteoarthritis and their perception of tricompartmental knee replacement as a therapeutic option. Their perceptions of indications and outcomes of knee replacement were compared with the self reported annual number of patients for whom they performed (or referred to other surgeons for) tricompartmental knee replacements. A completed survey was returned by 220 (79%) of the 280 orthopaedists surveyed; analyses were limited to the 188 respondents who had cared for at least one patient with osteoarthritis of the knee in the prior 2 weeks (mean = 13). These surgeons reported performing (or referring patients for) a mean of 31 knee replacements in the prior year (SD 45, median 21, range 0-480 knee replacements). There was strong agreement (> 95%) among respondents for seven (21%) of 33 surgical indications and contraindications, and more general agreement (> 60%) for 21 (64%). In the five factors (15%) for which there was disagreement, there was no consistent relationship between opinions and self reported knee replacement performance rate. Surgeons reporting more knee replacements had significantly higher estimates of pain relief and functional improvement following surgery, and lower estimates of prosthesis infection and failure rates. When all responses were considered together, four decision factors correlated independently with the performance of more knee replacements, but these four factors explained only 24% of the variation in self reported knee replacement performance.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Requiring physicians to respond to computerized reminders improves their compliance with preventive care protocols.

OBJECTIVE: To improve compliance with computer-generated reminders to perform fecal occult blood testing (FOBT), mammography, and cervical Papanicolaou (Pap) testing. DESIGN: Six-month prospective, randomized, controlled trial. SETTING: Academic primary care general internal medicine practice. SUBJECTS: Thirty-one general internal medicine faculty, 145 residents, and 5,407 patients with scheduled visits who were eligible for any of the three cancer screening protocols. INTERVENTION: Primary care teams of internal medicine residents and faculty received either routine computer reminders (control) or the same remainders to which they were required to circle one of four responses: 1) "done/order today," 2) "not applicable to this patient," 3) "patient refused," or 4) "next visit." RESULTS: Intervention physicians complied more frequently than control physicians with all remainders combined (46% vs 38%, respectively, p = 0.002) and separately with remainders for FOBT (61% vs 49%, p = 0.0007) and mammography (54% vs 47%, p = 0.036) but not cervical Pap testing (21% vs 18%, p = 0.2). Intervention residents responded significantly more often than control residents to all reminders together and separately to reminders for FOBT and mammography but not Pap testing. There was no significant difference between intervention and control faculty, but the compliance rate for control faculty was significantly higher than the rate for control residents for all reminders together and separately for FOBT but not mammography or Pap testing. The intervention's effect was greatest for patients > or = 70 years old, with significant results for all tests, together and singly, for residents but not faculty. Intervention physicians felt that the reminders were not applicable 21% of the time (due to inadequate data in patient's electronic medical records) and stated that their patients refused 10% of the time. CONCLUSIONS: Requiring physicians to respond to computer-generated reminders improved their compliance with preventive care protocols, especially for elderly patients for whom control physicians' compliance was the lowest. However, 100% compliance with cancer screening remainders will be unattainable due to incomplete data and patient refusal.

Adult↗
PubMed1992

Principles of pharmacoeconomic analysis of drug therapy.

Economic analyses have become increasingly important in healthcare in general and with respect to pharmaceuticals in particular. If economic analyses are to play an important and useful role in the allocation of scarce healthcare resources, then such analyses must be performed properly and with care. This article outlines some of the basic principles of pharmacoeconomic analysis. Every analysis should have an explicitly stated perspective, which, unless otherwise justified, should be a societal perspective. Cost minimisation, cost-effectiveness, cost-utility and cost-benefit analyses are a family of techniques used in economic analyses. Cost minimisation analysis is appropriate when alternative therapies have identical outcomes, but differ in costs. Cost-effectiveness analysis is appropriate when alternative therapies differ in clinical effectiveness but can be examined from the same dimension of health outcome. Cost-utility analysis can be used when alternative therapies may be examined using multiple dimensions of health outcome, such as morbidity and mortality. Cost-benefit analysis requires the benefits of therapy to be described in monetary units and is not usually the technique of choice. The technique used in an analysis should be described and explicitly defended according to the problem being examined. For each technique, the method of determining costs is the same; direct, indirect, and intangible costs can be considered. The specific costs to be used depend on the analytical perspective; a societal perspective implies the use of both direct and indirect economic costs. A modelling framework such as a decision tree, influence diagram, Markov chain, or network simulation must be used to structure the analysis explicitly. Regardless of the choice of framework, all modelling assumptions should be described. The mechanism of data collection for model inputs must be detailed and defended. Models must undergo careful verification and validation procedures. Following baseline analysis of the model, further analyses should examine the role of uncertainty in model assumptions and data.

