Biomedical subjects

R Lay-Yee

Publications and source records attributed to R Lay-Yee.

16 recordsLinked to original sources

PubMed2003

Preventable in-hospital medical injury under the "no fault" system in New Zealand.

OBJECTIVES: To describe the pattern of preventable in-hospital medical injury under the "no fault" system and to assess the level of serious preventable patient harm. DESIGN: Cross sectional survey using a two stage retrospective assessment of medical records conducted by structured implicit review. SETTING: General hospitals with over 100 beds providing acute care in New Zealand. PARTICIPANTS: A sample of 6579 patients admitted in 1998 to 13 hospitals selected by stratified systematic list sample. MAIN OUTCOME MEASURES: Occurrence, preventability, and impact of adverse events. RESULTS: Over 5% of admissions were associated with a preventable in-hospital event, of which nearly half had an element of systems failure. The elderly, ethnic minority groups, and particular clinical areas were at higher risk. The chances of a patient experiencing a serious preventable adverse event subsequent to hospital admission were just under 1%, a figure close to published results from comparable studies under tort. On average, these events required an additional 4 weeks in hospital. System related issues of protocol use and development, communication, and organisation, as well as requirements for consultation and education, were pre-eminent. CONCLUSIONS: The risk of serious preventable in-hospital medical injury for patients in New Zealand, a well established "no fault" jurisdiction, is within the range reported in comparable investigations under tort.

Adolescent↗

PubMed2001

Adverse events regional feasibility study: methodological results.

AIMS: To assess the feasibility of research into the occurrence, causation and prevention of adverse events (AEs) in New Zealand public hospitals. METHODS: A two-stage retrospective review was carried out on 1,575 medical records selected by systematic list sample from admissions for 1995 in three public hospitals in the Auckland region. Following initial screening, medical records were subject to structured implicit review using a standardised protocol. Feasibility measures, using international benchmarks where possible, were: adequacy of sample selection; completeness of medical records; reliability and validity of screener and reviewer judgements; internal consistency and face validity of AE determination and preventability assessment. RESULTS: The sample selection procedure was effective, although nearly 10% of records could not be secured. Information in medical records was sufficient for the identification and analysis of AEs. Adequate levels of agreement were achieved for screener and reviewer judgements, with kappa scores ranging between 0.302 and 0.622 and positive predictive values between 50.0% and 89.7%. The criteria for AE determination showed internal consistency and face validity, as did those for preventability. CONCLUSIONS: Research into the occurrence, causation and prevention of AEs in New Zealand health care settings is methodologically feasible and meets international benchmark standards.

Algorithms↗

PubMed2001

Adverse events regional feasibility study: indicative findings.

AIMS: To identify substantive findings of potential clinical and managerial significance from a regional feasibility study of adverse events (AEs). METHODS: A standardised protocol using structured implicit review was applied to 142 AEs generated in an audit study of three public hospitals in the Auckland region for admissions in 1995. Areas of potential significance addressed were: timing, location and impact of AEs; preventability; and clinical context and predictability. RESULTS: 142 cases were identified as AEs (10.7% of 1,326 screened records). In 102 cases, 7.7% of all screened records, it was considered to be more likely than not that health care management contributed to the AE. About half the reported AEs occurred before the index admission, the majority outside hospital. Over half of all events resulted in disability that was resolved within a month. An average 6.7 extra days stay in hospital were attributable to AEs. For 60% of AEs the evidence for preventability was either low or nonexistent. Areas of potential prevention were predominantly educational. Over half of all AEs occurred in a surgical context. Medical AEs were more likely to have occurred outside hospital, to be drug-related, to be associated with an acute admission, to be classified as highly preventable, and to have a greater impact on hospital stay. CONCLUSIONS: Although the data generated by a feasibility study must be treated with caution, the pattern of results is consistent with comparable Australian findings and is of potential clinical and managerial significance.

Drug-Related Side Effects and Adverse Reactions↗

PubMed2001

Nappy handling and risk of giardiasis.

