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Prototype Prescribing Outlier Dashboard for Croydon Gp Super Network PCN

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. These pilot results are provided for the interest of advanced users, although we don't know how relevant they are in practice. 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.

The DataLab is keen to hear your feedback on the results. You can do this by completing the following survey or emailing us at [email protected]. Please DO NOT INCLUDE IDENTIFIABLE PATIENT information in your feedback. All feedback is helpful, you can send short or detailed feedback.

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, the count of all prescriptions within that chemical's BNF subparagraph, for prescriptions dispensed between June 2021 and December 2021. We then calculate the ratio of these counts along with the mean and standard deviation of those ratios across all PCNs. From this we can calculate the “z-score”, which is a measure of how many standard deviations a given PCN is from the population mean. We then rank your “z-scores” to find the top 10 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.

For each outlier chemical, a kernel density estimation plot of all PCN's chemical:subparagraph ratios is provided, with this PCN's ratio overlaid in red.

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, to inform research on this topic. Our full analytical method code is openly available on GitHub here.

This is a new, experimental feature. We'd love to .

Prescribing where Croydon Gp Super Network PCN is higher than most

BNF Chemical Chemical Items BNF Subparagraph Subparagraph Items Ratio Mean std Z_Score Plots
Oxitriptan 4 Other antidepressant drugs 10,060 0.00 0.00 0.00 9.71
Iron and folic acid 102 Oral iron 4,683 0.02 0.00 0.00 6.60
Moxifloxacin 31 Quinolones 284 0.11 0.01 0.02 6.22
Doxepin hydrochloride 22 Topical local anaesthetics and antipruritics 129 0.17 0.01 0.03 5.93
Strontium ranelate 14 Bisphosphonates and other drugs 3,187 0.00 0.00 0.00 5.09
Ergocalciferol 255 Vitamin D 15,016 0.02 0.00 0.00 4.67
Promethazine teoclate 109 Drugs used in nausea and vertigo 3,110 0.04 0.00 0.01 4.48
Diethylamine salicylate 436 Rubefacients, topical NSAIDS, capsaicin and poultice 2,607 0.17 0.02 0.04 3.63
Humpapvirus(Type 6,11,16,18,31,33,45,52,58) 4 Vaccines and antisera 6,024 0.00 0.00 0.00 3.61
Wool alcohols 41 Emollients 2,105 0.02 0.00 0.01 3.39

Prescribing where Croydon Gp Super Network PCN is lower than most

BNF Chemical Chemical Items BNF Subparagraph Subparagraph Items Ratio Mean std Z_Score Plots
Colecalciferol 13,800 Vitamin D 15,016 0.92 0.97 0.01 -3.28
Desogestrel 1,167 Oral progestogen-only contraceptives 1,362 0.86 0.94 0.03 -2.89
Chlorhexidine gluconate 94 Mouth-washes, gargles and dentifrices 110 0.85 0.98 0.05 -2.68
Methotrexate 997 Rheumatic disease suppressant drugs 2,914 0.34 0.58 0.11 -2.21
Losartan potassium 2,118 Angiotensin-II receptor antagonists 12,183 0.17 0.50 0.16 -2.10
Trimethoprim 486 Sulfonamides and trimethoprim 663 0.73 0.87 0.07 -2.06
Pizotifen malate 169 Prophylaxis of migraine 465 0.36 0.63 0.13 -2.04
Clotrimazole 404 Vaginal and vulval infections 502 0.80 0.90 0.05 -2.00
Water for injection 12 Electrolytes and water 23 0.52 0.82 0.16 -1.87
Lidocaine hydrochloride 152 Local anaesthetics 192 0.79 0.91 0.07 -1.73