Biomedical subjects

David Machin

Publications and source records attributed to David Machin.

42 records · Page 3Linked to original sources

PubMed2002

Tardive dyskinesia among Chinese and Malay patients with schizophrenia.

The prevalence of tardive dyskinesia (TD) was studied with the Abnormal Involuntary Movements Scale in Chinese and Malay patients with schizophrenia who were hospitalized in a Singapore state psychiatric institute. We also studied the relationship of neuroleptic-induced extrapyramidal side effects to TD. By using established criteria, the rates of TD were 40.6% for Chinese and 29.0% for Malays, higher than previously reported for Chinese subjects. Older age and lower current neuroleptic dose were significantly associated with TD. Multivariate analysis, after controlling for other salient risk variables, did not show a significant difference in TD prevalence rates between the two races. We conclude that suggested differences in interethnic rates of TD among Chinese, Malays, and Westerners are unlikely to exist and that any variation in prevalence is more likely to be determined by differences in duration of exposure and dose levels of neuroleptic drugs.

Adult↗

PubMed2002

Does being bilingual in English and Chinese influence responses to Quality-of-Life scales?

BACKGROUND: It is not known if the inclusion of bilinguals affects the results of research using Quality-of-Life (QoL) scales. OBJECTIVE: To determine the influence of bilingualism on responses to a QoL scale. RESEARCH DESIGN: In this cross sectional study, a population-based, disproportionately stratified random sample of monolingual and bilingual ethnic Chinese completed the Short-Form 36 Health Survey (SF-36) in English or Chinese (representing an alphabet and pictogram based language respectively). Cumulative logit regression models were used to assess the influence of bilingualism on SF-36 scores, while adjusting for the influence of questionnaire language and known determinants of QoL. RESULTS: English or Chinese SF-36 versions were completed by 1331 and 1380 subjects respectively (49% female, aged 21-65 years, 1366 bilingual, 501 English monolingual, 844 Chinese monolingual), with response rates exceeding 85%. Fifty percent of subjects were bilingual. Bilinguals differed from monolinguals in known determinants of QoL, being younger, better educated, and having fewer chronic medical conditions, and had SF-36 scores up to 8 points higher than monolinguals. After adjusting for these differences, bilingualism did not influence scores for any of eight SF-36 scales, whereas questionnaire language influenced scores for four scales. Use of the English SF-36 was associated with higher scores for General Health, Vitality, Role Emotional and Mental Health Scales (odds ratios 1.35-1.41), though the magnitude of these odds ratios suggests this association may not be clinically important. CONCLUSION: Bilingualism did not influence responses to a QoL scale in this large, population-based study of subjects fluent in an alphabet and/or pictogram based language.

Adult↗

PubMed1983

Acupuncture compared with placebo in post-herpetic pain.

A single blind randomised controlled study of auricular and body acupuncture compared with placebo (mock transcutaneous nerve stimulation) was performed in 62 patients with post-herpetic neuralgia. There was no difference in the amount of pain relief recorded in the two groups during or after treatment; 7 patients in the placebo group and 7 patients in the acupuncture group experienced significant improvement in their pain at the end of treatment. This suggests that acupuncture is of little value as an analgesic therapy for post-herpetic neuralgia. However the study method and the use of a mock transcutaneous nerve stimulator as a placebo may be of value when assessing the effects of acupuncture in other conditions.

Acupuncture Therapy↗

PubMed1983

On the evaluation of the clinical effects of acupuncture.

This paper reviews some of the recent randomised trials on acupuncture published in the literature, with particular reference to the definition of placebo (control), sham acupuncture and real acupuncture. Response rates of 30, 50 and 70% of placebo, sham and real acupuncture respectively, are suggested for the groups of patients studied. The statistical methodology necessary in the design of acupuncture trials, in order to detect differences of this order of magnitude, is discussed. If the postulated response rate had been envisaged at the onset of the trials here reviewed, then the majority of these trials have very low power at a conventional 5% level of significance. It is emphasised that one cannot necessarily conclude from trials which produce statistically non-significant results that acupuncture (when compared with placebo for example) is ineffective. The paper suggests that meaningful comparisons between alternative treatments may be made by using 'pain free intervals' with subsequent analysis using life table techniques. Tables are provided for determining appropriate patient numbers.

Acupuncture Therapy↗

PubMedDate not supplied

Poly-methyl pentene oxygenators have improved gas exchange capability and reduced transfusion requirements in adult extracorporeal membrane oxygenation.

The performance of poly-methyl pentene (PMP) oxygenators (Medos Hilite 7000LT) was compared with that of silicone membrane (SM) oxygenators (Medtronic 1-4500-2A) for adult extracorporeal membrane oxygenation (ECMO). Forty consecutive patients were selected retrospectively pre- and post-introduction of PMP oxygenators. They were selected according to the dates they received ECMO and were separated into two equal groups with similar backgrounds. The flow path resistance, gas and heat exchange efficiency, consumption of coagulation factors and platelets, blood transfusion requirements, and incidence of clots for each oxygenator type was assessed. Adult PMP oxygenators showed lower blood path resistance than SM oxygenators. However, lower consumption of blood products in these oxygenators was a direct result of their smaller surface area and heparin coated design, reducing contact activation of coagulation factors. These oxygenators are noticeably smaller, require lower priming volumes, and have better gas exchange capability than SM oxygenators. They showed greater stability and preservation of coagulation factors and platelets compared with SM oxygenators. They also had the advantage of a functioning integrated heat exchanger. Using a single PMP oxygenator in the first instance may be adequate for the majority of patients and would significantly reduce red blood cell consumption during ECMO.

Adult↗

PubMedDate not supplied

Development of a Smiling Touchscreen multimedia program for HRQoL assessment in subjects with varying levels of literacy.

OBJECTIVE: As low literacy affects the assessment of health-related quality of life (HRQoL) in several ways (e.g., subject eligibility and cost of administration), better approaches to HRQoL assessment in subjects with varying literacy levels are needed. METHODS: We developed a multimedia touchscreen program (the Smiling Touchscreen, ST) to administer HRQoL instruments to subjects with varying levels of Chinese language and computer literacy, using an iterative process where patients' input on design, clarity of instructions, and user-friendliness were repeatedly gathered and incorporated in development. The ST thus has several user-friendly features for low-literacy subjects (e.g., presentation of individual items using visual and auditory stimuli, voice-text synchronization, and visual analog scale with a touch and drag function), which we evaluated using qualitative and quantitative methods. RESULTS: The ST was well accepted by subjects (n = 66, 76% female, median [interquartile] age: 49.0 [40.0, 56.0]) with high (n = 43) or low (n = 23) literacy, 98% of whom found it easy or very easy to use, and 85% found the voice-text synchronization feature useful. In low-literacy subjects without computer experience (30%), none reported any difficulties using the ST. The median (interquartile) time spent to complete the ST (four Instruction and Practice screens, 24 questions, one visual analog scale) for high- and low-literacy groups was 13.9 (9.6, 23.9) and 23.2 (15.8, 26.5) minutes, respectively. Among subjects expressing a preference (n = 47), 21 (47%) favored the ST over interviewer- or self-administration. CONCLUSION: The ST is well accepted by subjects with varying literacy levels, including those without computer experience. It is thus a promising new approach for HRQoL assessment among subjects with varying literacy levels.

Acoustic Stimulation↗