Growth and motion of liquid alloy droplets of Au on Ge(110).

The growth of low-dimensional nanostructures of Au on Ge(110) and their temperature-induced motion were observed with Low Energy Electron Microscopy (LEEM). Ge(110) was dosed with 0.5-4 ML of Au and heated to 850°C. Above 500°C, liquid AuGe eutectic alloy islands grew on the surface. Islands were 0.3-3.0µm in width, 1-10µm in length, and elongated in the [11¯0] direction. Above 600°C, islands began moving with speeds of 0.1-1.0µm/s, absorbing smaller stationary islands upon collision and increasing in size to more than 100µm in width. A temperature gradient of ∼0.017°C/µm across the sample results in a gradient in the Ge concentration across the islands, inducing their movement in the direction of increasing temperature. Optical microscopy confirmed that the large islands moved from the cooler edges of the sample towards its hotter center. The mechanism for motion of the droplets is discussed, and the island velocities fit well to a model for diffusion-driven motion of the liquid droplet. When the temperature was subsequently lowered, islands became supersaturated with Ge, which crystallized on the island edges.

Systematic review of the quality of surgical mortality monitoring.

BACKGROUND: Mortality is the most tightly defined and used adverse event for audit and performance monitoring in surgery. However, to identify cause and therefore scope for improvement, accurate and timely data are required. The aim of this study was to perform a systematic review of the quality of measurement, reporting and monitoring of mortality as an outcome after surgery. METHODS: A systematic review of published literature was undertaken for the 7-year interval 1993-1999. Grey and unpublished literature was obtained through the Royal College of Surgeons of England, from UK national audits and routine national hospital data collections. RESULTS: Eligible monitoring systems included six UK national surgical audits, and cardiac and vascular surgery monitoring systems from North America and the UK. The definitions of 'surgical death' varied in several respects and deaths after discharge from hospital were rarely ascertained unless there was routine linkage to national death registers. There were very few published studies on validation of the completeness and accuracy of the data collection. CONCLUSION: A comprehensive data collection system is needed for improving clinical performance, with ownership, but not necessarily data collection, resting with the surgeons concerned. Recording of risk factors and deaths after discharge from hospital is essential, whatever data collection system is used.

Is there ageism in oncology?

OBJECTIVE: To use routine data to explore age-related decision making in the hospital management of colorectal cancer. DESIGN: Retrospective analysis of linked Scottish cancer registry and hospital discharge data for colorectal cancer. SETTING: All Scottish general hospitals. PARTICIPANTS: All patients on the Scottish colorectal cancer registry 1992-6 (n = 15,299). MAIN RESULTS: Histological verification was used to indicate the "gold standard" of investigation. Definitive surgery and chemotherapy were used as indicators of treatment received. After adjusting for demographic factors, tumour sub-site, co-morbidity and route of first admission, increasing age was associated with markedly decreased rates of histological verification, surgery and chemotherapy. It is still not possible to be sure whether there is ageism in the management of older patients with colorectal cancer. However, the rate of histological verification fell markedly with increasing age, making it questionable whether decisions to treat were based on best clinical practice at the time. Differences observed between this study and clinical trial data may represent the margin of ageism between everyday clinical practice and controlled conditions. CONCLUSIONS: The value of this analysis lies in the fact that the data come from routine clinical practice rather than special studies. The improved content of Scottish cancer register and the ability to link it to hospital care provides a useful baseline for monitoring adherence to clinical guidelines.

Problems in using health survey questionnaires in older patients with physical disabilities. The reliability and validity of the SF-36 and the effect of cognitive impairment.

Reliability and validity of the SF-36 Health Survey Questionnaire was assessed in older rehabilitation patients, comparing cognitively impaired with cognitively normal subjects. The SF-36 was administered by face-to-face interview to 314 patients (58-93 years) in the day hospital and rehabilitation wards of a department of medicine for the elderly. Reliability was measured using Cronbach's alpha (for internal consistency) on the main sample and intraclass correlation coefficients on a test-retest sample; correlations with functional independence measure (FIM) were examined to assess validity. In 203 cognitively normal patients (Mini-Mental State Examination > or =24), Cronbach's alpha scores on the eight dimensions of the SF-36 ranged from 0.545 (social function) to 0.933 (bodily pain). The range for the 111 cognitively impaired patients was 0.413-0.861. Cronbach's alpha values were significantly higher (i.e. reliability was better) in the cognitively normal group for bodily pain (P = 0.003), mental health (P = 0.03) and role emotional (P = 0.04). In test-retest studies on a further 67 patients, an intraclass correlation coefficient of 0.7 was attained for five out of eight dimensions in cognitively normal patients, and four out of eight dimensions in the cognitively impaired. Only the physical function dimension in the cognitively normal group attained the criterion level (r > 0.4) for construct validity when correlated with the FIM. In this group of older physically disabled patients, levels of reliability and validity previously reported for the SF-36 in younger subjects were not attained, even on face-to-face testing. Patients with coexistent cognitive impairment performed worse than those who were cognitively normal.

