An experimental study of determinants of the extent of disagreement within clinical guideline development groups

OBJECTIVE

To assess the effect of design features and clinical and social cues on the extent of disagreement among participants in a formal consensus development process.

METHODS

Factorial design involving 16 groups consisting of 135 general practitioners (GPs) and 42 mental health professionals from England. The groups rated the appropriateness of four mental health interventions for three conditions (chronic back pain, irritable bowel syndrome, and chronic fatigue syndrome) in the context of various clinical and social cues. The groups differed in three design features: provision of a systematic literature review (versus not provided), group composition (mixed versus GP only), and assumptions about the healthcare resources available (realistic versus idealistic). Disagreement was measured using the mean absolute deviation from a group's median rating for a scenario.

RESULTS

None of the design features significantly affected the extent of disagreement within groups (all p>0.3). Disagreement did differ between treatments (closer consensus for cognitive behavioural therapy and behavioural therapy than for brief psychodynamic intervention therapy and antidepressants) and cues (closer consensus for depressed patients and patients willing to try any treatment).

CONCLUSION

In terms of the extent of disagreement in the groups in this study, formal consensus development was a robust technique in that the results were not dependent on the way it was conducted.

A case of infant botulism with a possible link to infant formula milk powder: evidence for the presence of more than one strain of Clostridium botulinum in clinical specimens and food

Infant botulism was confirmed in a 5-month-old female by both isolation of Clostridium botulinum type B and by detection of type B botulinum neurotoxin in rectal washout and faeces. DNA fingerprinting of nine isolates from faeces yielded two different amplified-fragment length polymorphism (AFLP) patterns. C. botulinum was isolated from two of 14 food and drink items from the patient's home: C. botulinum type A was recovered from an opened container of dried rice pudding and C. botulinum type B from opened infant formula milk powder. Ten C. botulinum type B isolates from the opened infant formula yielded four AFLP patterns, two of which were indistinguishable from the clinical isolates. Fifteen unopened foods were tested and C. botulinum type B of a unique AFLP pattern was recovered from one unopened infant formula of the same batch as the opened container. It is suggested that multiple C. botulinum were present in both food and the intestine during infant botulism.

Grommets in otitis media with effusion: an individual patient data meta-analysis

AIMS

To identify subgroups of children with otitis media with effusion (OME) that might benefit more than others from treatment with ventilation tubes.

METHODS

An individual patient data (IPD) meta-analysis on seven randomised controlled trials (n = 1234 children in all), focusing on interactions between treatment and baseline characteristics--hearing level (HL), history of acute otitis media, common colds, attending day-care, gender, age, socioeconomic status, siblings, season, passive smoking, and history of breast feeding. Outcome measures that could be studied were mean time spent with effusion (n = 557), mean hearing levels (n = 557 in studies that randomised children, and n = 180 in studies that randomised ears), and language development (n = 381).

RESULTS

In the trials that treated both ears the only significant interaction was between day-care and surgery, occurring where mean hearing level was the outcome measure. None of the other baseline variables showed an interaction effect with treatment that would justify subgrouping. In the trials that treated only one ear, the baseline hearing level showed a significant but not pervasive interaction with treatment-that is, only with a cut-off of 25 dB HL.

CONCLUSIONS

The effects of conventional ventilation tubes in children studied so far are small and limited in duration. Observation (watchful waiting) therefore seems to be an adequate management strategy for most children with OME. Ventilation tubes might be used in young children that grow up in an environment with a high infection load (for example, children attending day-care), or in older children with a hearing level of 25 dB HL or greater in both ears persisting for at least 12 weeks.

Directory of clinical databases: improving and promoting their use

BACKGROUND

The controversy surrounding the actual and potential use of clinical databases partly reflects the huge variation in their content and quality. In addition, use of existing clinical databases is severely limited by a lack of knowledge of their availability.

OBJECTIVES

To develop and test a standardised method for assessing the quality (completeness and accuracy) of clinical databases and to establish a web based directory of databases in the UK.

