Static outliers for Clarkson 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 Clarkson Surgery is higher than most

BNF Chemical	Chemical Items	BNF Subparagraph	Subparagraph Items	Ratio	Mean	std	Z_Score	Plots
Ketoprofen☰	312	Rubefacients, topical NSAIDS, capsaicin and poultice	721	0.43	0.02	0.06	6.81
Ketoprofen 2.5% gel : 312
Liquid paraffin☰	7	Emollient bath and shower preparations	18	0.39	0.03	0.07	4.99
Doublebase emollient bath additive : 1 Emulsiderm emollient : 6
Bisacodyl☰	370	Stimulant laxatives	601	0.62	0.14	0.10	4.82
Bisacodyl 5mg gastro-resistant tablets : 368 Bisacodyl 10mg suppositories : 2
Metoprolol tartrate☰	269	Beta-adrenoceptor blocking drugs	5436	0.05	0.01	0.01	4.54
Metoprolol 50mg tablets : 252 Metoprolol 100mg tablets : 17
Phenoxybenzamine hydrochloride☰	6	Alpha-adrenoceptor blocking drugs	1584	0.00	0.00	0.00	3.95
Phenoxybenzamine 10mg capsules : 6

Prescribing where Clarkson Surgery is lower than most

BNF Chemical	Chemical Items	BNF Subparagraph	Subparagraph Items	Ratio	Mean	std	Z_Score	Plots
Gliclazide☰	599	Sulfonylureas	1441	0.42	0.92	0.14	-3.75
Gliclazide 80mg tablets : 416 Gliclazide 40mg tablets : 172 Gliclazide 60mg modified-release tablets : 6 Gliclazide 30mg modified-release tablets : 5
Senna☰	100	Stimulant laxatives	601	0.17	0.55	0.14	-2.77
Senna 7.5mg tablets : 87 Senna 7.5mg/5ml oral solution sugar free : 8 Senna 15mg tablets : 5
Quinine sulfate☰	197	Antimalarials	322	0.61	0.89	0.14	-1.99
Quinine sulfate 200mg tablets : 128 Quinine sulfate 300mg tablets : 69
Atropine sulfate☰	0	Mydriatics and cycloplegics	6	0.00	0.72	0.38	-1.91
Mercaptopurine☰	9	Antimetabolites	53	0.17	0.80	0.35	-1.82
Mercaptopurine 50mg tablets : 9