Subcortical afferents to the frontal lobe in the rhesus monkey studied by means of retrograde horseradish peroxidase transport.
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Animals↗
Biomedical subjects
J Kievit
Publications and source records attributed to J Kievit.
Basal forebrain and hypothalamic connection to frontal and parietal cortex in the Rhesus monkey.
Horseradish peroxidase was injected in different parts of the frontal and parietal cortex in 17 rhesus monkeys. In all cases the enzyme was transported retrogradely to neurons in the substantia innominata and hypothalamus as well as in the thalamus. These new findings demonstrate that these cortical areas receive direct afferent fibers from limbic basal forebrain areas concerned with emotion and motivation.
Animals↗
Retrograde axonal transport of horseradish peroxidase in rats forebrain.
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Animals↗
Best medical practice in The Netherlands: a decision analyst's view.
Opinions over what is bad, good and best medical practice have varied through time. In older days, medicine aimed exclusively at maximum effectiveness through an aggressive diagnostic and therapeutic approach, irrespective of cost considerations. Budget constraints in health care have put limits on this exhaustive form of medicine. Consequently, considerations regarding the ratio between the quality and the cost of medical care are becoming more and more important in the definition of 'best medical practice'. Quality standards in medicine thus should not be based exclusively on medical considerations, but should also take cost considerations into account. This balanced integration of quality and cost represents a new challenge in medicine. It demands an active interest and participation of the medical profession in budget affairs, and close cooperation between health care professionals, health economists, and health care administrators. If this integration is done explicitly and quantitatively, it requires the use of decision analysis and cost-effectiveness analysis techniques. Recent experiments at the department of Surgery at the Leiden University Hospital have demonstrated the feasibility of this approach. Quality standards were set by means of explicit outcome criteria, and policy changes were executed on the basis of cost-effectiveness analysis. Quality of care could be maintained at the same or higher levels while cost savings of up to 60% were realized. The advance of 'best medical practice' in the present and future requires a multidisciplinary approach to medicine, that is best realized by the use of explicit and quantitative quality standards. This approach can only be successful if close cooperation between professionals, administrators, economists and politicians in health care can be realized.
Decision Support Techniques↗
Preoperative diagnostic tests for operable thyroid disease.
Although the availability and acceptance of fine-needle aspiration biopsy (FNAB) of thyroid nodules has increased, many physicians still use thyroid scintigraphy for distinguishing benign from malignant lesions. We evaluated these diagnostic tests in 350 patients who had thyroid surgery in our institution between 1977 and 1990. Histologic confirmation of FNAB was obtained in 265 patients. In the group of patients having surgery, 247 thyroid scintigraphies were performed. Our patients were divided into two groups (1977-1986 and 1986-1990). The first group comprised 173 patients with 173 FNABs and 126 scintigrams. The second group consisted of 177 patients having 92 FNABs and 121 scintigrams. Results of scintigrams were analyzed in the second group only. In 5 out of 120 cases where the FNAB result was "benign or probably benign" the lesion appeared to be malignant postoperatively. If the FNAB result was "malignant or probably malignant" (n = 83) the pathology report confirmed a malignancy in 68 cases (81.9%). In 56 instances of all 265 FNABs the cytology report was not conclusive ("uncertain"); in 21.4% of these cases a malignancy was found postoperatively. An FNAB-result "(probably) malignant" had a positive predictive value of 0.819 while the negative predictive value of a result "(probably) benign" is 0.950. An "uncertain" result does not take away our concern so this result should have the same consequences as those of a result "(probably) malignant". In that case, FNAB-sensitivity is 93.0% and specificity 66.1%. Eighty-five of the last 116 scintigraphies showed a solitary node. Eleven of these nodes were hot while 74 were cold.(ABSTRACT TRUNCATED AT 250 WORDS)
Adolescent↗
Endocrine-metabolic response to abdominal aortic surgery: a randomized trial of general anesthesia versus general plus epidural anesthesia.
The influence of epidural anesthesia on the endocrine-metabolic response following abdominal aortic reconstruction was studied in a prospective randomized trial. Cortisol and catecholamine responses and nitrogen balance were measured in two groups of five patients receiving general anesthesia only (group 1) or general anesthesia combined with epidural bupivacaine (group 2). The study lasted from preoperatively until the first postoperative day. At 2100 hours on the day of surgery serum cortisol concentrations were higher in group 1 than in group 2 (1.41 versus 0.82 mumol/L; p < 0.01). Likewise the total perioperative hypercortisolemia, expressed as the area under the curve, was significantly higher in group 1 (11.7 versus 5.7 mumol/L/hr, p < 0.01). Intraoperative urinary excretion of epinephrine and postoperative norepinephrine excretion were significantly higher in group 1 than in group 2. Urinary excretion of free cortisol and cumulative nitrogen balance were not different between the groups. Although the number of patients was limited and the sensory nerve block level was not measured perioperatively, this study suggests that epidural anesthesia attenuates the stress response to aortic surgery.
