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At least 1,387 records · Page 77Linked to original sources
PubMed2003

Compliance to the prescribed dose and overall treatment time in five randomized clinical trials of altered fractionation in radiotherapy for head-and-neck carcinomas.

PURPOSE: To investigate compliance to the prescribed dose-fractionation schedule in five randomized controlled trials of altered fractionation in radiotherapy for head-and-neck carcinoma. METHODS AND MATERIALS: Individual patient data from 2566 patients participating in the European Organization for Research and Treatment of Cancer (EORTC) 22791, EORTC 22811, EORTC 22851, Princess Margaret Hospital (PMH), and continuous hyperfractionated accelerated radiotherapy (CHART) head-and-neck trials were merged in the fractionation IMPACT (Intergroup Merger of Patient data from Altered or Conventional Treatment schedules) study database. The ideal treatment time was defined as the minimum time required to deliver a prescribed schedule. Compliance to the prescribed overall treatment time was quantified as the difference between the actual and the ideal overall time. An overall measure of compliance in an individual patient, the total dose lost (TDL), was calculated as the dose lost due to prolongation of therapy (assuming a D(prolif) of 0.64 Gy/day) plus the difference between the prescribed and the actual dose given. RESULTS: The time in excess of the ideal ranged up to 97 days (average 3.9 days), and 25% of the patients had delays of 6 days or more. World Health Organization (WHO) performance status and nodal stage had a significant effect on TDL. TDL was significantly higher in the conventional than in the altered arm of the EORTC 22851 and CHART trials. In the PMH trial, TDL was significantly higher in the hyperfractionation than in the conventional arm. Centers participating in the three EORTC trials varied significantly in their compliance. There was a significant improvement in compliance in patients treated more recently. CONCLUSIONS: Even in randomized controlled trials, compliance to the prescribed radiation therapy schedule may be relatively poor, especially after conventional fractionation. This affects the interpretation of the outcome of these trials.

Dose Fractionation, Radiation↗
PubMed2001

The effects of a pharmacy-based intervention on the knowledge and attitudes of asthma patients.

The effects of a pharmacy-based intervention on the knowledge and attitudes of asthma patients was studied with a small convenience sample in four Finnish community pharmacies. The intervention consisted of patient education, counselling and outcomes monitoring according to Therapeutic Outcomes Monitoring (TOM) concept. Twenty-eight patients aged 20-64 years suffering from asthma and having problems in asthma management were involved. Measurements were done at baseline, immediately after the intervention (12 months) and 1 year after the intervention (24 months) using a pre/post-test design, with the patients being their own controls. Both knowledge about and attitudes towards asthma as a disease improved significantly during the intervention. Also knowledge about medication improved significantly during the intervention, though the patients' attitudes towards the medication remained unchanged. The negative correlation between knowledge about and attitudes towards asthma (-0.35) at baseline disappeared after the intervention (0.21). There was a positive correlation between knowledge about and attitudes towards medication at 12 months (0.40, P=0.04) which was still significant 1 year after the intervention (0.40, P=0.04).

Adult↗
PubMed2004

Increasing knowledge about a screening test: preliminary evaluation of a structured, chart-based, screener presentation.

The provision and understanding of good quality information is one of the key characteristics of an informed choice. However, written materials alone often fail to achieve good understanding of screening tests. The present study describes the preliminary evaluation of a structured, chart-directed presentation, aimed at increasing knowledge of a screening test. Forty mothers of babies undergoing a newborn hearing test received either a standard, or a standard plus structured, presentation of the screening test. Standard presentation was a leaflet and short verbal explanation of the test. Structured presentation comprised an illustrated chart explaining the process and possible outcomes of screening, followed by screeners checking mothers understanding of key points and, if necessary, giving further explanation. After screening, maternal knowledge of the test was assessed using seven multiple choice items. Overall knowledge was high. For women with lower levels of education, the structured presentation resulted in significantly higher levels of knowledge than the standard presentation only.

Adult↗
PubMed2000

A reliable and valid asthma general knowledge questionnaire useful in the training of asthma educators.

Using the responses of 115 adults attending an asthma educator training course, the Asthma General Knowledge Questionnaire for Adults (AGKQA) was found to be an acceptably valid and reliable measure for assessing knowledge related to the management of asthma by adults. Content and face validity: expert assessors considered the AGKQA to be a relevant and plausible test of the asthma general knowledge content of the programme. Criterion-related validity: the pretraining scores of educators were significantly higher (P < 0.001) than those of adults with no experience of asthma; total scores for the AGKQA and an asthma knowledge questionnaire developed for parents of children with asthma correlated strongly, 0.72. Test-retest reproducibility: the Spearman rank correlation for the test-retest score was 0.72 (P < 0.02), kappas for concordance of item responses were moderate to very good for two thirds of the items. Internal consistency for the total scale was also acceptable, KR20 0.66.

