Static outliers for Royal Primary Care South

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 Royal Primary Care South is higher than most

BNF Chemical	Chemical Items	BNF Subparagraph	Subparagraph Items	Ratio	Mean	std	Z_Score	Plots
Gluten free/low protein drink☰	2	Foods for special diets	150	0.01	0.00	0.00	9.24
Mevalia Lattis low protein drink : 2
Cefradine☰	12	Cephalosporins	19	0.63	0.02	0.08	8.03
Cefradine 500mg capsules : 1 Cefradine 250mg capsules : 11
Trifluoperazine☰	64	Antipsychotic drugs	1220	0.05	0.00	0.01	6.37
Trifluoperazine 5mg/5ml oral solution sugar free : 22 Trifluoperazine 1mg tablets : 21 Trifluoperazine 5mg tablets : 21
Chlohexidine gluconate (Emollient)☰	2	Emollients	310	0.01	0.00	0.00	3.46
Eczmol 1% cream : 2
Dexpanthenol☰	7	Emollients	310	0.02	0.00	0.01	3.37
Bepanthen Nappy Care 5% ointment : 7

Prescribing where Royal Primary Care South is lower than most

BNF Chemical	Chemical Items	BNF Subparagraph	Subparagraph Items	Ratio	Mean	std	Z_Score	Plots
Cefalexin☰	7	Cephalosporins	19	0.37	0.96	0.10	-5.78
Cefalexin 250mg/5ml oral suspension : 1 Cefalexin 500mg capsules : 6
Indapamide☰	105	Thiazides and related diuretics	1254	0.08	0.42	0.16	-2.13
Indapamide 2.5mg tablets : 78 Indapamide 1.5mg modified-release tablets : 27
Amitriptyline hydrochloride☰	2116	Tricyclic and related antidepressant drugs	3096	0.68	0.84	0.08	-2.05
Amitriptyline 10mg tablets : 1455 Amitriptyline 25mg tablets : 404 Amitriptyline 50mg tablets : 256 Amitriptyline 50mg/5ml oral solution sugar free : 1
Midazolam hydrochloride☰	2	Drugs used in status epilepticus	11	0.18	0.79	0.30	-2.02
Midazolam 10mg/2ml oromucosal soln pf oral syringes SF : 1 Buccolam 10mg/2ml oromucosal soln pre-filled oral syringes : 1
Hydralazine hydrochloride☰	20	Vasodilator antihypertensive drugs	69	0.29	0.85	0.28	-1.99
Hydralazine 50mg tablets : 13 Hydralazine 25mg tablets : 7