Static outliers for Lakenham 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 Lakenham Surgery is higher than most

BNF Chemical	Chemical Items	BNF Subparagraph	Subparagraph Items	Ratio	Mean	std	Z_Score	Plots
Pericyazine☰	552	Antipsychotic drugs	2570	0.21	0.00	0.02	10.92
Pericyazine 2.5mg tablets : 438 Pericyazine 10mg tablets : 114
Valproic acid☰	61	Control of epilepsy	2998	0.02	0.00	0.00	10.80
Valproic acid 150mg gastro-resistant capsules : 22 Valproic acid 300mg gastro-resistant capsules : 22 Valproic acid 500mg gastro-resistant capsules : 17
Disopyramide phosphate☰	22	Drugs for arrhythmias	75	0.29	0.00	0.03	10.46
Disopyramide 250mg modified-release tablets : 22
Combined mestranol☰	1	Combined hormonal contraceptives	150	0.01	0.00	0.00	10.06
Mestranol 50microgram / Norethisterone 1mg tablets : 1
Nefopam hydrochloride☰	360	Non-opioid analgesics and compound preparations	2721	0.13	0.01	0.02	7.26
Nefopam 30mg tablets : 360

Prescribing where Lakenham Surgery is lower than most

BNF Chemical	Chemical Items	BNF Subparagraph	Subparagraph Items	Ratio	Mean	std	Z_Score	Plots
Ivermectin☰	1	Topical preparation for rosacea	9	0.11	0.88	0.24	-3.25
Ivermectin 10mg/g cream : 1
Ispaghula husk☰	41	Bulk-forming laxatives	56	0.73	0.96	0.07	-3.11
Fybogel 3.5g effervescent granules sachets plain SF : 1 Fybogel Hi-Fibre Orange 3.5g effervescent granules sachets : 1 Fybogel Lemon 3.5g effervescent granules sachets SF : 8 Ispaghula husk 3.5g efferv gran sach gluten free sugar free : 25 Fybogel Orange 3.5g effervescent granules sachets SF : 6
Hydralazine hydrochloride☰	0	Vasodilator antihypertensive drugs	5	0.00	0.85	0.28	-3.01
Codeine phosphate☰	0	Cough suppressants	3	0.00	0.76	0.35	-2.18
Atropine sulfate☰	0	Mydriatics and cycloplegics	1	0.00	0.72	0.38	-1.91