Problems in using health survey questionnaires in older patients with physical disabilities. Can proxies be used to complete the SF-36?

BACKGROUND: The SF-36 Health Survey questionnaire has been proposed as a generic measure of health outcome. However, poor rates of return and high levels of missing data have been found in elderly subjects and, even with face-to-face interview, reliability and validity may still be disappointing, particularly in cognitively impaired patients. These patients may be the very patients whose quality of life is most affected by their illness and their exclusion will lead to biased evaluation of health status. A possible alternative to total exclusion is the use of a proxy to answer on the patient's behalf, but few studies of older people have systematically studied patient-proxy agreement. OBJECTIVE: To compare the agreement between patients, lay and professional proxies when assessing the health status of patients with the SF-36. METHODS: The SF-36 was administered by interview to 164 cognitively normal, elderly patients (Mini-mental State Examination 24 or more) referred for physical rehabilitation. The SF-36 was also completed by a patient-designated lay proxy (by post) and a professional proxy. Agreement between proxies and patients was measured by intraclass correlation coefficients (ICCs), and a bias index. RESULTS: Professional proxies were better able to predict the patients' responses than were the lay proxies. Criterion levels of agreement (ICC 0.4 or over) were attained for four of the eight dimensions of the SF-36 by professional proxies, but for only one dimension by lay proxies. In professional proxies, the magnitude of the bias was absent or slight (<0.2) for six of the eight dimensions of the SF-36 with a small (0.2-0.49) negative bias for the other two. Lay proxies showed a negative bias (i.e. they reported poorer function than did the patients themselves) for seven of the eight dimensions of the SF-36 (small in two and moderate (0.5-0.79) in five). CONCLUSIONS: For group comparisons using the SF-36, professional proxies might be considered when patients cannot answer reliably for themselves. However, in the present study, lay proxy performance on a postal questionnaire showed a strong tendency to negative bias. Further research is required to define the limitations and potentials of proxy completion of health status questionnaires.

Systematic review of the definition and measurement of anastomotic leak after gastrointestinal surgery.

BACKGROUND: Anastomotic leak after gastrointestinal surgery is an important postoperative event that leads to significant morbidity and mortality. Postoperative leak rates are frequently used as an indicator of the quality of surgical care provided. Comparison of rates between and within institutions depends on the use of standard definitions and methods of measurement of anastomotic leak. The aim of this study was to review the definition and measurement of anastomotic leak after oesophagogastric, hepatopancreaticobiliary and lower gastrointestinal surgery. METHODS: A systematic review was undertaken of the published literature. Searches were carried out on five bibliographical databases (Medline, Embase, The Cochrane Library, Cumulative Index for Nursing and Allied Health Literature and HealthSTAR) for English language articles published between 1993 and 1999. Articles were critically appraised by two independent reviewers and data on definition and measurement of anastomotic leak were extracted. RESULTS: Ninety-seven studies were reviewed and a total of 56 separate definitions of anastomotic leak were identified at three sites: upper gastrointestinal (13 definitions), hepatopancreaticobiliary (14) and lower gastrointestinal (29). The majority of studies used a combination of clinical features and radiological investigations to define and detect anastomotic leak. CONCLUSION: There is no universally accepted definition of anastomotic leak at any site. The definitions and values used to measure anastomotic failure vary extensively and preclude accurate comparison of rates between studies and institutions.

The measurement and monitoring of surgical adverse events.

