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At least 1,243 records · Page 69Linked to original sources
PubMed2004

Evaluation of a hospital-based community liaison pharmacy service in Northern Ireland.

OBJECTIVE: To evaluate the impact of a hospital based community liaison pharmacy service on a range of outcomes in patients aged more than 55 years and taking more than 3 prescribed drugs, who had been admitted to the medical unit of a district general hospital in Northern Ireland. METHODS: Having recruited 243 patients, a total of 162 patients completed the full protocol (81 randomly assigned to intervention and 81 to control; mean age of control patients 75 years; mean age of intervention patients 73 years). The interventions by the community liaison pharmacist included: preparation of an accurate medication record following a full review of current medication use; medication counselling; provision of a medicines record sheet informing the patient how to take their drugs; provision of a pharmaceutical discharge letter detailing changes made to drug therapy (this was faxed to the patient's GP and community pharmacist on the day of discharge); provision of a Medicines Helpline. RESULTS: The key findings were as follows: problems were identified in 80% of the intervention patients' prescription charts, 49% of which related to drug omissions from the patients' domiciliary prescriptions. The GP practice record was the most accurate (mean error rate 12.6%) while the GP referral letter was the least accurate (mean error rate 47.3%) source of medication information. Drugs patients brought to hospital were also an inaccurate source (mean error rate 44.0%). The intervention group patients, when compared with control patients, had a significant reduction (P = 0.005) in drug mismatch between drugs prescribed at discharge and taken at home, and had a greater knowledge of their drug regimen 10-14 days after discharge (P < 0.001). The vast majority of patients (96%) felt that the provision of a medicine helpline was a useful service. CONCLUSIONS: The study indicated clear benefits from the involvement of a hospital based community liaison pharmacist in achieving seamless pharmaceutical care between the primary and secondary healthcare settings.

Aged↗
PubMed1993

Measurement error masks bipolarity in affect ratings.

For years, affect researchers have debated about the true dimensionality of mood. Some have argued that positive and negative moods are largely independent and can be experienced simultaneously. Others claim that mood is bipolar, that joy and sorrow represent opposite ends of a single dimension. The 3 studies presented in this article suggest that the evidence that purportedly shows the independence of seemingly opposite mood states, that is, low correlations between positive and negative moods, may be the result of failures to consider biases due to random and nonrandom response error. When these sources of error are taken into account using multiple methods of mood assessment, a largely bipolar structure for affect emerges. The data herein speak to the importance of a multi-method approach to the measurement of mood.

Adult↗
PubMed2000

False-positive myeloperoxidase binding activity due to DNA/anti-DNA antibody complexes: a source for analytical error in serologic evaluation of anti-neutrophil cytoplasmic autoantibodies.

Anti-myeloperoxidase antibodies (anti-MPO) are a major type of anti-neutrophil cytoplasmic antibody (ANCA). While evaluating anti-MPO monoclonal antibodies from SCG/Kj mice, we observed several hybridomas that appeared to react with both MPO and DNA. Sera from some patients with systemic lupus erythematosus (SLE) also react with MPO and DNA. We hypothesized that the MPO binding activity is a false-positive result due to the binding of DNA, contained within the antigen binding site of anti-DNA antibodies, to the cationic MPO. Antibodies from tissue culture supernatants from 'dual reactive' hybridomas were purified under high-salt conditions (3 M NaCl) to remove any antigen bound to antibody. The MPO and DNA binding activity were measured by ELISA. The MPO binding activity was completely abrogated while the DNA binding activity remained. The MPO binding activity was restored, in a dose-dependent manner, by the addition of increasing amount of calf-thymus DNA (CT-DNA) to the purified antibody. Sera from six patients with SLE that reacted with both MPO and DNA were treated with DNase and showed a decrease in MPO binding activity compared with untreated samples. MPO binding activity was observed when CT-DNA was added to sera from SLE patients that initially reacted with DNA but not with MPO. These results suggest that the DNA contained within the antigen binding site of anti-DNA antibodies could bind to the highly cationic MPO used as substrate antigen in immunoassays, resulting in a false-positive test.