METHODS

An expert group was set up (1). to establish the criteria for inclusion of databases; (2). to develop a quality assessment instrument with high content validity, based on epidemiological theory; (3). to test empirically, modify, and retest the acceptability to database custodians, face validity and floor/ceiling effects; and (4). to design a website.

RESULTS

Criteria for inclusion of databases were the provision of individual level data; inclusion in the database defined by a common circumstance (e.g. condition, treatment), an administrative arrangement, or an adverse outcome; and inclusion of data from more than one provider. A quality assessment instrument consisting of 10 items (four on coverage, six on reliability and validity) was developed and shown to have good face and content validity, no floor/ceiling effects, and to be acceptable to database custodians. A website (www.docdat.org) was developed. Indications over the first 18 months (number of visitors to the site) are that it is increasingly popular. By November 2002 there were around 3500 hits a month.

CONCLUSIONS

A website now exists where visitors can identify clinical databases in the UK that may be suitable to meet their aims. It is planned both to develop a local version for use within a hospital and to encourage similar national systems in other countries.

A national census of Irish general practice training programme graduates 1990-1996

We followed the career pathways of all graduates of Irish general practice training schemes between 1990 and 1996 inclusive, with specific reference to their current positions, ten year aspirations, perceived barriers to their ideal career and attitudes to out of hours work. A postal survey using a structured questionnaire was performed. Addresses were identified for 253 of the 266 graduates (95%). A total of two hundred and nine responses were received (84% of those with an identifiable address). 173 (83%) have remained in general practice; 90% in Ireland and 60% in the same health board of their training programme. The preferred career option for 79% was to be a general practice principal; this differed significantly between males (89%) and females (74%) (p=0.016). Being a single-handed general practitioner was the preferred option for 2%; 43% considered this unacceptable. A half would prefer to work in a country town; one third considered a rural location as unacceptable. 'Out of hours' commitment and availability of local posts were the most commonly perceived barriers to career progress (53% and 45% respectively). 26% were not prepared to do any out of hours work; this differed significantly between males (10%) and females (30%) (p<.001). 17% have permanently left a career in general practice. Female general practitioners were not significantly more likely than male general practitioners to have left (19% vs. 14%, p=0.3). The most common reason given for leaving general practice was other career interest (78%). The significant increase in female general practice graduates over the past twenty years is highlighted. The vast majority of these female graduates wished to be a principal in a group practice and were prepared to undertake out of hours work. There is also a mismatch between career aspirations and the present structure of general practice in Ireland. The urgent need for changes in health system organisation to ensure that these intentions can be fulfilled is emphasised.

Reduction in the use of surgery for glue ear: did national guidelines have an impact?

BACKGROUND

It is widely accepted that the passive dissemination of national clinical guidance has little or no impact on practice.

OBJECTIVE

To assess the impact in England of an Effective Health Care bulletin on childhood surgery for glue ear issued in 1992 and to understand the reasons for any change (or lack of change) in practice that ensued.

METHOD

Time series analysis of the rate of use of surgery by children under 10 years of age from 1975 to 1997/8 in 13 English health districts.

RESULTS

Following a rise in the rate of surgery in public (National Health Service) hospitals from 1975 to 1985, the rate declined by 1.6% a year from 1986 to 1992/3. Following publication of the guidelines in November 1992, the rate of decline increased to 10.1% a year. Even after allowing for a slight increase in the use of independent (private) hospitals between 1992/3 and 1997/8, the overall rate of decline was at least 7.9%. It appears that the rate of referral of cases by primary care physicians (general practitioners) halved during this period. Several contextual factors are thought to have contributed to the effect of the guidelines, including pre-existing professional concern about the value of surgery, the introduction of an internal market into the NHS, and growing apprehension among parents fuelled by scepticism in the mass media. During this unprecedented period of rapid change in usage, staff delivering the service remained unaware of the alterations in their own practice.