BACKGROUND: Surgical adverse events contribute significantly to postoperative morbidity, yet the measurement and monitoring of events is often imprecise and of uncertain validity. Given the trend of decreasing length of hospital stay and the increase in use of innovative surgical techniques--particularly minimally invasive and endoscopic procedures--accurate measurement and monitoring of adverse events is crucial. OBJECTIVES: The aim of this methodological review was to identify a selection of common and potentially avoidable surgical adverse events and to assess whether they could be reliably and validly measured, to review methods for monitoring their occurrence and to identify examples of effective monitoring systems for selected events. This review is a comprehensive attempt to examine the quality of the definition, measurement, reporting and monitoring of selected events that are known to cause significant postoperative morbidity and mortality. METHODS - SELECTION OF SURGICAL ADVERSE EVENTS: Four adverse events were selected on the basis of their frequency of occurrence and likelihood of evidence of measurement and monitoring: (1) surgical wound infection; (2) anastomotic leak; (3) deep vein thrombosis (DVT); (4) surgical mortality. Surgical wound infection and DVT are common events that cause significant postoperative morbidity. Anastomotic leak is a less common event, but risk of fatality is associated with delay in recognition, detection and investigation. Surgical mortality was selected because of the effort known to have been invested in developing systems for monitoring surgical death, both in the UK and internationally. Systems for monitoring surgical wound infection were also included in the review. METHODS - LITERATURE SEARCH: Thirty separate, systematic literature searches of core health and biomedical bibliographic databases (MEDLINE, EMBASE, CINAHL, HealthSTAR and the Cochrane Library) were conducted. The reference lists of retrieved articles were reviewed to locate additional articles. A matrix was developed whereby different literature and study designs were reviewed for each of the surgical adverse events. Each article eligible for inclusion was independently reviewed by two assessors. METHODS - CRITICAL APPRAISAL: Studies were appraised according to predetermined assessment criteria. Definitions and grading scales were assessed for: content, criterion and construct validity; repeatability; reproducibility; and practicality (surgical wound infection and anastomotic leak). Monitoring systems for surgical wound infection and surgical mortality were assessed on the following criteria: (1) coverage of the system; (2) whether or not denominator data were collected; (3) whether standard and agreed definitions were used; (4) inclusion of risk adjustment; (5) issues related to data collection; (6) postdischarge surveillance; (7) output in terms of feedback and wider dissemination. RESULTS - SURGICAL WOUND INFECTION: A total of 41 different definitions and 13 grading scales of surgical wound infection were identified from 82 studies. Definitions of surgical wound infection varied from presence of pus to complex definitions such as those proposed by the Centres for Disease Control in the USA. A small body of literature has been published on the content, criterion and construct validity of different definitions, and comparisons have been made against wound assessment scales and multidimensional indices. There are examples of comprehensive hospital-based monitoring systems of surgical wound infection, mainly under the auspices of nosocomial surveillance. To date, however, there is little evidence of systematic measurement and monitoring of surgical wound infection after hospital discharge. RESULTS - ANASTOMOTIC LEAK: Over 40 definitions of anastomotic leak were extracted from 107 studies of upper gastrointestinal, hepatopancreaticobiliary and lower gastrointestinal surgery. No formal evaluations were found that assessed the validity or reliability of definitions or severity scales of anastomotic leak. One definition was proposed during a national consensus workshop, but no evidence of its use was found in the surgical literature. The lack of a single definition or gold standard hampers comparison of postoperative anastomotic leak rates between studies and institutions. RESULTS - DEEP VEIN THROMBOSIS: Although a critical review of the DVT literature could not be completed within the realms of this review, it was evident that a number of new techniques for the detection and diagnosis of DVT have emerged in the last 20 years. The group recommends a separate review be undertaken of the different diagnostic tests to detect DVT. RESULTS - SURGICAL MORTALITY MONITORING SYSTEMS: The definition of surgical mortality is relatively consistent between monitoring systems, but duration of follow-up of death postdischarge varies considerably. The majority of systems report in-hospital mortality rates; only some have the potential to link deaths to national death registers. Risk assessment is an important factor and there should be a distinction between recording pre-intervention factors and postoperative complications. A variety of risk scoring systems was identified in the review. Factors associated with accurate and complete data collection include the employment of local, dedicated personnel, simple and structured prompts to ensure that clinical input is complete, and accurate and automated data capture and transfer. CONCLUSIONS: The use of standardised, valid and reliable definitions is fundamental to the accurate measurement and monitoring of surgical adverse events. This review found inconsistency in the quality of reporting of postoperative adverse events, limiting accurate comparison of rates over time and between institutions. The duration of follow-up for individual events will vary according to their natural history and epidemiology. Although risk-adjusted aggregated rates can act as screening or warning systems for adverse events, attribution of whether events are avoidable or preventable will invariably require further investigation at the level of the individual, unit or department. CONCLUSIONS - RECOMMENDATIONS FOR RESEARCH: (1) A single, standard definition of surgical wound infection is needed so that comparisons over time and between departments and institutions are valid, accurate and useful. Surgeons and other healthcare professionals should consider adopting the 1992 Centers for Disease Control (CDC) definition for superficial incisional, deep incisional and organ/space surgical site infection for hospital monitoring programmes and surgical audits. There is a need for further methodological research into the performance of the CDC definition in the UK setting. (2) There is a need to formally assess the reliability of self-diagnosis of surgical wound infection by patients. (3) There is a need to assess formally the reliability of case ascertainment by infection control staff. (4) Work is needed to create and agree a standard, valid and reliable definition of anastomotic leak which is acceptable to surgeons. (5) A systematic review is needed of the different diagnostic tests for the diagnosis of DVT. (6) The following variables should be considered in any future DVT review: anatomical region (lower limb, upper limb, pelvis); patient presentation (symptomatic, asymptomatic); outcome of diagnostic test (successfully completed, inconclusive, technically inadequate, negative); length of follow-up; cost of test; whether or not serial screening was conducted; and recording of laboratory cut-off values for fibrinogen equivalent units. (7) A critical review is needed of the surgical risk scoring used in monitoring systems. (8) In the absence of automated linkage there is a need to explore the benefits and costs of monitoring in primary care. (9) The growing potential for automated linkage of data from different sources (including primary care, the private sector and death registers) needs to be explored as a means of improving the ascertainment of surgical complications, including death. This linkage needs to be within the terms of data protection, privacy and human rights legislation. (10) A review is needed of the extent of the use and efficiency of routine hospital data versus special collections or voluntary reporting.

