Static outliers for Northgate Village 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 Northgate Village Surgery is higher than most

BNF Chemical	Chemical Items	BNF Subparagraph	Subparagraph Items	Ratio	Mean	std	Z_Score
Low protein miscellaneous	4	Foods for special diets	108	0.04	0.00	0.00	18.84
Taranis low protein hazelnut spread : 4
Salicylic acid	1	Drugs for oral ulceration and inflammation	28	0.04	0.00	0.00	16.32
Salicylic acid 1% / Rhubarb extract 5% oromucosal solution : 1
Rufinamide	12	Control of epilepsy	1082	0.01	0.00	0.00	6.80
Rufinamide 200mg tablets : 6 Rufinamide 400mg tablets : 6
Gluten free/low protein bread	16	Foods for special diets	108	0.15	0.01	0.02	6.76
Mevalia low protein ciabattine : 1 Mevalia low protein mini baguette : 3 Mevalia low protein pizza base : 7 Mevalia low protein pan carre : 5
Varicella vaccine live	2	Vaccines and antisera	8	0.25	0.00	0.04	5.55
Varivax vacc inj 0.5ml vials : 2

Prescribing where Northgate Village Surgery is lower than most

BNF Chemical	Chemical Items	BNF Subparagraph	Subparagraph Items	Ratio	Mean	std	Z_Score
Quinine sulfate	28	Antimalarials	58	0.48	0.89	0.14	-2.90
Quinine sulfate 300mg tablets : 8 Quinine sulfate 200mg tablets : 20
Loperamide hydrochloride	64	Antimotility drugs	66	0.97	1.00	0.01	-2.38
Loperamide 2mg capsules : 58 Loperamide 1mg/5ml oral solution sugar free : 6
Budesonide	0	Corticosteroids	2	0.00	0.70	0.34	-2.08

Losartan potassium	109	Angiotensin-II receptor antagonists	671	0.16	0.50	0.19	-1.81
Losartan 100mg tablets : 63 Losartan 25mg tablets : 22 Losartan 50mg tablets : 24
Sodium chloride	0	Topical nasal decongestants	5	0.00	0.54	0.31	-1.72