Aged↗
Detection of recurrence after surgery for colorectal cancer.
Of all patients operated for colorectal cancer, 1 in 3 will suffer from cancer recurrence, and most of these patients will die from disseminated disease. Postoperative follow-up aims at improving these grim figures. This sound idea has not been supported by any empirical data. In the current article, we discuss some theoretical issues concerning colorectal cancer follow-up, and present results of a cost-effectiveness analysis, used to model the natural history of colorectal cancer recurrence and the costs and effects of follow-up and re-operation. The expected results of three policies were calculated: no follow-up, selective follow-up and intensive follow-up. For most patients, follow-up will only lead to a significant increase in costs, without increase in (quality-adjusted) life expectancy. Colorectal cancer follow-up is not "evidence-based medicine".
Age Factors↗
Unstable preferences: a shift in valuation or an effect of the elicitation procedure?
OBJECTIVE: Many studies suggest that impaired health states are valued more positively when experienced than when hypothetical. This study investigated to what extent this discrepancy occurs and examined four possible explanations: non-corresponding description of the hypothetical health state, new understanding due to experience with the health state, valuation shift due to a new status quo, and instability of preference. PATIENTS AND METHODS: Fifty-five breast cancer patients evaluated their actually experienced health state, a radiotherapy scenario, and a chemotherapy control scenario before, during, and after postoperative radiotherapy. Utilities were elicited by means of a visual analog scale (VAS), a chained time tradeoff (TTO), and a chained standard gamble (SG). RESULTS: The discrepancy was found for all methods and was statistically significant for the TTO (predicted utilities: 0.89, actual utilities: 0.92, p < or = 0.05). During radiotherapy, significant differences (p < or = 0.01) were found between the utilities for the radiotherapy scenario and the actual health state by means of the VAS and the SG, suggesting non-corresponding description as an explanation. The utilities of the radiotherapy scenario and the chemotherapy control scenario remained stable over time, and thus new understanding, valuation shift, and instability could be ruled out as explanations. CONCLUSION: Utilities obtained through hypothetical scenarios may not be valid predictors of the value judgments of actually experienced health states. The discrepancy in this study seems to have been due to differences between the situations in question (non-corresponding descriptions).
Adult↗
Stability of patients' preferences for chemotherapy: the impact of experience.
BACKGROUND: Studies have shown that utilities for a particular treatment, elicited by means of a hypothetical treatment scenario, may remain stable within the same patients when examined before, during, and after experiencing that treatment (within-group stability). However, other studies have found that utilities for a particular health state may differ between patient groups who are and who are not experiencing the particular health state (between-group differences). OBJECTIVE: The authors evaluated this apparent contradiction in the case of adjuvant chemotherapy for breast cancer. A related purpose was to examine whether a chemotherapy scenario adequately reflects the patients' own experiences with chemotherapy. METHOD: Forty-three patients with early-stage breast cancer evaluated their actually experienced health state and a chemotherapy scenario before, during, and after undergoing adjuvant chemotherapy (chemotherapy group). A control group of 51 patients for whom chemotherapy was not part of the treatment plan was interviewed at similar points in time. Utilities were elicited by means of a visual analog scale (VAS), a chained time trade-off (TTO), and a chained standard gamble (SG). RESULTS: The utilities for the chemotherapy scenario remained relatively stable over time in the 2 patient groups. Furthermore, the chemotherapy scenario was evaluated more positively by patients in the chemotherapy group than by control patients (e.g., utilities before chemotherapy: VAS 0.69 vs. 0.50, TTO 0.88 vs. 0.50, SG 0.92 vs. 0.58, all Ps < 0.01). Finally, patients in the chemotherapy group evaluated their actually experienced health states during chemotherapy higher than the chemotherapy scenario that was assessed at the same time (VAS 0.79 vs. 0.69, TTO 0.93 vs. 0.87, SG 0.97 vs. 0.96, all Ps < 0.05). CONCLUSIONS: Both within-group stability and between-group differences were found. A possible explanation for within-group stability may be that the chemotherapy scenario did not fully correspond to the patients' actual experiences with chemotherapy ("noncorresponding description"). Therefore, preferences did not change even when the patients' own clinical health status had changed. The between-group differences may be explained by "anticipated adaptation." Both explanations may work together to explain why utilities remain stable within the same patients but differ between different patient groups.
Adult↗
Test-retest reliabilities of two treatment-preference instruments in measuring utilities.