The quality of measurement of surgical wound infection as the basis for monitoring: a systematic review.

Comparison of postoperative surgical wound infection rates between institutions and over time is only valid if standard, valid and reliable definitions are used. The aim of this review was to assess evidence of validity and reliability of the definition and measurement of surgical wound infection. A systematic review was undertaken of prospective studies of surgical wound infection published over a seven-year period; 1993-1999. The information extracted from individual studies included: definition of surgical wound infection; details of wound assessment scale, scoring or grading scale systems; and evidence of assessment of validity, reliability and feasibility of identified definitions and grading systems. Two independent reviewers appraised 112 prospective studies, 90 of which were eligible for inclusion; eight studies assessed validity and/or reliability. Forty-one different definitions of surgical wound infection were identified, five of which were 'standard' definitions proposed by multi-disciplinary groups. Presence of pus was the most frequently used single component of any definition; the CDC definitions of 1988 and 1992 were the most widely implemented standard definitions; and the ASEPSIS wound assessment scale was the most frequently used quantitative grading tool. Only two formal validations of a definition were found, and six studies of reliability. This review highlights the extent of variation in definition of surgical wound infection used in clinical practice, and the need for validation of both content and organization of a surveillance system. However, realistically, there will have to be a balance between the quality of the measurement and the practicality of surveillance.

Eliciting public preferences for healthcare: a systematic review of techniques.

