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PubMed2006

Attitudes and opinions of NHS general dental practitioners towards clinical governance.

AIM: To assess the attitudes and opinions of NHS general dental practitioners towards clinical governance. DESIGN: This was a questionnaire based study, sent to NHS principal dentists within the West Midlands area. METHOD: A Likert scale questionnaire was developed, consisting of 26 statements in four subject areas. It was internally and externally validated, and sent to 208 practices within four geographic areas. RESULTS: A total of 150 questionnaires were returned; a response rate of 72%. For each question, no significant difference was found between areas. The cost and time involved with clinical governance emerged as the most important issues, with many respondents considering that costs of implementation might make more dentists leave the NHS. Dentists were largely positive about the principles of clinical governance and evidence based practice, but were concerned about the possibility of increasing complaints and some doubted that it would result in improved patient care. Many respondents claimed to be still confused about clinical governance and the majority considered that more guidance should be available to assist with development within dental practice. CONCLUSIONS: This survey showed that some problems exist around the introduction of clinical governance within NHS general dental practice.

Attitude of Health Personnel↗
PubMed2002

Costs and consequences of different chemotherapy regimens in metastatic colorectal cancer.

An economic sub-study was run alongside a large multi-centre randomised trial (MRC-CR06) comparing three chemotherapy regimens; de Gramont, Lokich and raltitrexed in patients with metastatic colorectal cancer. Patients in six of 45 centres in the main trial were approached to take part in the sub-study. Chemotherapy delivery costs were assessed in each sub-study centre with external validity verified by questionnaire to all other centres. Patient representativeness was assessed. Stochastic resource use data, including patient borne costs and non-hospital health service resource use were monitored prospectively. Mean total societal costs were de Gramont= 5051 pounds sterling (s.d. 1910 pounds sterling ), raltitrexed= 2616 pounds sterling (s.d. 991 pounds sterling ) and Lokich= 2576 pounds sterling (s.d. 1711 pounds sterling ). In pairwise comparisons, statistically significant mean total cost differences were shown for de Gramont vs Lokich (mean difference= 2475 pounds sterling , 95%CI 914 pounds sterling - 4037 pounds sterling , P<0.01) and for de Gramont vs raltitrexed (mean difference= 2435 pounds sterling, 95%CI 922 pounds sterling - 2948 pounds sterling , P<0.01). Sensitivity analyses showed little effect on overall costs. The main trial showed de Gramont and Lokich to be equally effective in terms of survival, quality of life and response rates but Lokich had higher toxicity and hand-foot syndrome. Raltitrexed showed similar response rates and overall survival but increased toxicity and inferior quality of life making it a clinically inferior regimen despite its ease of administration and costs. For a comparable clinical outcome, Lokich can be administered for approximately half the cost of de Gramont.

Aged↗
PubMed2003

Methyl nicotinate-induced vasodilation in generalized social phobia.

Elevated vasodilatory response (blushing) to social situations is characteristic of social phobia (SP). A relatively unexplored basis for this phenomenon is alteration in underlying vasodilatory mechanisms. To investigate this possibility, we evaluated the vasodilatory response induced by methyl nicotinate (niacin ester derivative) in 31 generalized SP patients and 41 matched healthy volunteers (HV). A patch impregnated with 0, 0.1, 0.5, 1, and 10 mM methyl nicotinate was applied to the forearm or face of subjects for 1 min, followed by 20-min laser Doppler spectroscopy blood flow monitoring. Blood flow stimulation with 1 and 10 mM methyl nicotinate was significantly reduced in SP patients by 35 and 17%, respectively. Induced blood flow was negatively correlated with patients' Leibowitz Social Phobia Scale (LSAS) at 1 and 10 mM doses. Furthermore, the maximal rate of change of vasodilatory reaction was correlated with symptom scores at 1 and 10 mM doses. Induced increases in the arm and face blood flow measurements correlated, supporting the external validity of the former location. Generalized SP patients vasodilate less to topical methyl nicotinate challenges, with effect amplification in severely ill patients. Although the mechanism for this is unclear, we propose desensitization of the prostaglandin-mediated vasodilating system as an explanation. Neuropsychopharmacology (2003) 28, 1846-1851, advance online publication, 23 July 2003; doi:10.1038/sj.npp.1300227

Adult↗
PubMed2004

Pharmacogenetics and bipolar disorder.