Adolescent↗
PubMed2002

Pharmacoeconomic evaluation of a patient education letter aimed at reducing long-term prescribing of benzodiazepines.

OBJECTIVE: To determine the economic implications of sending an educational letter to patients, aimed at reducing long-term BDZ prescribing. METHOD: Letters were sent to 242 patients from 2 general medical practices. BDZ usage and costs were compared in the years before and after intervention using numbers of defined daily dosages (DDDs) prescribed. The cost of intervention implementation was estimated using pharmacist, GP and administrative staff time, plus postage costs. MAIN OUTCOME MEASURES: Number of BDZ DDDs prescribed during the 12-month periods before and after intervention. The cost implications of intervention. RESULTS: Mean patient age was 67 years, 75% were female and the mean duration of BDZ usage was 19 years. A mean of 337 benzodiazepine DDDs per patient were prescribed during the baseline year. Overall BDZ usage at baseline was increasing by 13%. After receiving the letter, 31% of patients discussed BDZ usage with their GP and 10% had their drug or strength changed. During the year after intervention, a significant reduction of 17% in benzodiazepine usage was observed compared to baseline; 5% of patients ordered no more benzodiazepine prescriptions after receiving the letter. Mean BDZ costs reduced by 1.20 Pounds per patient after intervention. The cost of intervention implementation was 5.54 Pounds per patient, giving a net cost of 4.34 Pounds per patient, or 86.80 Pounds to obtain one BDZ discontinuation. CONCLUSION: This intervention is effective, simple, and inexpensive. Its minimal cost could be justified given the morbidity associated with the long-term prescribing of benzodiazepines, particularly in the elderly.

Adult↗
PubMed2002

Effect of eptifibatide for acute coronary syndromes: rapid versus late administration--therapeutic yield on platelets (The EARLY Platelet Substudy).

BACKGROUND: Receptors other than GP IIb/IIIa may mediate leukocyte-platelet-endothelial interactions that obstruct the microvasculature in acute coronary syndromes (ACS) and cause microinfarcts. The effect of eptifibatide on these receptors was investigated in a substudy of the EARLY Trial. METHODS: Patients received early (in the Emergency Department, n = 27) or late (12-24 h, n = 28) eptifibatide. Ten platelet receptors by flow cytometry and platelet aggregation (10 micromol/L ADP) were measured serially at baseline, and at 3, 6, 12 and 24 h after randomization. RESULTS: Platelet aggregation was rapidly inhibited by early eptifibatide therapy (baseline, 72 +/- 20%; 3 h post, 7 +/- 9%; p < 0.001). No significant differences were seen in either group for CD 31, CD 63, CD 107a, CD 107b, CD 41 (GPIIb/IIIa expression), or CD 62p. Leukocyte-platelet aggregate formation (mean fluorescense intensity) trended upward after presentation (early baseline, 43.1 +/- 26.0 versus 65.8 +/- 35.6, p =.09). PAC-1 (GP IIb/IIIa activity), CD 51/61 (vitronectin receptor) and CD 42b (GP Ib) were inhibited by eptifibatide (p <.05). CONCLUSIONS: In Emergency Department patients with unstable angina, early eptifibatide rapidly and profoundly inhibits platelet aggregation and reduces GP IIb/IIIa activity and the expression of CD51/61 and CD 42b; the latter two effects may also contribute to the drug's anti-thrombotic effect. However, platelet-leukocyte aggregate formation, a marker of platelet activity rises within 24 h after presentation despite eptifibatide therapy and is a potential mechanism for microvascular obstruction.

Acute Disease↗
PubMed2000

Nonparametric tests for stratum effects in the Cox model.

This paper considers the stratified proportional hazards model with a focus on the assessment of stratum effects. The assessment of such effects is often of interest, for example, in clinical trials. In this case, two relevant tests are the test of stratum interaction with covariates and the test of stratum interaction with baseline hazard functions. For the test of stratum interaction with covariates, one can use the partial likelihood method (Kalbfleisch and Prentice, 1980; Lin, 1994). For the test of stratum interaction with baseline hazard functions, however, there seems to be no formal test available. We consider this problem and propose a class of nonparametric tests. The asymptotic distributions of the tests are derived using the martingale theory. The proposed tests can also be used for survival comparisons which need to be adjusted for covariate effects. The method is illustrated with data from a lung cancer clinical trial.

Humans↗