We did a case-control study to identify modifiable risk factors for giardiasis in people aged 15-64 years living in Auckland, New Zealand. 183 patients with stool-positive Giardia spp referred to community laboratories were compared with 336 age-matched controls identified randomly from the Auckland telephone book. Exposure information for the previous 3 weeks was obtained retrospectively by telephone. Nappy changing was associated with a four-fold increased risk of infection after controlling for other confounders. We conclude that children wearing nappies could be an important source of giardia infection in the community.

Adolescent↗

PubMed2000

The "supply hypothesis" and medical practice variation in primary care: testing economic and clinical models of inter-practitioner variation.

Medical practice variation (MPV) is marked, apparently ubiquitous across the health sector, well documented, and continues to be a focus of professional and policy interest. MPV have stimulated two paths of investigation, one economic in emphasis and the other more-clinical in orientation; while health economists have stressed the potential role of income incentives in medical decision-making, health services research has tended to emphasise clinical ambiguity as a factor in practitioner decisions. Both sets of explanations converge in an implicit "supply hypothesis" that posits contextual practitioner and practice attributes as influential in clinical decisions. Data on inter-practitioner variation are taken from a large and representative regional survey of general practitioners in New Zealand, a country in which unsubsidised fee-for-service is the predominant mode of remuneration in primary care. The paper assesses the impact on three important areas of clinical decision-making prescribing, test ordering, request for follow-up -- of three key conceptual dimensions -- income incentives, physician agency, and clinical ambiguity (operationalised as local doctor density, practitioner encounter initiation, and diagnostic uncertainty respectively). Predictions are made about inter-practitioner variations in the rate of clinical activity in the three areas. The results of the analysis using multi-level statistical techniques are: 1. the extent of competition -- local doctor density -- seems to have no effect on the pattern of clinical decision-making; 2. doctor-initiated visits are, if anything, associated with lower rates of intervention; 3. diagnostic uncertainty is associated with higher rates of investigations and follow-up, both of which have clinical plausibility; 4. there is no significant interaction effect between density and uncertainty. It is concluded that, for the clinical activities studied and for the practitioner attributes as operationalised in this investigation, a clinical, rather than an economic, model of practitioner decision-making provides a more plausible interpretation of inter-practitioner variation in rates of clinical activity in general practice. The "supply hypothesis" requires further analytical refinement and empirical assessment before it can be applied as a generic explanatory framework for MPV.

Family Practice↗

PubMed2000

Do physician practice styles persist over time? Continuities in patterns of clinical decision-making among general practitioners.

OBJECTIVES: This study seeks to determine whether there are identifiable differences in patterns of clinical decision-making among family physicians, and whether these patterns persist over time. METHODS: A representative cross-sectional survey of general practice encounters in the Waikato region of New Zealand in 1979-1980 was repeated in 1991-1992. Patterns of clinical decision-making were operationalised as practitioner rates for writing a prescription, ordering a laboratory test or radiological examination and the recommendation of a future follow-up office visit at a specified date. Comparable data were available for a cohort of 50 physicians in both surveys. Multi-level techniques and a simulation exercise were used to study the patterns of decision-making over time. RESULTS: Raw, unadjusted correlations for the 50 family physicians between the two surveys were 0.24, 0.14 and 0.55 for rates of prescribing, investigations and follow-up, respectively. However, these correlations increased substantially, to 0.55, 0.41 and 0.70, once account was taken of case mix, data clustering and inter-practitioner variation in patient sample size. The extent of this recovery of the underlying correlations was confirmed in a parallel simulation exercise. CONCLUSIONS: This study confirms the existence of substantial and durable individual practice styles in primary medical care, with implications for the development and successful implementation of clinical guidelines.

Cross-Sectional Studies↗

PubMed1999

Practice nurses in the Waikato, 1991-1992, I: Occupational profile.