Bipolar disorder (BD) is a major psychiatric condition that commonly requires prophylactic and episodic treatment. There is important variability in the therapeutic response and side-effect profiles to currently available pharmacological agents. Pharmacogenetics have provided new hopes to develop more efficient treatment strategies tailored to the individual patient's needs. This review assesses nonsystematically studies using pharmacogenetic strategies in BD. Most of these studies have focused on patients selected according to lithium response, and more recently, a growing number of studies have been investigating genetic factors in mixed samples of patients classified according to response to antidepressant treatment. Although previous clinical and family studies support the use of pharmacogenetic strategies both to increase phenotype homogeneity as well as to identify genetic factors that may mediate response to treatment, most molecular studies carried out to date are still preliminary and in need of external validation. A major problem has been comparability between studies, in part, because of differences in the criteria used to define response. More attention should be paid to standardize the criteria for drug response definition.

Antidepressive Agents↗
PubMed2001

Determination of the content and identity of lidocaine solutions with UV-visible spectroscopy and multivariate calibration.

A method is proposed for the determination of the content and identity of the active compound in pharmaceutical solutions by means of ultraviolet-visible (UV-Vis) spectroscopy, orthogonal signal correction (OSC) and multivariate calibration with soft independent modelling of class analogy (SIMCA) classification and partial least squares (PLS) regression. The content was determined with PLS regression and the identity with PLS regression and SIMCA classification. The method was tested on the local anaesthetic compound lidocaine. For the validation, external test sets of both manufactured sample solutions and samples from a stability study were used. For comparison with this new method, liquid chromatography was used as a reference method. The results show that in respect of accuracy, precision and repeatability, the new method is comparable to the reference method. The main advantage over liquid chromatography is the much shorter time of analysis and the simpler analytical procedure. An estimate of the analysis time saved with the proposed method compared with using liquid chromatography, together with practical considerations, is given.

Anesthetics, Local↗
PubMed1986

Flexibility of single-subject experimental designs. Part I: Review of the basics of single-subject designs.

The discussion in this article is directed at a brief review of the basic components of single-subject experimental designs. It sets out to present some of the technical and practical advantages in developing single-subject designs to evaluate potential treatment variables and treatments. The point is made that the designs are specifically structured for applied, intervention research. In addition to explaining how the basic AB components function to allow for a controlled evaluation, a short review is included of other factors important to the scientific method such as operational definitions, reliability, repeated measures, and internal and external validity. The article serves as a foundation for the following two articles that are directed at demonstrating the flexibility of single-subject experimental studies.

Humans↗
PubMed1992

Variability of acoustic segment durations after prolonged-speech treatment for stuttering.

Existing literature suggests that one of the effects of treatment based on prolonged speech is increased durations of acoustic segments. However, the external validity of the data concerned may be questioned because the data were not based on spontaneous speech samples and were gathered from subjects with unknown treatment histories. With this in mind, the present investigation used young clients with no history of treatment based on prolonged speech and obtained pretreatment and posttreatment acoustic measures from spontaneous speech samples. Acoustic measures showed no significant posttreatment increases in durations of acoustic segments. However, for the acoustic measure of vowel duration and a measure of articulation rate, posttreatment speech samples showed significantly reduced variability. The potential theoretical and practical relevance of these findings is discussed.

Adolescent↗
PubMed1996

Idiom understanding in Australian youth: a cross-cultural comparison.

In this developmental study, idiom understanding was examined in Australian students from Grades 5 and 8 (n = 50 per group; mean ages = 10.7 and 13.8, respectively). Twenty-four idioms with familiarity ratings ranging from high to low (as judged by Australian adolescents) were each presented in a brief story context. The students read each story and selected the best interpretation of the idiom from a set of four answer choices. Results indicated that performance on the task improved as a function of increasing grade level and that idiom familiarity was significantly correlated to idiom understanding for both groups of students. These results, which were consistent with a previous study of American students of comparable educational levels (Nippold & Taylor, 1995), provide further support for the "language experience" hypothesis of figurative language development. In replicating the previous developmental study, evidence of external validity is provided.

Adolescent↗
PubMed2003

Prevalence of atopic dermatitis in Japanese adults.