BACKGROUND: Limited resources coupled with unlimited demand for healthcare mean that decisions have to be made regarding the allocation of scarce resources across competing interventions. Policy documents have advocated the importance of public views as one such criterion. In principle, the elicitation of public values represents a big step forward. However, for the exercise to be worthwhile, useful information must be obtained that is scientifically defensible, whilst decision-makers must be able and willing to use it. AIMS AND OBJECTIVES: The aim was to identify techniques that could be reasonably used to elicit public views on the provision of healthcare. Hence, the objectives were: (1) to identify research methods with the potential to take account of public views on the delivery of healthcare; (2) to identify criteria for assessing these methods; (3) to assess the methods identified according to the predefined criteria; (4) to assess the importance of public views vis-à-vis other criteria for setting priorities, as judged by a sample of decision-makers; (5) to make recommendations regarding the use of methods and future research. METHODS: A systematic literature review was carried out to identify methods for eliciting public views. Criteria currently used to evaluate such methods were identified. The methods identified were then evaluated according to predefined criteria. A questionnaire-based survey assessed the relative importance of public views vis-à-vis five other criteria for setting priorities: potential health gain; evidence of clinical effectiveness; budgetary impact; equity of access and health status inequalities; and quality of service. Two techniques were used: choice-based conjoint analysis and allocation of points technique. The questionnaire was sent to 143 participants. A subsample was followed up with a telephone interview. RESULTS: The methods identified were classified as quantitative or qualitative. RESULTS - QUANTITATIVE TECHNIQUES: Quantitative techniques, classified as ranking, rating or choice-based approaches, were evaluated according to eight criteria: validity; reproducibility; internal consistency; acceptability to respondents; cost (financial and administrative); theoretical basis; whether the technique offered a constrained choice; and whether the technique provided a strength of preference measure. Regarding ranking exercises, simple ranking exercises have proved popular, but their results are of limited use. The qualitative discriminant process has not been used to date in healthcare, but may be useful. Conjoint analysis ranking exercises did well against the above criteria. A number of rating scales were identified. The visual analogue scale has proved popular within the quality-adjusted life-year paradigm, but lacks constrained choice and may not measure strength of preference. However, conjoint analysis rating scales performed well. Methods identified for eliciting attitudes include Likert scales, the semantic differential technique, and the Guttman scale. These methods provide useful information, but do not consider strength of preference or the importance of different components within a total score. Satisfaction surveys have been frequently used to elicit public opinion. Researchers should ensure that they construct sensitive techniques, despite their limited use, or else use generic techniques where validity has already been established. Service quality (SERVQUAL) appears to be a potentially useful technique and its application should be researched. Three choice-based techniques with a limited application in healthcare are measure of value, the analytical hierarchical process and the allocation of points technique, while those more widely used, and which did well against the predefined criteria, include standard gamble, time trade-off, discrete choice conjoint analysis and willingness to pay. Little methodological work is currently available on the person trade-off. RESULTS - QUALITATIVE TECHNIQUES: Qualitative techniques were classified as either individual or group-based approaches. Individual approaches included one-to-one interviews, dyadic interviews, case study analyses, the Delphi technique and complaints procedures. Group-based methods included focus groups, concept mapping, citizens' juries, consensus panels, public meetings and nominal group techniques. Six assessment criteria were identified: validity; reliability; generalisability; objectivity; acceptability to respondents; and cost. Whilst all the methods have distinct strengths and weaknesses, there is a lot of ambiguity in the literature. Whether to use individual or group methods depends on the specific topic being discussed and the people being asked, but for both it is crucial that the interviewer/moderator remains as objective as possible. The most popular and widely used such methods were one-to-one interviews and focus groups. (ABSTRACT TRUNCATED)

Independent nursing practice: a national survey of attitudes of practice employed nurses in Scotland.

BACKGROUND: During the last decade, the number of practice nurses has increased dramatically and their role has evolved according to demand rather than through planning and design. Consequently, many nursing roles have become extended and nurses now perform many of the tasks previously performed by doctors. With increasing emphasis on primary care, their new role has become widely accepted and continues to develop. There is now a real question as to whether, with suitable training, it is timely to consider a formal extension to independent practice for at least some practice nurses. OBJECTIVE: The aim was to describe the characteristics of practice nurses and to explore their attitudes to independent practice. For the purpose of this study, independent practice was taken to mean specialised autonomous practice. DESIGN: This was a descriptive, cross-sectional study undertaken by postal questionnaire. A two stage sampling process was used. SETTING: Firstly a 1/2 sample of all general practices in Scotland (n = 625) was asked for the names of all practice employed nurses. Secondly, one practice nurse from each practice was sent a postal questionnaire. RESULTS: Five hundred and thirty eight general practices responded. Eighty six practices had no practice employed nurse. Four hundred and thirty three practices (96%; 433/452) were willing to allow their practice nurses to be approached to take part in the study. Four hundred practice nurses returned questionnaires (92%; 400/433). Fifteen were excluded because the nurses were not fully practice employed. Three hundred and eighty five were suitable for inclusion in the study (85%; 385/452). Most practice nurses were over 35 years of age and had been in post for more than three years. Almost half had at least one other nursing qualification in addition to registration. Eighty six percent thought that there should be independent practice for some nurses within the profession and 65% would, themselves, be happy to practise independently. CONCLUSION: Most practice nurses throughout Scotland think that there should be independent practice for some nurses.

Needs assessment: taking stock.