Costs and Cost Analysis↗
PubMed1991

Oral corticosteroid therapy for patients with stable chronic obstructive pulmonary disease. A meta-analysis.

PURPOSE: To evaluate the effectiveness of oral corticosteroid therapy in patients with stable chronic obstructive pulmonary disease. DATA IDENTIFICATION: An English-language literature search using MEDLINE (1966 to 1989) and a bibliographic review of all retrieved articles identified 33 original studies of oral corticosteroid use in chronic obstructive pulmonary disease published since 1951. STUDY SELECTION: We submitted a photocopy of each study's "methods" section to three nonstudy physician-investigators who used nine explicit criteria to independently assess study quality. Ten studies met all criteria and five studies met some of the criteria. DATA EXTRACTION: To compare outcomes across all qualifying studies, we defined response to therapy as a 20% or greater increase in the baseline forced expiratory volume in 1 second (FEV1); we defined the treatment effect size for each study as the proportion of patients who responded to corticosteroid therapy minus the proportion of patients who responded to placebo. Potential confounding variables as related to eligibility criteria and treatment protocols were also assessed for each study. RESULTS OF DATA SYNTHESIS: Among ten studies that met all nine criteria, we found no significant differences in eligibility criteria, treatment protocol, or study design. No association was found between treatment effect size and publication date, study size, mean patient age, or FEV1. These studies had reported effect sizes ranging from 0% to 56%; we calculated a weighted mean effect size of 10% (95% CI, 2% to 18%). When studies meeting only some of the criteria were included in the calculation, the weighted mean effect size was 11% (95% CI, 4% to 18%). CONCLUSIONS: Patients with stable chronic obstructive pulmonary disease receiving oral corticosteroid therapy have a 20% or greater improvement in baseline FEV1 approximately 10% more often than similar patients receiving placebo.

Administration, Oral↗
PubMed1990

Flexible sigmoidoscopy plus air contrast barium enema versus colonoscopy for suspected lower gastrointestinal bleeding.

A randomized, controlled trial was performed to compare the diagnostic yields and cost-effectiveness of two strategies for the evaluation of nonemergent lower gastrointestinal bleeding. Three hundred eighty patients aged greater than or equal to 40 yr were randomized to undergo initial flexible sigmoidoscopy plus air contrast barium enema or colonoscopy; 332 completed the initial studies. Initial colonoscopy detected more cases of polyps less than 9 mm in size, adenomas, and arteriovenous malformations but fewer cases of diverticulosis. No significant difference was found between strategies in the number of patients detected with cancers or polyps greater than or equal to 9 mm in size. In both strategies, cancers were more common in subjects aged greater than or equal to 55 yr (8% overall) than in those aged less than 55 yr (1%). Among patients aged less than 55 yr with suspected lower gastrointestinal bleeding, initial flexible sigmoidoscopy plus air contrast barium enema is a more cost-effective strategy for the detection of colonic neoplasms than initial colonoscopy. However, initial colonoscopy is more cost effective for those aged greater than or equal to 55 yr.

Barium Sulfate↗
PubMed1989

Quantifying uncertainty in medical decisions.

Effective handling of uncertainty is one of the central problems in medical decision making. The sources and effects of uncertainty in medical decision making are examined and some new quantitative approaches for solving the associated problems are outlined. To handle uncertainty in the branching probabilities and node utilities for probability trees representing alternative treatment strategies, a public domain software package that can be used for the construction, analysis and comparison of probability trees with random parameters was developed. To facilitate specification of the random variables that arise in medical decision making problems, public domain software packages for both data-driven and subjective estimation of probability densities from the Johnson translation system of distributions have also been developed. For the analysis of complex problems that cannot be adequately represented by probability trees or by simple stochastic processes such as Markov chains, network simulation approaches that are oriented toward the sequence of activities seen by individual patients in the course of treatment are described.

Computer Simulation↗
PubMed1989

Unsuspected pulmonary tuberculosis in a community teaching hospital.

Tuberculosis remains a significant clinical and public health problem in the United States. To determine if a significant proportion of hospitalized patients diagnosed as having pulmonary tuberculosis were not suspected of the disease following initial patient assessment, we retrospectively reviewed the microbiology records of a 515-bed community teaching hospital and identified all patients with culture-proven Mycobacterium tuberculosis infection hospitalized between January 1983 and December 1987. Pulmonary tuberculosis was not suspected in 13 (42%) of 31 patients with active disease. These patients were elderly (92% aged 65 years or older vs 8% aged less than 65 years), had a delay in respiratory isolation (6 vs 1 days) and diagnosis (8 vs 3 days), in addition to a longer hospitalization (16 vs 11 days) with increased mortality (46% vs 11%). Inadequate diagnosis may contribute to the persistence of morbidity and mortality from tuberculosis in this country.

Adult↗