AIMS: To describe the personal characteristics, working conditions, clinical activities and professional development of a representative sample of practice nurses in the Waikato during the period 1991-1992. METHODS: The data are from a survey of practice nurses drawn from a larger study of general practice carried out in the Waikato (the WaiMedCa Study). Eighty-nine percent of the 107 practices in the region participated in the study. The practice nurse survey was carried out on the 189 nurses working in these practices. Of these 149 replied, representing a response rate of 79%. RESULTS: On average, there was one nurse for each solo practice and two in most other practices. Only two practices--both solo--did not employ a nurse. Practice nurses were female and aged between 30 and 50. While only one-third had received a postgraduate qualification, two-thirds had been to recent professional development courses. The majority had worked as a practice nurse for between one and ten years. Nurses averaged just under 15 telephone contacts a day and 28 face-to-face contacts a week. Nurses' workload comprised general measurements and assessments, monitoring and surveillance procedures (such as diabetes, asthma and child development), and counselling and women's health activities. CONCLUSION: Practice nurses are an accepted and essential part of primary health care in New Zealand. However, their potential is probably underdeveloped and they could be more fully utilised for a wider range of nursing functions.

Adult↗

PubMed1998

Trends in general practice in the Waikato, 1979-80/1991-92, II: Social variations in service use and clinical activity.

AIMS: To document trends in ethnic group and occupational class differences in the use of general practitioner services and in patterns of clinical activity for the Hamilton Health District of the Waikato over the period 1979-80 to 1991-92. METHODS: The data are drawn from a baseline and a follow-up survey of general practice in the Waikato region representing a one per cent sample of all in-surgery, in-hours, week-day encounters at two points in time. The data were recorded by participating general practitioners in four collection weeks spaced over the period of a year. In total, 9468 and 10,235 patient encounter forms were completed respectively. RESULTS: Over a period in which service availability and rates of medical contact grew, there was a relatively greater increase in utilisation among Maori and lower socioeconomic groups: between the two surveys the ratio of Maori to non-Maori rates increased from 0.8 to 1.0 and the ratio of visits for lower to higher socioeconomic groups grew from a differential of 2.5 to one of 3.1. More serious conditions apart, these changes seemed to occur uniformly regardless of the severity, amenability or susceptibility of the condition presented to the general practitioner. Changes in ethnic group and occupational class patterns of service activity almost exactly mirrored these trends. CONCLUSIONS: A notable relative increase in rates of contact for primary medical care among Maori and lower socioeconomic groups seems to have accompanied the growth in the 1980s of the availability of general practitioner services in this region of New Zealand.

Data Collection↗

PubMed1998

Trends in general practice in the Waikato, 1979-80/1991-92, I: Practitioner availability, service use and clinical activity.

AIMS: To document trends in availability and use of general practitioner services and in patterns of clinical activity for the Waikato over the period 1979-80 to 1991-92. METHODS: The data are drawn from a baseline and a follow-up survey of general practice in the Waikato region representing a 1% sample of all in-surgery, in-hours, week-day encounters at two points in time. The data were recorded by participating general practitioners in four collection weeks spaced over the period of a year. In total, 9468 and 10,235 patient encounter forms were completed. RESULTS: While the number of general practitioners increased by a half over the period, average workload declined by a fifth, the inflation-adjusted value of the usual adult fee increased by nearly 50% and visits went up by an average of a half a visit a year. Clinical activity declined for prescribing but increased for referral and follow-up. CONCLUSIONS: The increase in availability of general practitioners over the last decade has been associated with significant changes in patterns of practice organisation, service utilisation and clinical activity. Further research is required into the potential impact of greater service availability on patient demand and resource use.

Adult↗

PubMed1998

Cardiovascular disease risk factors in 65-84 year old men and women: results from the Auckland University Heart and Health Study 1993-4.

AIM: To describe the distribution of the major cardiovascular risk factors among older men and women in the Auckland region, New Zealand. METHODS: Means and prevalences of the major cardiovascular risk factors were estimated for non-Maori, non-Pacific Islands men and women in the age groups 65-74 and 75-84 years using data from the 1993-4 survey of the University of Auckland Heart and Health Study, a cross-sectional, population-based study of cardiovascular risk factors. RESULTS: 996 people aged 65-84 years participated, with men and women and the two ten-year age groups almost equally represented. Fewer than half engaged in regular leisure time physical activity; around 35% were overweight (BMI 25-30) and 10% were obese (BMI > 30). Total mean cholesterol levels were higher in women and 46% of women had a cholesterol level > or = 6.5 mmol/L compared with only 17% of men. However, total cholesterol:HDL ratios were higher among men. Age and sex differences in blood pressure were small. Around 50% had raised blood pressure (BP > 150/90) or were currently on antihypertensive medication; only 8% smoked; around 6% were diabetic. Almost 8% had three or all of four major modifiable cardiovascular risk factors (elevated blood pressure, total cholesterol:HDL ratio > or = 6.5, current smoking and physical inactivity). CONCLUSIONS: These results are broadly comparable to those from other Western populations. Differences between 65-74 and 75-84 year age groups are few but important differences in cholesterol, smoking and physical activity between older men and women are noted. These findings indicate that there is considerable potential for prevention of cardiovascular disease among older people.