In 1994, the Scottish Needs Assessment Programme (SNAP) carried out a stocktaking review of all needs assessment reports in 14 topic areas produced in Scotland on the previous three years. National needs assessment documents from England in the relevant topic areas were also reviewed. The review identified two particular points for comment. First, in respect of content, the definition of need as "the ability to benefit'-while appropriate for NHS purchasing- must be balanced by a greater emphasis on the wider concerns for the public's health. At the same time, relevant economic and costing information should be incorporated. Secondly, the process of information collation for purchasing could be made more efficient. Closer links between clinical experts and public health specialists would ensure assessments based on timely opportunities for change. National reviews should provide generally applicable intelligence and comparative analyses; short local reports can then focus on local quantification and priority setting.

Needs assessment in Scotland: collaboration in public health.

The National Health Service reforms revitalized the national emphasis on the public's health and health needs assessment. In Scotland, in contrast with England, there was no central investment in the development of methods and programmes for needs assessment in the context of the new NHS. To achieve a concerted effort, therefore, a self-help network--the Scottish Needs Assessment Programme (SNAP)--was created by the Scottish Forum for Public Health Medicine. This paper describes its evolution to the point where it is now supported as part of a national network of information for purchasing.

Psychological aspects of recurrent chest pain.

Of 113 consecutive patients admitted recurrently with chest pain 28% exhibited psychiatric morbidity using the GHQ-28 (General Health Questionnaire). Eighty patients had ischaemic heart disease, 17 had non-specific pain and 13 were excluded because of other organic causes for their pain. Of the non-specific group, seven had been admitted previously with chest pain. In common with previous studies of first admissions with non-specific chest pain, recurrent admissions were younger and predominantly male. They also had a history of greater alcohol and cigarette use than patients with ischaemic heart disease. Greater psychiatric morbidity was not demonstrated in this small group of patients. In spite of the absence of an organic aetiology, patients with non-specific pain showed similar rates of re-admission to those with ischaemic heart disease before and after the study. Further research is indicated to identify aetiological and maintaining factors for continued non-specific pain.

The effects of dentine bonding agents on marginal leakage of composite restorations.

The aim of this study was to compare the effects upon marginal leakage of a number of dentine bonding agents: Gluma, Scotchbond, Topaz and an experimental material when used with a posterior composite resin, Occlusin. The results were also compared with composite used without a dentine bonding agent and with a glass ionomer, Chemfil II. Class V cavities with or without a bevelled cavo-surface margin were prepared in the buccal surfaces of extracted premolar teeth. Following restoration, the teeth were stored for periods of up to 3 months and then thermally cycled. Marginal leakage was subsequently determined using a radioactive isotope containing 45Ca, and an autoradiographic technique. Image analysis was used to determine the total amount of linear leakage for each specimen. The results showed that some leakage occurred for all materials at each time interval. The bevelled design of cavity allowed significantly less leakage than the non-bevelled type. The use of dentine bonding agents did not improve the marginal seal of the composite restorations, and the glass ionomer restorations showed significantly less leakage than the composite resin and dentine bonding agent combinations.

Measuring outcome of diabetes: a retrospective survey.

The feasibility of using hospital discharge data to monitor six outcome indicators for diabetes care was assessed by reviewing retrospectively the occurrence of these events recorded in hospital records. The population studied was that of the Orkney Islands (19,500) over a 10-year period (1976-1985). During that time, 230 Orkney diabetic patients were treated in Orkney and/or Aberdeen hospitals. The six outcome indicators were: hospital admission rates for diabetic patients (609 in 230 patients), hospital admission rates specifically for diabetic ketoacidosis (29 in 20 patients), rates of diabetes-related lower limb amputations (36 in 23 patients), perinatal mortality rates related to maternal diabetes (nil), visual loss or blindness (13 eyes in 9 patients) and end-stage renal failure (one patient). Scottish Morbidity Returns (which collect data similar to that in the Hospital In-patient Enquiry in England) were shown by case note review to underestimate these outcomes by 41%. Cardiovascular disease, cerebrovascular disease, and peripheral vascular disease accounted for half of all in-patient bed use by diabetic patients (6077 of 13,951 days). The routinely available Scottish hospital discharge data, which are collected for a different purpose, are not sufficiently accurate or complete to reflect variations in actual diabetic events.

Outcome indicators: who benefits?

Most of the recent work on performance indicators has concentrated on the provision or activities of health services rather than on their impact on the patients and populations who use them. Although the precise relationship between treatment and outcome is often unclear, simple examination of routinely available data can show whether mortality and morbidity are changing in desired directions. This pinpoints topics for more detailed professional review. It is incumbent on doctors to match the concern over the efficient use of health services with information about their effects on people's health.