Static outliers for Eastview 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 Eastview Surgery is higher than most

BNF Chemical	Chemical Items	BNF Subparagraph	Subparagraph Items	Ratio	Mean	std	Z_Score	Plots
Estradiol and nomegestrol☰	2	Combined hormonal contraceptives	92	0.02	0.00	0.00	8.97
Zoely 2.5mg/1.5mg tablets : 2
Azelastine hydrochloride☰	52	Drugs used in nasal allergy	461	0.11	0.01	0.01	8.70
Azelastine 140micrograms/dose nasal spray : 52
Irbesartan☰	904	Angiotensin-II receptor antagonists	1355	0.67	0.09	0.08	6.95
Irbesartan 75mg tablets : 162 Irbesartan 150mg tablets : 351 Irbesartan 300mg tablets : 391
Perindopril erbumine☰	1826	Angiotensin-converting enzyme inhibitors	2538	0.72	0.09	0.10	6.41
Perindopril erbumine 2mg tablets : 605 Perindopril erbumine 4mg tablets : 714 Perindopril erbumine 8mg tablets : 507
Ertugliflozin☰	16	Other antidiabetic drugs	746	0.02	0.00	0.00	6.23
Ertugliflozin 5mg tablets : 16

Prescribing where Eastview Surgery is lower than most

BNF Chemical	Chemical Items	BNF Subparagraph	Subparagraph Items	Ratio	Mean	std	Z_Score	Plots
Levothyroxine sodium☰	2429	Thyroid hormones	2469	0.98	1.00	0.00	-5.03
Levothyroxine sodium 25microgram tablets : 801 Levothyroxine sodium 50microgram tablets : 748 Levothyroxine sodium 75microgram tablets : 93 Levothyroxine sodium 100microgram tablets : 781 Levothyroxine sodium 12.5microgram tablets : 6
Doxazosin mesilate☰	607	Alpha-adrenoceptor blocking drugs	649	0.94	0.99	0.02	-2.80
Doxazosin 1mg tablets : 130 Doxazosin 2mg tablets : 200 Doxazosin 4mg tablets : 266 Doxazosin 4mg modified-release tablets : 6 Doxazosin 8mg tablets : 5
Ramipril☰	584	Angiotensin-converting enzyme inhibitors	2538	0.23	0.69	0.17	-2.76
Ramipril 1.25mg capsules : 99 Ramipril 2.5mg capsules : 188 Ramipril 5mg capsules : 145 Ramipril 10mg capsules : 73 Ramipril 1.25mg tablets : 47 Ramipril 5mg tablets : 9 Ramipril 2.5mg/5ml oral solution sugar free : 8 Ramipril 10mg tablets : 10 Ramipril 2.5mg tablets : 5
Mirtazapine☰	559	Other antidepressant drugs	1785	0.31	0.57	0.11	-2.40
Mirtazapine 30mg tablets : 88 Mirtazapine 15mg tablets : 195 Mirtazapine 45mg tablets : 257 Mirtazapine 45mg orodispersible tablets : 9 Mirtazapine 15mg orodispersible tablets : 10
Glycopyrronium bromide☰	0	Antimuscarinic drugs	7	0.00	0.82	0.36	-2.30