Static outliers for Lisson Grove Health Centre

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 Lisson Grove Health Centre is higher than most

BNF Chemical	Chemical Items	BNF Subparagraph	Subparagraph Items	Ratio	Mean	std	Z_Score
Prazosin hydrochloride	68	Alpha-adrenoceptor blocking drugs	247	0.28	0.00	0.01	22.26
Prazosin 500microgram tablets : 55 Prazosin 1mg tablets : 13
Isometheptene mucate	4	Non-opioid analgesics and compound preparations	1830	0.00	0.00	0.00	11.79
Paracetamol 325mg / Isometheptene 65mg capsules : 4
Tiaprofenic acid	3	Non-steroidal anti-inflammatory drugs	397	0.01	0.00	0.00	10.79
Tiaprofenic acid 300mg tablets : 3
Methadone hydrochloride	45	Opioid analgesics	1109	0.04	0.00	0.00	10.47
Methadone 5mg tablets : 45
Dexamfetamine sulfate	58	CNS Stimulants and drugs used for ADHD	97	0.60	0.03	0.07	8.66
Dexamfetamine 5mg tablets : 58

Prescribing where Lisson Grove Health Centre is lower than most

BNF Chemical	Chemical Items	BNF Subparagraph	Subparagraph Items	Ratio	Mean	std	Z_Score
Doxazosin mesilate	176	Alpha-adrenoceptor blocking drugs	247	0.71	0.99	0.02	-14.09
Doxazosin 4mg tablets : 95 Doxazosin 4mg modified-release tablets : 30 Doxazosin 8mg modified-release tablets : 1 Doxazosin 1mg tablets : 23 Doxazosin 2mg tablets : 27
Allopurinol	171	Gout and cytotoxic induced hyperiuicaemia	230	0.74	0.89	0.05	-2.83
Allopurinol 100mg tablets : 131 Allopurinol 300mg tablets : 40
Sildenafil (Erectile Dysfunction)	130	Drugs for erectile dysfunction	225	0.58	0.77	0.09	-2.02
Sildenafil 100mg tablets : 109 Sildenafil 50mg tablets : 18 Sildenafil 25mg tablets : 3
Tacrolimus	7	Drugs affecting the immune response	17	0.41	0.81	0.21	-1.91
Tacrolimus 0.1% ointment : 4 Tacrolimus 0.03% ointment : 3
Acamprosate calcium	9	Alcohol dependence	36	0.25	0.83	0.31	-1.89
Acamprosate 333mg gastro-resistant tablets : 9