Static outliers for The Churchfield Road 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 The Churchfield Road Surgery is higher than most

BNF Chemical	Chemical Items	BNF Subparagraph	Subparagraph Items	Ratio	Mean	std	Z_Score	Plots
Iron and folic acid☰	18	Oral iron	88	0.20	0.00	0.01	33.18
Pregaday 322mg/350microgram tablets : 1 Ferrous sulfate 325mg / Folic acid 350microgram MR tab : 12 Ferrous fumarate 322mg / Folic acid 350microgram tablets : 5
Promethazine teoclate☰	26	Drugs used in nausea and vertigo	102	0.25	0.00	0.01	17.24
Promethazine teoclate 25mg tablets : 26
Imipramine hydrochloride☰	21	Tricyclic and related antidepressant drugs	124	0.17	0.01	0.01	15.61
Imipramine 25mg tablets : 21
Sacubitril/valsartan☰	67	Angiotensin-II receptor antagonists	241	0.28	0.02	0.02	12.70
Entresto 49mg/51mg tablets : 36 Entresto 97mg/103mg tablets : 2 Entresto 24mg/26mg tablets : 2 Sacubitril 49mg / Valsartan 51mg tablets : 17 Sacubitril 24mg / Valsartan 26mg tablets : 10
Enalapril maleate☰	136	Angiotensin-converting enzyme inhibitors	405	0.34	0.03	0.03	8.81
Enalapril 10mg tablets : 48 Enalapril 20mg tablets : 51 Enalapril 2.5mg tablets : 12 Enalapril 5mg tablets : 25

Prescribing where The Churchfield Road Surgery is lower than most

BNF Chemical	Chemical Items	BNF Subparagraph	Subparagraph Items	Ratio	Mean	std	Z_Score	Plots
Desogestrel☰	13	Oral progestogen-only contraceptives	18	0.72	0.94	0.05	-3.98
Cerazette 75microgram tablets : 1 Desogestrel 75microgram tablets : 12
Methylphenidate hydrochloride☰	0	CNS Stimulants and drugs used for ADHD	11	0.00	0.65	0.21	-3.15
Carbimazole☰	5	Antithyroid drugs	8	0.62	0.93	0.11	-2.89
Carbimazole 5mg tablets : 5
Other emollient preparations☰	35	Emollients	50	0.70	0.89	0.07	-2.70
E45 cream : 2 Aveeno cream : 1 Doublebase gel : 1 Doublebase emollient shower gel : 1 Doublebase emollient wash gel : 1 Dermol 500 lotion : 23 White soft paraffin 50% / Liquid paraffin 50% ointment : 3 Diprobase ointment : 3
Lamotrigine☰	0	Control of epilepsy	347	0.00	0.11	0.04	-2.65