An introduction to research for primary dental care clinicians part 8: stage 9. Analysing the data

INTRODUCTION: This paper, the eighth in the series, will address the ninth stage of a research project suggested in the first paper. The ten suggested stages are: 1. The initial idea (asking a research question). 2. Searching the literature. 3. Refining the research question. 4. Planning the study. 5. Writing a protocol. 6. Obtaining ethics approval and funding. 7. Piloting the project and project management. 8. Collecting data. 9. Analysing the data. 10. Writing up and disseminating the results. The previous paper outlined how to collect data during a research project. The next stage is to analyse the data that have been collected. This paper briefly introduces readers to data analysis and basic statistics. It updates the Faculty of General Dental Practice (UK) research advice sheets: Introduction to Statistics, Statistics for Research, Testing for Statistical Significance.     

Use of thiopurines in the treatment of inflammatory bowel disease is associated with an increased risk of non-melanoma skin cancer in an at-risk population: a cohort study

Background and Aim: The thiopurines azathioprine and 6‐mercaptopurine are effective in the management of patients with inflammatory bowel disease (IBD) in whom aminosalicylates, antibiotics and corticosteroids have failed to induce or maintain remission. Long‐term use of these agents has been linked to a greatly increased risk of non‐melanoma skin cancer and lymphatic cancer in organ transplant recipients. There is some evidence to suggest that IBD patients receiving thiopurines might be at increased risk of cancer. Our aim was to determine the incidence of cancer in a cohort of patients with IBD managed in our clinic, and to relate this to thiopurine exposure. Methods: We conducted a retrospective study based on the clinical and pathology records of patients attending a specialist IBD clinic at Groote Schuur Hospital, Cape Town, South Africa between 1960 and 2007. Results: We analyzed the records of 1084 patients. A total of 123 subjects (11.5%) had received thiopurine therapy. Cancer was identified in 51 patients (4.7%), including colorectal cancer (15 patients), melanoma (two patients), non‐melanoma skin cancer (seven patients) and non‐Hodgkin's lymphoma (five patients). A diagnosis of non‐melanoma skin cancer was significantly associated with thiopurine exposure (odds ratio 5.0, 95% confidence interval 1.1–22.8). Six of seven non‐melanoma skin cancers occurred in Caucasian patients, with a highly significant association with thiopurine use (odds ratio 12.4, 95% confidence interval 2.3–67.4). Conclusions: Patients with IBD who receive thiopurines are at increased risk of non‐melanoma skin cancer. The risk is highest in Caucasian patients, and is negligible in other groups.     

I don't know what I know: Evidence of preserved semantic knowledge but impaired metalinguistic knowledge in adults with probable Alzheimer's disease

Abstract

This paper will address the current practice of speech therapists setting homework for aphasic patients.     

Relationships between brain and body temperature,clinical and imaging outcomes after ischemic stroke

Pyrexia soon after stroke is associated with severe stroke and poor functional outcome. Few studies have assessed brain temperature after stroke in patients, so little is known of its associations with body temperature, stroke severity, or outcome. We measured temperatures in ischemic and normal-appearing brain using ¹H-magnetic resonance spectroscopy and its correlations with body (tympanic) temperature measured four-hourly, infarct growth by 5 days, early neurologic (National Institute of Health Stroke Scale, NIHSS) and late functional outcome (death or dependency). Among 40 patients (mean age 73 years, median NIHSS 7, imaged at median 17 hours), temperature in ischemic brain was higher than in normal-appearing brain on admission (38.6°C-core, 37.9°C-contralateral hemisphere, P=0.03) but both were equally elevated by 5 days; both were higher than tympanic temperature. Ischemic lesion temperature was not associated with NIHSS or 3-month functional outcome; in contrast, higher contralateral normal-appearing brain temperature was associated with worse NIHSS, infarct expansion and poor functional outcome, similar to associations for tympanic temperature. We conclude that brain temperature is higher than body temperature; that elevated temperature in ischemic brain reflects a local tissue response to ischemia, whereas pyrexia reflects the systemic response to stroke, occurs later, and is associated with adverse outcomes.     

Ozone and caries: a review of the literature

Ozone, either in gaseous form or as ozonated water, has been available for use as a treatment for dental caries for a decade. This paper reviews the literature on the subject by examining the findings of publications in the peer review literature. Eighteen papers were identified by a literature search. From the review of these, it was concluded that, while some laboratory studies and some short duration clinical studies have suggested that ozone may be effective in the treatment of root caries or killing of oral micro-organisms, the clinical evidence for the use of ozone in treatment of caries is not compelling.