Adjusted antibiotic prescribing in primary care by the NHS - WMCA

Annual total number of prescribed antibiotic items per STAR PU (Specific Therapeutic group Age sex weightings Related Prescribing Unit) ## Rationale Reductions in antibiotic consumption is a well-recognised target in Anti-Microbial Resistance (AMR) policies across UKHSA, the NHS, DHSC and internationally, including WHO. This can be used as an overall metric for benchmarking across Local Authorities, bringing together a whole health economy approach with NHS prescriptions from all types of hospitals (including Acute, Mental Health, Community etc), General Practices, other Community Locations (Urgent care, Walk in Centres). Data from Dentists is only available at NHS area team at present but will be added to this metric when available. In order to fully appreciate antimicrobial prescribing, it is necessary to take into consideration demographic characteristics of the population as it may influence levels of prescribing. For that reason STAR PU data is adjusted for both age and sex. STAR PU is an adjusted rate that removes confounding effects of age and sex in the comparison of prescribing between different geographical areas. This method allows for more accurate comparison of prescribing. In this specific indicator, a higher value is associated with increased prescribing. ## Definition of numerator "Total number of antibiotic items prescribed in practices located within the area. An item is an antibiotic (from British National Formulary Section 5.1) that is prescribed in a primary care setting. A prescription item refers to a single item prescribed by a prescriber on a prescription form (known as an FP10). If a prescription form includes three medicines it is counted as three prescription items. The number of items is a measure of how often a prescriber has decided to write a prescription. It is often used when we wish to look at prescriber behaviour as every prescription is an opportunity to change treatment. For vaccinations and acute treatment (for example, a short course of antibiotics) the item is also a reasonable measure of the number of courses of treatment. GP practice counts of items are aggregated to Local Authorities based on the postcode of location of the GP practice." ## Definition of denominator Total of STAR PU units for practices located within the area. STAR PU are weighted units to allow comparisons adjusting for the age and sex of patients distribution of each practice. These variables vary significantly and it is important to make necessary adjustments. There are differences in the age and sex profiles of patients who are prescribed drugs in specific therapeutic groups. For example: drugs for dementia are generally prescribed for older people. STAR PUs (Specific Therapeutic Group Age sex weightings Related Prescribing Units) allow more accurate and meaningful comparisons within a specific therapeutic group by taking into account the types of people who will be receiving that treatment. These have been developed to weight individual practice or organisation populations for age and sex to allow for better comparison of prescribing patterns. These figures are based on the cost or volume of prescribing within therapeutic groups rather than all prescribing. The STAR PU weightings for anti bacterials are item based, as this is more appropriate for such prescribing. These weightings should be used only for the specific therapeutic area. STAR PU values are available for BNF sections from the [https://digital.nhs.uk/data-and-information/areas-of-interest/prescribing] NHS Digital website ## Caveats All antibiotic items that are administered orally, which are prescribed in a primary care setting are recorded by NHS Digital. There are no concerns about incomplete or inaccurate data. STAR PU data is inappropriate to use at any smaller level than total prescribing. I.e. individual drug class level. STAR PU data only includes antibiotics that are administered orally. Orally administered derivative of BNF 5.1 codes account for more than 99.8 percent of all prescribed items. Drugs are only included in the numerator if they have a British National Formulae (BNF) 5.1 code consistant with an anti bacterial item. Figures will vary if compared to similar indicators at different geographical levels for example GP, as they are separate indicators and have different criteria for inclusion and exclusion.