CONCLUSIONS

Passive dissemination of national guidelines can accelerate an existing trend in clinical practice if the context is hospitable. Policy makers should identify and target such situations.

Influence of patient gender on admission to intensive care

STUDY OBJECTIVES

To compare the case mix and outcomes of male and female patients admitted to intensive care units for a wide range of conditions.

DESIGN

Cross sectional study of prospectively collected data.

SETTING

The Intensive Care National Audit and Research Centre, (ICNARC) Case Mix Programme.

PARTICIPANTS

46 587 admissions to 91 units across England, Wales, and Northern Ireland.

MAIN RESULTS

No gender differences were found in case mix on admission or in mortality for five conditions (cardiac arrhythmia, chronic obstructive airways disease, asthma, self poisoning, and seizures). There was some evidence of horizontal and vertical inequity for female patients with myocardial infarction and with neurological bleeding. Vertical equity was not achieved for male pneumonia and ventricular failure patients and for women with primary brain injury.

CONCLUSIONS

This study demonstrated, for the first time, possible inequitable use of intensive care for patients with certain conditions. This may be secondary to gender bias and can result in either over-treatment in the favoured group, or under-treatment in the neglected group. It would therefore be pertinent to re-examine these findings using other databases, and to further investigate the causative factors, including gender bias.

Outbreak of tuberculosis at a Newcastle public house: the role and effectiveness of contact screening

We report an outbreak of tuberculosis (TB) that originated in a public house, involving 12 cases. The presumed index case was a regular patron. Initial screening of close contacts identified no further cases. Six cases of TB then presented symptomatically among other regular patrons. Contact screening was extended to include all regular patrons and bar staff. In total, 110 individuals were screened. One case was detected and three children were placed on chemoprophylaxis. Transmission of M. tuberculosis between patrons of a public house may cause community outbreaks of TB. Where cases present outside a close-contact screening program, extended contact screening must be considered.

Patient determinants of mental health interventions in primary care

BACKGROUND

A large proportion of a general practitioner's (GP's) caseload comprises patients with mental health problems. It is important to ensure that care is provided appropriately, on the basis of clinical need. It is therefore necessary to investigate the determinants of the use of mental health care in the primary care sector and, in particular, to identify any non-clinical characteristics of patients that affect the likelihood of their receiving appropriate care.

AIM

To identify and compare the influence of non-clinical patient factors on GPs' acknowledgement of mental problems and on their provision of mental health care.

METHOD

Cross sectional study of adults aged 16 to 65 years old (n = 802) attending one of eight practices (20 GPs in total) in inner west London.

RESULTS

Multivariable analysis showed that the combination of factors that best predict GPs' acknowledgement of the presence of mental problems are general health questionnaire (GHQ) scores (odds ratio [OR] = 1.10 per unit increase in score, 95% confidence interval [CI] = 1.07 to 1.13), previous mental symptoms (OR = 7.5, 95% CI = 4.3 to 12.9), increasing age (OR = 1.03 per one-year increase, 95% CI = 1.01 to 1.04) and physical health status (OR = 0.98 per unit increase in short form-36 (SF-36) score, 95% CI = 0.96 to 1.00). Multivariable analysis showed that the combination of factors that best predict intervention (prescription for psychotropic medication; return visit to GP; referral to psychiatric inpatients/outpatients; referral to other [specified] health professionals, or social services) are previous symptoms (OR = 7.4, 95% CI = 3.8 to 14.4), white ethnic group (OR = 2.2, 95% CI 0.9 to 5.5); and not owning a property (OR = 2.1, 95% CI = 1.1 to 4.0). Life events influenced intervention only in the presence of low GHQ scores (OR = 8.1, 95% CI = 2.7 to 24.0).