The authors assessed the test-retest reliabilities of two treatment-preference instruments recently applied to the measurement of the utilities of health states after different treatment modalities for cancer. The first instrument measures the strengths of preferences concerning a choice between a wait-and-see policy, and treatment with radiotherapy after an initial surgical breast-conserving procedure for early breast cancer. The second measures the strengths of preferences concerning a choice between two hypothetical surgical treatment outcomes in cancer of the rectum with different probabilities of expected five-year survival. Both measure the strength of a subject's treatment preference given probabilities of treatment-related costs and benefits. The subjects were radiotherapy technicians (n = 20) and cancer patients (n = 20) who were interviewed in weeks 2 and 4 of radiotherapy. The test-retest reliabilities of both instruments were inconsistent and moderately high, with Spearman's rank correlations ranging from 0.38 to 0.81 and weighted kappas ranging from 0.38 to 0.69. To investigate whether the start of treatment with radiotherapy influenced the utilities that patients assigned to health states, the same procedure was applied in another, comparable, group of patients with cancer (n = 20). For this group, the first assessment was made prior to the start of treatment and the second during the second week of radiation therapy. The scores of this group of patients indeed appeared to be less stable than the scores of the patients assessed in weeks 2 and 4 of radiotherapy. However, the instability of the scores could have been the result of test bias.
Adult↗
Using age-specific rates in a Markov model.
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Adult↗
Utility assessment in cancer patients: adjustment of time tradeoff scores for the utility of life years and comparison with standard gamble scores.
The standard gamble (SG) and the time tradeoff (TTO), two frequently used methods of utility assessment, have often been found to lead to different utilities for the same health state. The authors investigated whether adjustment of TTO scores for the utility of life years (risk attitude) eliminated this difference. In addition, the association between risk attitude and sociodemographic and medical variables was studied. In 30 disease-free testicular cancer patients, SG and TTO were used to assess the utilities of four health profiles relevant to testicular cancer. Utility of life years was estimated from certainty equivalents (CEs). SG scores were significantly higher than unadjusted TTO scores for all profiles. As the majority of patients (85%) were risk-averse, CE-adjusted TTO scores were higher than unadjusted scores, and were not significantly different from those obtained from the SG for three of the four profiles. However, adjusted scores were still slightly but consistently lower than SG scores. Possible explanations for this discrepancy are discussed. An association was found between risk aversion and medical treatment: patients who had received chemotherapy for their cancers were more risk-averse than were patients who had been in a surveillance protocol only. As risk aversion can have an impact on treatment decisions, it is important to assess the risk posture of the patient to whom the decision pertains.
Adult↗
Tradeoffs between quality and quantity of life: development of the QQ Questionnaire for Cancer Patient Attitudes.
The patient's perspective is of prime concern in weighing the benefits and side effects of oncologic treatment. Little is known about patients' preference and attitudes. The authors developed a short questionnaire to assess patient attitudes concerning trade-offs between quality of life and length, or quantity, of life (the QQ Questionnaire). The questionnaire turned out to be feasible for use in various groups of cancer patients. In a factor analysis, the questionnaire was shown to consist of two factors, a Q(uality) and a L(ength) factor. Values of Cronbach's alpha for the Q and L scales (consisting of four items each) were 0.68 and 0.79, respectively. Younger patients and patients who have children assigned relatively more importance to striving for prolonged survival. Contrary to our expectation, no association was found between scores on the two scales and time tradeoff utility scores. The QQ Questionnaire can be used in research settings to study patient attitudes and the stability and determinants of patients' preferences.
Adult↗
Patients' utilities for cancer treatments: a study of the chained procedure for the standard gamble and time tradeoff.
OBJECTIVE: Temporary health states cannot be measured in the traditional way by means of techniques such as the time tradeoff (TTO) and the standard gamble (SG), where health states are chronic and are followed by death. Chained methods have been developed to solve this problem. This study assesses the feasibility of a chained TTO and a chained SG, and the consistency and concordance between the two methods. PATIENTS AND METHODS: Seventy female early-stage breast cancer patients were interviewed. In using both chained methods, the temporary health state to be evaluated was weighed indirectly with the aid of a temporary anchor health state. The patients were asked to evaluate their actual health states, a hypothetical radiotherapy scenario, and a hypothetical chemotherapy scenario. RESULTS: Sixty-eight patients completed the interview. The use of the anchor health state yielded some problems. A significant difference between the means of the TTO and the SG was found for the anchor health state only. For the other health states, the results were remarkably close, because the design avoided some of the bias effects in traditional measurements. CONCLUSION: The feasibility and the consistency of the chained procedure were satisfactory for both methods. The problems regarding the anchor health state can be solved by adapting the methods and by the use of a carefully chosen anchor health state. The chained method avoids biases present in the conventional method, and thereby the TTO and the SG may be reconciled. Moreover, there are several psychological advantages to the method, which makes it useful for diseases with uncertain prognoses.