Aged↗

PubMed1998

Variations in hospitalization rates for asthma among black and minority ethnic communities.

In response to the introduction of ethnic monitoring within the U.K. hospital inpatient data set, this study investigates the variations in secondary healthcare utilization by Black and minority ethnic communities whose cause of admission is related to asthma. The study examines all residents of the West Midlands: over 5 million people, of whom 8.5% are from Black and minority ethnic groups. A retrospective study of 15,921 asthma-related hospital admissions, from 1 April 1995 to 31 March 1996, was carried out. Age-standardized admission rates were higher in all Black and minority ethnic groups studied than in the White group. There were elevated rates in Black children aged 5-14 years, and particular differences were observed for Indian and Bangladeshi men and women aged 65 years or over. Emergency admissions to hospital for asthma were strongly associated with patients' socioeconomic background but this was largely observed for Black and minority ethnic groups that also generally experience high levels of deprivation. The findings support previous studies which suggest that hospital utilization rates for asthma among people from Black and minority ethnic groups are high compared with the White group, despite little evidence in measured prevalence. This study suggests that ethnic background is more important in asthma admissions than deprivation, which raises serious concerns on the appropriateness and quality of asthma care for these patient groups within our society. Future studies need to examine pathways to care, that is the health-seeking behaviour of Black and minority ethnic groups, the type of treatment received at the primary care level and referral patterns to secondary care.

Adolescent↗

PubMed1998

Coronary events and exposure to environmental tobacco smoke: a case-control study from Australia and New Zealand.

OBJECTIVES: To estimate the relative risk of coronary heart disease (CHD) associated with exposure to environmental tobacco smoke (ETS). DESIGN: Population-based case-control study. SUBJECTS: Cases were 953 people identified in a population register of coronary events, and controls were 3189 participants in independent community-based risk factor prevalence surveys from the same study populations. SETTING: Newcastle, Australia and Auckland, New Zealand. MAIN OUTCOME MEASURES: Acute myocardial infarction or coronary death. RESULTS: After adjusting for the effects of age, education, history of heart disease, and body mass index, women had a statistically significant increased risk of a coronary event associated with exposure to ETS (relative risk (RR) = 1.99; 95% confidence interval (CI) = 1.40-2.81). There was little statistical evidence of increased risk found in men (RR = 1.02, 95% CI = 0.81-1.28). CONCLUSION: Our study found evidence for the adverse effects of exposure to ETS on risk of coronary heart disease among women, especially at home. For men the issue is unclear according to the data from our study. Additional studies with detailed information on possible confounders and adequate statistical power are needed. Most importantly, they should use methods for measuring exposure to ETS that are sufficiently accurate to permit the investigation of dose-response relationships.

Adult↗

PubMed1997

Maori/non-Maori patterns of contact, expressed morbidity and resource use in general practice: data from the Waikato Medical Care Survey 1991-2.

AIMS: To compare patterns of contact, expressed morbidity and resource use in primary care for a representative sample of patients of Maori and non-Maori background. METHODS: The data are drawn from a survey of general practice in the Waikato region representing a one per cent sample of all week day encounters. The data were recorded by participating general practitioners in four collection weeks spaced over the period of a year. In total, 12,833 patient encounter forms were completed. RESULTS: Annual rates of general practitioner contact for Maori are slightly lower than those for patients of non-Maori background. The case-mix pattern of general practitioner contact is very similar between the two groups. There is a limited correspondence between ethnic patterns of general practitioner usage and health need (as measured by mortality levels and rates of public hospital discharge). CONCLUSIONS: The near equivalence in ethnic rates of general practitioner contact revealed in this study contrasts strikingly both with the level of hospitalisation for Maori, which is nearly double that of non-Maori, and with the difference in mortality rates (30% higher for Maori). Attention devoted to improving access to general practitioner services among Maori may be necessary if important areas of ill health and hospital resource use are to be addressed effectively.

