Static outliers for Cornerways Surgery

There is substantial variation in prescribing behaviours, across various different areas of medicine. Some variation can be explained by demographic changes, or local policies or guidelines, but much of the remaining variation is less easy to explain. At OpenPrescribing we are piloting a number of data-driven approaches to identify unusual prescribing and collect feedback on this prescribing to inform development of new tools to support prescribers and organisations to audit and review prescribing.

This report has been developed to automatically identify prescribing patterns at a chemical level which are furthest away from “typical prescribing” and can be classified as an “outlier”. We calculate the number of prescriptions for each chemical in the BNF coding system using the BNF subparagraph as a denominator, for prescriptions dispensed between April 2021 and August 2021. We then calculate the mean and standard deviation for each numerator and denominator pair across all practices/CCGs/PCNs/STPs. From this we can calculate the “z-score”, which is a measure of how many standard deviations a given practice/CCG/PCN/STP is from the population mean. We then rank your “z-scores” to find the top 5 results where prescribing is an outlier for prescribing higher than its peers and those where it is an outlier for prescribing lower than its peers.

It is important to remember that this information was generated automatically and it is therefore likely that some of the behaviour is warranted. This report seeks only to collect information about where this variation may be warranted and where it might not. Our full analytical method code is openly available on GitHub here.

The DataLab is keen to hear your feedback on the results. You can do this by completing the following survey or emailing us at ebmdatalab@phc.ox.ac.uk. Please DO NOT INCLUDE IDENTIFIABLE PATIENT information in your feedback. All feedback is helpful, you can send short or detailed feedback.

Prescribing where Cornerways Surgery is higher than most

BNF Chemical Chemical Items BNF Subparagraph Subparagraph Items Ratio Mean std Z_Score Plots
Gluten free/low protein drink 4 Foods for special diets 43 0.09 0.00 0.00 64.91
Chloral hydrate 12 Hypnotics 103 0.12 0.00 0.01 17.34
Empagliflozin/linagliptin 3 Other antidiabetic drugs 227 0.01 0.00 0.00 10.69
Clemastine fumarate 1 Antihistamines 294 0.00 0.00 0.00 6.72
Dicycloverine hydrochloride 6 Antispasmodic and other drugs altering gut motility 65 0.09 0.01 0.01 6.41

Prescribing where Cornerways Surgery is lower than most

BNF Chemical Chemical Items BNF Subparagraph Subparagraph Items Ratio Mean std Z_Score Plots
Furosemide 225 Loop diuretics 471 0.48 0.86 0.09 -4.23
Hydrocortisone 28 Topical corticosteroids 238 0.12 0.34 0.06 -3.47
Midazolam hydrochloride 0 Drugs used in status epilepticus 1 0.00 0.79 0.30 -2.62
Spironolactone 52 Potassium-sparing diuretics and aldosterone antagonists 138 0.38 0.72 0.14 -2.49
Amlodipine 493 Calcium-channel blockers 1038 0.47 0.75 0.11 -2.46