Animals↗
PubMed1992

A nine-parameter version of the Heligman-Pollard formula.

"In this paper we outline and evaluate a nine-parameter version of the Heligman-Pollard formula. In our applications, using mortality data for five European countries we found that this version provides closer fits to empirical mortality data than the classical eight-parameter formula, thus eliminating a source of systematic error in this latter formula."

Demography↗
PubMed2006

A first step toward cognitive remediation of voices: a case study.

Several studies have shown that source-monitoring errors are related to verbal hallucinations in schizophrenia. An exploratory pilot study has been carried out to investigate the possibility of training patients in how to avoid errors in source-monitoring. One patient with paranoid schizophrenia and persistent thought insertions was trained for 6 hours to use mnemonic techniques to compensate specific deficits in source-monitoring. Results show that the patient was able to improve his performance and maintain the acquired progress at a 1-month follow-up assessment. These preliminary results are interesting for developing a larger controlled study of cognitive remediation of source-monitoring deficits.

Adult↗
PubMed2004

Doctors and nurses estimation of the weight of patients: A preventable source of systematic error.

BACKGROUND: Although accurate determination of body weight is important in the management of the poisoned patient, many patients have their weight estimated rather than formally measured. OBJECTIVE: To determine how good medical staff are at estimating patients*** body weights. METHODS: Medical staff were asked to estimate the weight of six patients on a poisons ward. Estimated and actual patient weights were statistically compared. RESULTS: Medical staff produced a large range of estimated weights for all patients. Patient weight was incorrectly estimated by greater than 10% in 61% of individual estimations. There was poor statistical correlation between actual and estimated weight. CONCLUSIONS: All patients administered medication based on body weight and those treated following an overdose of any substance should have formal body weight determined as part of their standard management.

Acetylcysteine↗
PubMed2003

Cross-cultural sources of measurement error in substance use surveys.

We present an overview of the cross-cultural quality of survey reports of substance use behaviors in the United States. Empirical data from 36 published studies (1977-2003) are examined to evaluate the reliability and validity of substance use reports across cultural groups. In these studies, race/ethnicity are used as proxy indicators of respondent culture. In general, the available research suggests that, with a few exceptions, the quality of survey data on racial and ethnic disparities in substance use is often limited by differential measurement error. A conceptual paradigm is presented to consider a wide range of potential causes for these differences in measurement error that includes two dimensions: emphasis on negative vs. positive behavior patterns, and emphasis on internal vs. external causal factors. These two dimensions yield four potential models that are useful in understanding variations in substance use measurement error: the cultural deficit model, the cultural conflict model, the mainstream conformity model, and the cultural distrust model. Future research should focus on the ability of each of these alternative models to account for cultural variability in the quality of substance use reporting.

Cultural Characteristics↗
PubMed1976

Underreporting of cancer in medical surveys: a source of systematic error in cancer research.

Systematic errors occur in the reports of disease frequency derived from health surveys based on questionnaire interviews. Five hundred and thirty-three persons with clinically and histologically confirmed disease in a case-control study of cancer were interviewed in their homes by carefully trained interviewers using a standardized questionnaire interview schedule. Comparisons of the information obtained by interview about past history of cancer with cancer registry and hospital medical record information about the same people revealed serious underestimates of correct frequency and wide variation in the rates of correct reporting. The findings reported here and elsewhere add support to an essential requirement in medical survey research: the completeness and accuracy of responses in health interview surveys must be verified and the methods of verification must be reported before the results can be interpreted with confidence.

Carcinoma, Squamous Cell↗
PubMed1991

A proposed prototype for identifying and correcting sources of measurement error in classification systems.