Adult↗
Multiattribute utility scores for predicting family physicians' decisions regarding sinusitis.
To examine whether multiattribute utility (MAU) scores can be used to predict family physicians' decisions regarding patients suspected to have sinusitis and rhinitis, 100 randomly selected family physicians from the Leiden area (The Netherlands) were asked to rank a set of six attributes regarding their importance, yielding attribute weights. Next, the physicians were asked to rate the degrees to which five decision alternatives optimized each attribute, yielding utilities, regarding three case vignettes about a patient suspected to have acute maxillary sinusitis and rhinitis, with a brief clinical history. By combining attribute weights and utilities, a MAU score was calculated for each decision alternative regarding each case vignette. Finally, for each case vignette the physicians' treatment preferences were assessed by means of an open-ended question. For the clear-cut sinusitis case, management strategies and highest MAU scores were concordant for 80% of the physicians. Regarding the dubious sinusitis and rhinitis case, concordance was 50%. The latter was associated with small differences in values between the highest MAU scores. Because agreement among the physicians regarding the management strategies and weight ranks was high and there was little variation in the highest MAU scores, the kappas between the reported management strategies and weight ranks were poor (0.24 and lower). It is concluded that MAU scores may be used to predict family physicians' decisions regarding the management of patients suspected of having sinusitis where there are significant differences in values between the highest MAU scores.
Adult↗
On the use of a hospital information system in evaluating clinical care: a case report.
In this paper we describe, as an example, how we obtained the information needed to evaluate a newly introduced protocol for ordering X-rays for ankle trauma patients. Extensive use was made of available data and facilities of the hospital information system (HIS). Procedures for collecting the required additional data, which were not recorded in the HIS but were needed to evaluate the protocol, were embedded in the current medical and administrative routine of the emergency room. These additional data were also stored in the HIS. Periodically all data were downloaded to a personal computer to analyse the impact of using the protocol on quality of care and costs. In total 1241 patients entered the study, and for 1149 patients a complete dataset was obtained. The sensitivity and specificity of the protocol at the threshold value which was used during the initial study period was 0.77 and 0.80. The reduction in the number of ankle X-rays due to the protocol was significant when compared with a strategy of ordering an X-ray for every ankle trauma patient visiting the emergency room.
Ankle Injuries↗
Analysis of post-operative hypalbuminaemia: a clinical study.
OBJECTIVE: Analysis of severity, causes and relevance of hypalbuminaemia developing after surgery. SUBJECTS: Patients undergoing elective aortic surgery (n = 11) or minor extra-abdominal surgery (n = 6). METHODS: Serum albumin concentration, blood loss, nitrogen balance and complications were determined until the fifth post-operative day. The contributions of haemodilution, albumin loss, albumin catabolism and redistribution were calculated using existing formula. The relation of hypalbuminaemia to the endocrine-metabolic response was determined. RESULTS: Significant hypalbuminaemia occurred after aortic surgery, in the absence of significant complications. No haemodilution occurred. Analysis indicated that 18% of hypalbuminaemia was caused by blood loss. Only 6% could be attributed to albumin catabolism, despite a significant correlation with the endocrine-metabolic response. Seventy-seven percent of hypalbuminaemia was attributed to albumin redistribution. No hypalbuminaemia occurred after minor surgery. CONCLUSION: Post-operative hypalbuminaemia is a normal finding early after aortic surgery. It is mainly caused by albumin redistribution, not by metabolic changes.
Abdomen↗
Psychological effects of routine follow up on cancer patients after surgery.
OBJECTIVES: To assess the subjective value that patients with cancer place on regular follow up after operation; to see what effects regular follow up visits have on the patient's physical and psychological wellbeing; and to find out which variables influence patients wellbeing and attitudes to follow up. DESIGN: Survey by questionnaire. SETTING: University Hospital Leiden, the Netherlands. SUBJECTS: 127 Patients who had been operated on for cancer. INTERVENTIONS: 67 Patients were assessed one month before a routine follow up visit, and 60 on the day of the follow up; 46 of the second group were assessed again two weeks later. MAIN OUTCOME MEASURES: Answers to questions about physical and psychological wellbeing. RESULTS: Most patients were in favour of regular follow up visits at the hospital, and thought that the advantages outweighed the disadvantages. There were more reports of psychological than physical distress one month beforehand, but these were significantly less two weeks after the appointment compared with one month before (p = 0.003) and on the day of the appointment (p < 0.001). Regular follow up visits do not temporarily increase physical or psychological distress; rather there is a temporary decrease, less fear of recurrence, and less perception of any disadvantages. Women in general, and those with breast cancer in particular and patients with a lower educational standard in particular, had significantly more psychological complaints. CONCLUSIONS: Regular follow up visits are in general welcomed by patients who have had operations for cancer.
Adult↗