Introduction The Nominal Group Technique (NGT) and Delphi Technique are consensus methods used in research that is directed at problem-solving, idea-generation, or determining priorities. While consensus methods are commonly used in health services literature, few studies in pharmacy practice use these methods. This paper provides an overview of the NGT and Delphi technique, including the steps involved and the types of research questions best suited to each method, with examples from the pharmacy literature. Methodology The NGT entails face-to-face discussion in small groups, and provides a prompt result for researchers. The classic NGT involves four key stages: silent generation, round robin, clarification and voting (ranking). Variations have occurred in relation to generating ideas, and how ‘consensus’ is obtained from participants. The Delphi technique uses a multistage self-completed questionnaire with individual feedback, to determine consensus from a larger group of ‘experts.’ Questionnaires have been mailed, or more recently, e-mailed to participants. When to use The NGT has been used to explore consumer and stakeholder views, while the Delphi technique is commonly used to develop guidelines with health professionals. Method choice is influenced by various factors, including the research question, the perception of consensus required, and associated practicalities such as time and geography. Limitations The NGT requires participants to personally attend a meeting. This may prove difficult to organise and geography may limit attendance. The Delphi technique can take weeks or months to conclude, especially if multiple rounds are required, and may be complex for lay people to complete.

Prescribing errors affect patient safety throughout hospital practice. Previous reviews of studies have often targeted specific populations or settings, or did not adopt a systematic approach to reviewing the literature. Therefore, we set out to systematically review the prevalence, incidence and nature of prescribing errors in hospital inpatients. MEDLINE, EMBASE, CINAHL and International Pharmaceutical Abstracts (all from 1985 to October 2007) were searched for studies of prescriptions for adult or child hospital inpatients giving enough data to calculate an error rate. Electronic prescriptions and errors for single diseases, routes of administration or types of prescribing error were excluded, as were non-English language publications. Median error rate (interquartile range [IQR]) was 7% (2-14%) of medication orders, 52 (8-227) errors per 100 admissions and 24 (6-212) errors per 1000 patient days. Most studies (84%) were conducted in single hospitals and originated from the US or UK (72%). Most errors were intercepted and reported before they caused harm, although two studies reported adverse drug events. Errors were most common with antimicrobials and more common in adults (median 18% of orders [ten studies, IQR 7-25%]) than children (median 4% [six studies, IQR 2-17%]). Incorrect dosage was the most common error. Overall, it is clear that prescribing errors are a common occurrence, affecting 7% of medication orders, 2% of patient days and 50% of hospital admissions. However, the reported rates of prescribing errors varied greatly and this could be partly explained by variations in the definition of a prescribing error, the methods used to collect error data and the setting of the study. Furthermore, a lack of standardization between severity scales prevented any comparison of error severity across studies. Future research should address the wide disparity of data-collection methods and definitions that bedevils comparison of error rates or meta-analysis of different studies.

To determine the extent to which adverse drug reactions (ADRs) in elderly patients admitted to hospital are due to inappropriate prescribing, we examined 416 successive admissions of elderly patients to a teaching hospital. Interacting drug combinations and drugs with relative contra-indications (CIs) were common, but not as important in producing ADRs as drugs with absolute CIs or unnecessary drugs. Forty-eight patients (11.5% of admissions) were taking a total of 51 drugs with absolute CIs (3.8% of prescriptions). One hundred and seventy-five drugs were discontinued on or shortly after admission in 113 (27%) patients because they were deemed to be unnecessary. One hundred and three patients (27.0% of those on medication) experienced 151 ADRs of which 75 (49.7%) were due to drugs with absolute CIs and/or that were unnecessary, a significantly higher rate of ADRs (p less than 0.001) than observed for all prescriptions. Of 26 (6.3%) admissions attributed to ADRs, 13 (50%) were due to inappropriate prescriptions. The admission rate per prescription was significantly higher (p less than 0.001) for inappropriate than for appropriate drugs. We conclude that much drug-related morbidity in the elderly population may be avoidable, as it is due to inappropriate prescribing.

Prescribing errors are common, they result in adverse events and harm to patients and it is unclear how best to prevent them because recommendations are more often based on surmized rather than empirically collected data. The aim of this systematic review was to identify all informative published evidence concerning the causes of and factors associated with prescribing errors in specialist and non-specialist hospitals, collate it, analyse it qualitatively and synthesize conclusions from it. Seven electronic databases were searched for articles published between 1985-July 2008. The reference lists of all informative studies were searched for additional citations. To be included, a study had to be of handwritten prescriptions for adult or child inpatients that reported empirically collected data on the causes of or factors associated with errors. Publications in languages other than English and studies that evaluated errors for only one disease, one route of administration or one type of prescribing error were excluded. Seventeen papers reporting 16 studies, selected from 1268 papers identified by the search, were included in the review. Studies from the US and the UK in university-affiliated hospitals predominated (10/16 [62%]). The definition of a prescribing error varied widely and the included studies were highly heterogeneous. Causes were grouped according to Reason's model of accident causation into active failures, error-provoking conditions and latent conditions. The active failure most frequently cited was a mistake due to inadequate knowledge of the drug or the patient. Skills-based slips and memory lapses were also common. Where error-provoking conditions were reported, there was at least one per error. These included lack of training or experience, fatigue, stress, high workload for the prescriber and inadequate communication between healthcare professionals. Latent conditions included reluctance to question senior colleagues and inadequate provision of training. Prescribing errors are often multifactorial, with several active failures and error-provoking conditions often acting together to cause them. In the face of such complexity, solutions addressing a single cause, such as lack of knowledge, are likely to have only limited benefit. Further rigorous study, seeking potential ways of reducing error, needs to be conducted. Multifactorial interventions across many parts of the system are likely to be required.