BACKGROUND: Adult atopic dermatitis (AD) in Japan has become a significant social problem, with as many as one-third of adult patients with severe AD absenting themselves from work or classes due to aggravation of the disease. Reports of such patients have become increasingly common in recent years. Despite the pressing need for epidemiological studies to clarify the prevalence and distribution of AD and to determine its aetiology, no previous research has been carried out on the prevalence of AD within the adult population in Japan. OBJECTIVES: To clarify the prevalence of adult AD in Japan, using the U.K. Working Party's diagnostic criteria. METHODS: The subjects of this study were mostly government officials or their family members visiting the Medical Center of Health Science, Toranomon Hospital in Tokyo for annual health check-ups in the period from September 1997 to August 1998. Questionnaires completed by 10 762 persons (8076 men and 2686 women) aged 30 years or above were analysed. The questionnaire consisted of 14 questions on allergic disease. The U.K. Working Party's diagnostic criteria were used after translation into Japanese. Three types of prevalence were used as indicators of prevalence: point, 1-year and lifetime prevalence. RESULTS: The point prevalence, 1-year prevalence and lifetime prevalence of AD in Japanese adults were 2.9%, 3.0% and 3.3%, respectively. No significant statistical differences were observed between the sexes or among age groups within each sex. The survey indicated that 88.6% of those who had ever had AD were currently affected by active AD, while 93.4% of those who had had at least one episode of AD in the past had experienced an episode over the previous year. CONCLUSIONS: This study gives the first indication of the prevalence of adult AD among the Japanese, based on the U.K. criteria. Both the internal and external validity of this study are believed to be high; it would be safe to conclude that the 1-year prevalence of AD in Japanese adult populations living in urban areas is 3.0%.

Adult↗
PubMed2000

A retrospective case-controlled study of 1490 consecutive patients presenting to a neuro-otology clinic to examine the relationship between blood lipid levels and sensorineural hearing loss.

This study set out to test the null hypothesis that the distribution of blood lipid levels is the same in a population with a sensorineural hearing loss (SNHL) as in a control population. Hyperlipidaemia has been implicated as an aetiological factor in SNHL; however, the majority of reports are retrospective, lack adequate controls, or are based on a series of cases which may represent incidental findings and not a true causal relationship. In all, 1490 consecutive patients who presented to a neuro-otology clinic were studied retrospectively. This group is exceptional in that all patients had had fasting lipid profiles done regardless of their presenting problem. Those with a mean SNHL > 25 dB (0.5, 1, 2 and 4 kHz) were compared with those with hearing thresholds < or = 25 dB. An analysis of variance was also done. The study group was also compared with the National Study of Hearing data set to add external validity. Simple correlations were found between hearing thresholds and many parameters such as blood pressure, fasting glucose, triglyceride or fasting cholesterol. Analysis of variance of the neuro-otology group, controlling for variables such as age and sex, showed no significant association between hearing and blood pressure, packed cell volume, mean corpuscular volume, fasting glucose, triglyceride or fasting cholesterol. However, when general linear interactive modelling was used to analyse hearing thresholds, raised total fasting cholesterol was associated with significantly better hearing threshold levels. This study leads to a rejection of the Null hypothesis that the distribution of lipid levels is the same in a population with a hearing loss as in a control population, as hearing thresholds were found to be significantly better in those with raised cholesterol levels.

Adolescent↗
PubMed2001

A prospective case-control study of 50 consecutive patients presenting with hyperlipidaemia.

The literature contains many references which refer to a causal relationship between hyperlipidaemia and hearing loss, but the majority of reports lack adequate controls, or are based on a series of cases which may represent incidental findings. This prospective case-control study compared a restricted population of 50 consecutive hyperlipidaemic patients attending a lipid clinic whose fasting lipid levels were > 2 SDs above the population mean with a control population recruited from patients undergoing nasal surgery for structural abnormalities (n = 159). The National Study of Hearing data was also compared with both groups in order to provide external validity to the control group. This study showed no consistent differences in the hearing thresholds of the hyperlipidaemic group compared with either control group. The Null hypothesis that sensorineural hearing loss is no greater in a population whose fasting blood lipids are raised > 2 SDs above the population mean level than in a control population cannot be refuted given the variability of the data.

Adult↗
PubMed2000

A case for case studies: exploring the use of case study design in community nursing research.

