Static outliers for Evenwood Medical 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. 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 Evenwood Medical Practice is higher than most

BNF Chemical	Chemical Items	BNF Subparagraph	Subparagraph Items	Ratio	Mean	std	Z_Score	Plots
Zuclopenthixol hydrochloride☰	20	Antipsychotic drugs	122	0.16	0.01	0.01	11.22
Zuclopenthixol 10mg tablets : 10 Zuclopenthixol 25mg tablets : 10
Loprazolam mesilate☰	6	Hypnotics	107	0.06	0.00	0.01	8.22
Loprazolam 1mg tablets : 6
Exemestane☰	24	Breast cancer	41	0.59	0.06	0.07	7.60
Exemestane 25mg tablets : 24
Co-dydramol (Dihydrocodeine/paracetamol)☰	117	Non-opioid analgesics and compound preparations	287	0.41	0.05	0.06	6.30
Co-dydramol 10mg/500mg tablets : 117
Trazodone hydrochloride☰	195	Tricyclic and related antidepressant drugs	455	0.43	0.06	0.06	6.27
Trazodone 50mg capsules : 89 Trazodone 100mg capsules : 63 Trazodone 150mg tablets : 30 Trazodone 100mg tablets : 9 Trazodone 50mg tablets : 4

Prescribing where Evenwood Medical Practice is lower than most

BNF Chemical	Chemical Items	BNF Subparagraph	Subparagraph Items	Ratio	Mean	std	Z_Score	Plots
Gliclazide☰	49	Sulfonylureas	152	0.32	0.92	0.14	-4.44
Gliclazide 40mg tablets : 17 Gliclazide 80mg tablets : 21 Gliclazide 30mg modified-release tablets : 11
Amitriptyline hydrochloride☰	238	Tricyclic and related antidepressant drugs	455	0.52	0.84	0.08	-4.15
Amitriptyline 10mg tablets : 136 Amitriptyline 25mg tablets : 74 Amitriptyline 50mg tablets : 28
Nitrofurantoin☰	82	Urinary-tract infections	110	0.75	0.97	0.06	-3.63
Nitrofurantoin 50mg capsules : 54 Nitrofurantoin 50mg tablets : 2 Nitrofurantoin 100mg tablets : 6 Nitrofurantoin 100mg modified-release capsules : 20
Glucose☰	0	Treatment of hypoglycaemia	2	0.00	0.75	0.21	-3.62
Senna☰	8	Stimulant laxatives	61	0.13	0.55	0.14	-3.03
Senna 7.5mg tablets : 8