Static outliers for Tredegar 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 Tredegar Practice is higher than most

BNF Chemical	Chemical Items	BNF Subparagraph	Subparagraph Items	Ratio	Mean	std	Z_Score	Plots
Selegiline hydrochloride☰	18	Dopaminergic drugs used in parkinsonism	85	0.21	0.00	0.01	14.31
Selegiline 5mg tablets : 18
Other topical corticosteroid preparations☰	2	Topical corticosteroids	476	0.00	0.00	0.00	11.42
Propylene glycol 40% in Clobetasol 0.05% cream : 2
Darifenacin hydrobromide☰	86	Drugs for urinary frequency enuresis and incontinence	237	0.36	0.01	0.04	9.58
Darifenacin 7.5mg modified-release tablets : 62 Darifenacin 15mg modified-release tablets : 24
Hydrocort sodiumphos☰	8	Antibacterials	26	0.31	0.01	0.03	8.98
Hydrocortisone sodium phos 3.35mg/ml eye dps 0.4ml ud : 8
Methadone hydrochloride☰	33	Opioid analgesics	950	0.03	0.00	0.00	8.93
Methadone 5mg tablets : 12 Physeptone 5mg tablets : 21

Prescribing where Tredegar Practice is lower than most

BNF Chemical	Chemical Items	BNF Subparagraph	Subparagraph Items	Ratio	Mean	std	Z_Score	Plots
Trimethoprim☰	14	Sulfonamides and trimethoprim	44	0.32	0.86	0.13	-4.23
Trimethoprim 50mg/5ml oral suspension sugar free : 2 Trimethoprim 200mg tablets : 9 Trimethoprim 100mg tablets : 3
Aciclovir☰	60	Herpes simplex and varicella-zoster	88	0.68	0.95	0.07	-3.96
Aciclovir 400mg tablets : 35 Aciclovir 800mg dispersible tablets : 2 Aciclovir 200mg dispersible tablets : 2 Aciclovir 200mg tablets : 16 Aciclovir 800mg tablets : 5
Dexamethasone☰	22	Otitis externa	61	0.36	0.78	0.13	-3.19
Otomize ear spray : 22
Co-codamol (Codeine phosphate/paracetamol)☰	8	Non-opioid analgesics and compound preparations	1063	0.01	0.45	0.15	-2.88
Co-codamol 8mg/500mg tablets : 1 Co-codamol 30mg/500mg tablets : 1 Zapain 30mg/500mg tablets : 1 Co-codamol 15mg/500mg tablets : 5
Solifenacin☰	6	Drugs for urinary frequency enuresis and incontinence	237	0.03	0.33	0.12	-2.60
Solifenacin 5mg tablets : 6