The case study has become an accepted vehicle for conducting research in a variety of disciplines. However, the meaning behind the term is not always made explicit by researchers and this has given rise to a number of assumptions which are open to challenge, and to questions about the robustness of the method. This paper explores some of the issues arising from one particular definition of case study research, used in a study by Yin which examined the practice of case management in community nursing. Four main areas are discussed. First, defining 'case' is seen to pose questions about the relationship of the phenomenon to its context, the degree of researcher control over case definition, the limits to what may constitute a 'case' and what is meant by the term 'unit of analysis'. Second, the relevance of external validity to case study research is supported through the use of a number of tactics, in particular Yin's concept of replication logic, which involves generalizing to theory, rather than to empirical data. Third, the use of method triangulation (multiple methods of data collection) is advanced as a means of enhancing construct validity in research where data converge around a particular theory. Finally, the relationship of the case study to theory construction, through the prior development of 'propositions' is discussed. Each of these issues is applied to the design and conduct of a research study based closely on Yin's multiple case study framework. Thirteen 'cases' were selected of case management practice and data were collected through interviews and examination of literature and documentation, to explore the suitability of community nurses for the role. It is concluded that, given the appropriate subject matter, context and research aims, the case study method may be seen as a credible option in nursing research.

Case Management↗
PubMed2001

The Data Protection Act (1998): implications for health researchers.

AIMS: This paper reports on the methods used in two studies to obtain access to subjects to comply with the common law duty of confidence laid out in the Data Protection Act (1998) and discusses the researchers' problems in interpreting the procedures. RATIONALE: The amendments to the United Kingdom (UK) Data Protection Act (1998) are causing confusion within the health service and academic institutions. There is a need to balance patient confidentiality with the requirement to conduct vital, unbiased research in which health service professionals are not subject to ethical dilemmas. This paper examines the recruitment methods used in two studies in which the researchers' attempts to adhere to the requirements lengthened the study costs and may have produced less reliable results. METHODS: The methodological difficulties in two studies are presented. In Study 1, the difficulties encountered when the Multicentre Research Ethics Committee refused permission for researchers to recruit patients directly to a multicentre randomized controlled trial are discussed. In Study 2, the method used to compile a sampling frame for a national questionnaire survey following the eight principles of the Act are described. FINDINGS: Our experience has shown that health care professionals are increasingly required to recruit patients to intervention trials, and that researchers are not allowed access to the names of patients or other subjects to ask them for consent to participate in a study. The requirement for researchers to use "intermediaries" to obtain consent from and recruit subjects to studies increases the risk of selection bias, may expose the practitioner to ethical difficulties and may compromise the external validity of trial results. There is also a danger that research costs will soar when the Data Protection Act (1998) is fully realized. CONCLUSION: The Data Protection Act (1998) is currently being interpreted in a number of different ways. We conclude there is an urgent need for consensus within the health service and academic communities.

Clinical Trials as Topic↗
PubMed2004

Coping strategies of people with kidney transplants.

BACKGROUND: There has been little research into coping process following renal transplantation, but it has been shown that health-related stress is not eliminated and that fear of rejection and economic factors are the most stressful issues. Coping strategies used have included prayer, looking at problems objectively, and trying to main control over the situation. AIM: The study was concerned with kidney transplant patients and their efforts to cope with problems posed by the transplantation and treatment. The aim was to describe and compare the use and perceived effectiveness of different coping strategies in people after kidney transplant with an age, gender and civil status-matched sample of the general Swedish population. METHODS: Coping was assessed by the Jalowiec Coping Scale and self-rated efficiency with visual analogue scales. From a total of 73 post-transplant patients, a consecutive series of 30 was compared with an age, gender and civil status-individually matched sample of the general Swedish population (n = 30). Data were collected from 1994 to 1997. RESULTS: The patient sample used significantly more optimistic, self-reliant, supportive and emotive coping than the general population sample. Evasive, emotive, and fatalistic coping were associated with low perceived efficiency in handling various aspects of the condition. STUDY LIMITATIONS: The study design does not permit causal conclusions and the patient sample was relatively small and non-randomly chosen, which could affect its external validity. CONCLUSIONS: The results suggest that assessment of coping strategies should be explored in clinical nursing practice so that nurses can encourage the use of those likely to be more useful, and discourage those with possible negative effects.

Adaptation, Psychological↗
PubMed2004

Enhancing Delphi research: methods and results.