Adolescent↗

PubMed1997

Patterns of general practitioner usage among Pacific people: indicative results from the Waikato Medical Care Survey 1991-2.

AIMS: To report patterns of medical contact in a representative sample of Pacific people attending the general practitioner. METHODS: The data were drawn from a survey of general practice in the Waikato region representing a one per cent sample of all weekday encounters. In total, 12,833 patient encounter forms were completed. Just over one per cent of all encounters were recorded for patients of Pacific Islands background. RESULTS: Rates of medical contact for Pacific patients were lower-3.4 visits per year versus 4.5 for the whole sample-fewer follow up visits were requested (71% versus 76.2%), presentation was delayed (4.9 days from onset versus 3.7 for the sample) and there was an apparently lower level of rapport achieved. CONCLUSION: Overall levels of medical contact and return visits among Pacific patients appear to be lower and presentation delayed in this Waikato sample.

Adolescent↗

PubMed1996

New Zealand guidelines for the management of dyslipidaemia: implications for treatment in an urban New Zealand population.

AIMS: The paper uses coronary heart disease risk factor prevalence data from a defined urban population to assess the potential impact of implementing the New Zealand National Heart Foundation "Guidelines for detection and management of dyslipidaemia" on the treatment of dyslipidaemia in New Zealand. METHODS: Coronary heart disease risk factor data was collected on an age stratified random sample of Auckland residents aged 35-74 years. The 10 year absolute risk of coronary heart disease was calculated for each participant aged between 35-64 years and management options determined from the National Heart Foundation guidelines. The Framingham equation used in these guidelines was used to extrapolate the 10 year risk of a coronary event in the 65-74 year age group. The proportions of participants potentially requiring treatment with lipid modifying medication were identified and extrapolated to the New Zealand European population. A sensitivity analysis was undertaken to assess the impact of 5% and 10% reductions in total cholesterol following dietary intervention on numbers meeting the drug treatment criteria. RESULTS: The proportion of participants potentially requiring lipid modifying treatment based on the guidelines was considerably higher than estimates of current treatment rates in each age group. The number meeting the treatment criteria increased dramatically with age. By the age of 65-74 years one in five participants met the drug treatment criteria. A 5% and 10% reduction in total cholesterol following dietary intervention reduced the proportion of participants potentially requiring drugs by almost one quarter and one half respectively. CONCLUSION: The approach taken by the New Zealand National Heart Foundation guidelines appropriately gives highest priority to patients at highest risk of a coronary event. If this high risk approach is extrapolated to older age groups, it will lead to more drug treatment among the elderly. Further evidence from randomised controlled trials on benefits of using cholesterol modifying medication in older age groups is required. Future guidelines need to address specifically criteria for use of lipid modifying medications in older age groups. Reductions in the numbers meeting drug treatment criteria following 5% and 10% reductions in total cholesterol reinforces the importance of dietary management.

Adult↗

PubMed1991

The diet of Auckland men and women aged 25-64 years.

The dietary intake of a sample of 537 men and 372 women aged 25-64 years, randomly selected from the Auckland general electoral rolls, was assessed in order to describe current nutritional patterns in Auckland and to compare dietary intakes between men and women. A 118 item food frequency questionnaire was given to each participant to recall usual intake over the previous three months. After adjusting for energy intake, men consumed significantly more fat and cholesterol than women, consistent with their increased intake of red meat (median serves per month = 28 for men, 23 for women) and their greater tendency to eat fried meat (80.3% v 71.7%) and to drink full cream milk (82.7% v 70.7%). In contrast, women consumed more carbohydrate and fibre than men after adjusting for energy, consistent with their increased intake of vegetables (median serves per month = 136 for women, 116 for men) and fruit (median serves per month = 71 for women, 39 for men). These dietary differences between men and women may partly explain the increased coronary heart disease rates in men.

Adult↗