CONCLUSIONS

Mental problems are common in primary care and their acknowledgement is a necessary but not a sufficient condition for intervention. Our results show that GPs' decisions about mental health interventions can be influenced by non-clinical patient factors, regardless of patients' clinical needs. The results suggest that current practice may not always be equitable, and point to the need for better understanding of the basis of these potential inequalities and for focused training.

Use of consensus development to establish national research priorities in critical care

OBJECTIVES

To test the feasibility of using a nominal group technique to establish clinical and health services research priorities in critical care and to test the representativeness of the group's views.

DESIGN

Generation of topics by means of a national survey; a nominal group technique to establish the level of consensus; a survey to test the representativeness of the results.

SETTING

United Kingdom and Republic of Ireland.

SUBJECTS

Nominal group composed of 10 doctors (8 consultants, 2 trainees) and 2 nurses.

MAIN OUTCOME MEASURE

Level of support (median) and level of agreement (mean absolute deviation from the median) derived from a 9 point Likert scale.

RESULTS

Of the 325 intensive care units approached, 187 (58%) responded, providing about 1000 suggestions for research. Of the 106 most frequently suggested topics considered by the nominal group, 37 attracted strong support, 48 moderate support and 21 weak support. There was more agreement after the group had met-overall mean of the mean absolute deviations from the median fell from 1.41 to 1.26. The group's views represented the views of the wider community of critical care staff (r=0.73, P<0.01). There was no significant difference in the views of staff from teaching or from non-teaching hospitals. Of the 37 topics that attracted the strongest support, 24 were concerned with organisational aspects of critical care and only 13 with technology assessment or clinical research.

CONCLUSIONS

A nominal group technique is feasible and reliable for determining research priorities among clinicians. This approach is more democratic and transparent than the traditional methods used by research funding bodies. The results suggest that clinicians perceive research into the best ways of delivering and organising services as a high priority.

Improving clinical decision support through case-based data fusion

This paper presents an information fusion technique based on a knowledge discovery model, and the case-based reasoning decision framework. Using signal data and database records from the heart disease risk estimation domain, three data fusion methods are discussed. Two of these methods combine information at the retrieval-outcome level, and one method merges data at the discovery-input level. The result of these three models are compared and evaluated against the performance of single-source models. It is shown that the methods that fuse information at the retrieval-outcome level are significantly superior.

Consensus development methods: a review of best practice in creating clinical guidelines

BACKGROUND

Although there is debate about the appropriate place of guidelines in clinical practice, guidelines can be seen as one way of assisting clinicians in decision-making. Given the likely diversity of opinion that any group of people may display when considering a topic, methods are needed for organising subjective judgements. Three principal methods (Delphi, nominal group technique, consensus development conference) exist which share the common objective of synthesising judgements when a state of uncertainty exists.

OBJECTIVES

To identify the factors that shape and influence the clinical guidelines that emerge from consensus development methods and to make recommendations about best practice in the use of such methods.

METHODS

Five electronic databases were searched: Medline (1966-1996), PsychLIT (1974-1996), Social Science Citation Index (1990-1996), ABI Inform and Sociofile. From the searches and reference lists of articles a total of 177 empirical and review articles were selected for review.

RESULTS

The output from consensus development methods may be affected by: the way the task is set (choice of cues, recognition of contextual cues, the focus of the task, the comprehensiveness of the scenarios); the selection of participants (choice of individuals, degree of homogeneity of the group, their background, their number); the selection and presentation of scientific information (format, extent to which its quality and content is assessed); the way any interaction is structured (number of rating rounds, ensuring equitable participation, physical environment for meetings); and the method of synthesising individual judgements (definition of agreement, rules governing outliers, method of mathematical aggregation).

CONCLUSIONS

Although a considerable amount of research has been carried out, many aspects have not been investigated sufficiently. For the time being at least, advice on those aspects has, therefore, to be based on the user's own commonsense and the experience of those who have used or participated in these methods. Even in the long term, some aspects will not be amenable to scientific study. Meanwhile, adherence to best practice will enhance the validity, reliability and impact of the clinical guidelines produced.