BACKGROUND: The Delphi method provides an opportunity for experts (panelists) to communicate their opinions and knowledge anonymously about a complex problem, to see how their evaluation of the issue aligns with others, and to change their opinions, if desired, after reconsideration of the findings of the group's work. Delphi studies have the potential to provide valuable information, yet few researchers have taken further steps to support or refine their findings. Without this step there is a potential threat to the applicability, or external validity, of the results. AIMS: The purpose of this article is to present an argument for further inquiry to enhance and support Delphi findings, and specific approaches to this will be considered. METHODS: Methods to enhance, expand, or refine Delphi study findings are described. Mixed method design within a Delphi study on midwifery practice is described, and a follow-up narrative study to examine the findings is presented. FINDINGS: Selected results from the follow up narrative study are presented to convey how the narrative data clarified the Delphi findings. Together, the studies provide a more robust depiction of midwifery practice, process, and outcomes. Although there were similarities to the dimensions identified previously, there was a more dynamic focus and explanation of the interaction between the midwife, the woman who had received midwifery care, and the health care system. STUDY LIMITATIONS: Lack of diversity in the sample and the midwives' familiarity with the author's past research represent a potential threat to the findings. Prolonged interviews and multiple narratives were gathered in an effort to control for this. CONCLUSION: Delphi studies are research exercises conducted by a panel of experts. Designing studies to further enhance, clarify, or refine their findings from the context of practice holds promise for their ability to influence clinical care.

Data Collection↗
PubMed2003

Working with sex offenders with intellectual disability: evaluation of an introductory workshop for direct care staff.

BACKGROUND: Sexual aggression by men with intellectual disability (ID) is a serious problem requiring attention from the relevant agencies. Training for staff working with this problem is often not given sufficient attention and is rarely evaluated. In the present study, an introductory workshop for direct care staff that aimed to increase knowledge and improve attitudes towards work with this client group was evaluated. METHOD: Sixty-six staff working in inpatient and community settings completed a 2.5-day workshop. Before training began, the participants completed a survey questionnaire concerning their experiences of work with this client group. An assessment of their knowledge and attitudes was carried out prior to and at the end of training in order to evaluate any changes. The participants also rated the effectiveness of the workshop and their level of satisfaction with the training at the end of the workshop. RESULTS: The participants' knowledge and attitudes improved significantly following the workshop. Staff with greater experience over time and those who had worked with fewer sex offender clients responded to different aspects of the training. The participants' ratings indicated that they were highly satisfied with the training and found it to be effective. CONCLUSIONS: Brief workshop training is acceptable to and can be effective in improving the knowledge, attitudes and confidence of direct care staff working with sex offenders with ID. However, because the results are based on participant self-report, caution should be exercised concerning their external validity.

Attitude of Health Personnel↗
PubMed1997

The value of simulations in the management education of nurses: students' perceptions.

This paper examines the use of simulations in the education of student nurses as part of their preparation for management responsibility. A review of the literature indicates that there is little published work on this topic and that those evaluations that have been reported invariably occur at the end of the exercise, thus giving an incomplete picture of the simulation. The nature and format of the simulation, used with 128 students undertaking a pre-registration/diploma in higher education course, is described. Results from student evaluations immediately following the exercise and after 13 weeks of clinical experience are presented. The findings indicate that this is a realistic and enjoyable way of learning which adequately prepares students for management experience in subsequent clinical allocations. Issues concerned with internal and external validity of simulations and areas for further research are explored.

Attitude of Health Personnel↗
PubMed2002

Heterogeneity of temporomandibular disorders: cluster and case-control analyses.

Cluster analysis has been applied to the classification of temporomandibular disorders (TMD). The factors most often used in these classification systems are psychological and psychosocial. The aim of this study is to classify individuals diagnosed with TMD, by using cluster analysis based on their clinical condition and the global severity of the disease. In this study, one investigator selected the patients at the dental clinics located at the Jewish General and Montreal General hospitals, Montreal, Canada, from September 1994 to December 1997. The study population included 162 outpatients. The results of this study indicated the existence of four TMD subgroups: three TMD pain groups with localized or generalized disorder related to different levels of interferences in their life and a non-pain, but disabled group. External validation of the cluster solution support the replication of the four groups and allow for further interpretation of the patients' profiles. Clenching-grinding and depression were related to the groups presenting generalized TMD. Orthodontic treatment and female sex, however, were the factors associated with a more localized condition. This classification system may provide a better understanding of the TMD subgroups and clues for the treatment and prognosis of TMD patients.

Adolescent↗