Because many raters are generally involved in the implementation of a patient classification system, interrater reliability is always a concern in the development and use of such a system. In this article, a case example is used to demonstrate a prototype for identifying measurement error introduced at each step in the classification process (assessment, creating summary item responses, and use of these responses for categorization) and to illustrate how this identification may lead to error reduction strategies. The methods of analyses included percent agreement, Kappa, and visual inspection of contingency tables displaying interrater responses to assessment items, summary items, and the placement category. The extent to which raters followed instructions was analyzed by comparing their responses with computer-generated responses across the classification steps. In addition, raters were interviewed regarding their use of the system.

Aged↗
PubMed1994

A method for calculating the distribution of pH in tissues and a new source of pH error from the 31P-NMR spectrum.

The true distribution of the pH in tissues can be determined from the in vivo 31P-nuclear magnetic resonance (NMR) spectrum by converting the parts per million (PPM) axis of the pH responsive resonance to pH using the Henderson-Hasselbalch equation. In addition, the intensity axis of the resonance must be divided by the derivative of the Henderson-Hasselbalch equation to correct for the nonlinear relationship between pH and PPM. This nonlinear relationship causes the apparent center of the resonance in PPM to be dependent not only on the center of the pH distribution but also on its width and distance from the pKa, where Ka is the association constant. Therefore, the pH determined from uncorrected spectra may be in significant error, particularly if the pH distribution is distant from the pKa and is broad. The method was applied to the isolated perfused Morris hepatoma 5123C to determine the distribution of intracellular pH (pHi) using resonances from two intracellular compounds. The two resonances did not report the same pHi unless the spectral data were properly corrected. The method should be of interest to anyone interested in pHi.

Animals↗
PubMed1976

Oxygen affinity of human blood in presence of carbon monoxide.

If carbon monoxide is present in the blood, it is necessary to quantitate its effect on apparent O2 affinity in order to properly compute venous PO2 and P50. Ways of doing this are analyzed theoretically. The classical principles of Haldane and of Roughton and Darling are reviewed and simplified. The method of computation of PO2 in the presence of CO as introduced by Forster is shown to be in considerable error. The source of this error is determined. The error produced if the presence of CO is ignored during the computation of P50 is analyzed.

Carbon Monoxide↗
PubMedDate not supplied

Fine needle aspiration biopsy of Hashimoto's thyroiditis. Sources of diagnostic error.

OBJECTIVE: To determine the accuracy of cytologic interpretation in the diagnosis of Hashimoto's thyroiditis (HT). STUDY DESIGN: At Ottawa Hospital from 1987 to 1994, 1,638 fine needle aspiration biopsies (FNABs) from thyroid were performed. HT was suggested in 184 FNAB samples taken from 157 patients. Of the 184 aspirates diagnosed with HT, 39 had corresponding surgical specimens taken from 31 patients. A retrospective review of these FNABs and surgical pathology slides formed the basis of this study. RESULTS: In 27 (69%) aspirates, HT was diagnosed on both the FNAB and surgical specimens. In 10 of 27 FNABs an associated lesion was not sampled by FNAB. In four of these 10 aspirates some of the cellular features of HT were misinterpreted, and the possibility of an associated neoplasm could not be ruled out. This resulted in four false positive diagnoses. In 12 (31%) FNABs from nine patients, the cytologic diagnosis of HT was not confirmed histologically. These cases included five Hürthle cell adenomas and one case each of follicular adenoma, nodular goiter, macrofollicular adenoma and malignant lymphoma. This resulted in five false negative diagnoses. CONCLUSION: These results support the value of FNAB in the diagnosis of HT. The presence of hyperplastic follicular cells on FNAB samples from HT may mimic a follicular neoplasm and result in a false positive interpretation. Adequate sampling of the thyroid is important, particularly when there is an associated lesion. The diagnosis of lymphocytic thyroiditis should not be made when only a few lymphocytes are present. Finally, pleomorphic Hürthle cells may be present in aspirates from Hürthle cell neoplasms and underdiagnosed as HT, especially when they are associated with a few lymphocytes.

Adult↗